Abstract
Sleep deprivation has far-reaching consequences on the brain and behavior, impacting memory, attention, and metabolism. Previous research has focused on gene expression changes in individual brain regions, such as the hippocampus or cortex. Therefore, it is unclear how uniformly or heterogeneously sleep loss affects the brain. Here, we use spatial transcriptomics to define the impact of a brief period of sleep deprivation across the brain in male mice. We find that sleep deprivation induced pronounced differences in gene expression across the brain, with the greatest changes in the hippocampus, neocortex, hypothalamus, and thalamus. Both the differentially expressed genes and the direction of regulation differed markedly across regions. Importantly, we developed bioinformatic tools to register tissue sections and gene expression data into a common anatomical space, allowing a brain-wide comparison of gene expression patterns between samples. Our results suggest that distinct molecular mechanisms acting in discrete brain regions underlie the biological effects of sleep deprivation.
Subject terms: Sleep deprivation, Neuroscience
Sleep deprivation impacts molecular changes across brain regions. Here, the authors utilize a spatial. transcriptomics approach to elucidate acute sleep deprivation-induced gene expression signature. across regions and subregions of the brain.
Introduction
Sleep deprivation is a growing problem that affects more than one-third of adults in the U.S. and more than 70% of teenagers and adolescents1. Loss of sleep impacts cognition, attention, and metabolism2–5. These processes are mediated by distinct neural circuits in specific brain regions—the hippocampus, the cortex, and hypothalamus, respectively. Sleep and circadian rhythm disorders have also been linked to the increased incidence and accelerated progression of neurodegenerative diseases, including Alzheimer’s disease6–10. Given the serious consequences of sleep loss for individuals and the interaction of sleep deprivation with many diseases, it is important to understand the cellular and molecular consequences of sleep deprivation. To this end, we have used non-biased spatial transcriptomics to define whether sleep loss has distinct molecular impacts on specific brain regions.
Sleep deprivation impacts protein synthesis and gene regulation through many mechanisms including alterations to epigenetic regulation, transcription, and mRNA processing11–19. Estimates suggest that up to 10% of cortical transcripts are regulated with sleep/wake cycles, particularly by the length of time awake20–22. In the hippocampus, prolonged wakefulness causes changes in the expression of genes associated with RNA splicing, cell adhesion, dendritic localization, the synapse, and the postsynaptic membrane11,13,23,24. However, the brain is highly heterogeneous and subserves many different functions; as brain regions and circuits differ in their roles, they may differ dramatically in their response to sleep loss, and observations from one brain region may not be generalized to the whole brain.
Recent technological advances in genome-wide spatial transcriptomics offer enormous potential for providing detailed molecular maps that overcome limitations associated with single cell or single nuclear RNA sequencing (sc/snRNA-seq) and microscopy-based spatial transcriptomics methods25. This approach has been successfully used to generate detailed datasets and cell-type specific gene expression signatures26–29, but it has not yet been used to profile changes in gene expression across multiple brain regions after experience. A further challenge for data analysis is that a significant hurdle remains in terms of finding a strategy to align the brain regions across slices from multiple subjects or from independent experiments for data integration in multi-sample analyses. To investigate gene expression changes within the adult mouse brain after sleep deprivation, we used the 10x Genomics Visium platform, a barcoding-based, transcriptome-wide approach that generates spatial maps of gene expression. We collected gene expression data from each major brain region across a coronal brain slice, enabling us to profile multiple brain regions simultaneously. Using this technique, we were also able to get detailed, subregion and layer specific gene expression changes within the hippocampus and cortex. Finally, we present an alternative to a region-of-interest type of analysis by registering multiple slices into a common space using the Common Coordinate Framework (CCF) from the Allen Brain Atlas30, thus adjusting for differences in the alignment of brain tissue sections and allowing for a comparison between samples. These data and analytical approaches provide a scientific resource for the neuroscientific community, and they demonstrate the diverse impact of sleep loss on gene expression across the brain.
Results
Using spatial transcriptomics, we profiled spatial gene expression in coronal brain slices from sleep-deprived (SD) or control (non-sleep deprived (NSD)) adult male mice. Each coronal section covered between 1736 and 3103 spots on the Visium slides (Supplementary Data 1). We sequenced each sample to a median depth of 2.26E + 08 (interquartile range 2.10E + 08–2.37E + 08), which corresponded to a mean of 93245 reads and a mean of 5978 genes per spot (Supplementary Data 1). Importantly, we were able to detect over 21,000 genes for each sample (Supplementary Data 1). However, the individual number of genes detected in each spot is three to four times lower than the total number of expressed genes detected due to cell-type and brain-region specific differences in gene expression (Supplementary Fig. 1). We note that these rates are analogous to snRNA-seq and scRNA-seq data using the 10x Genomics Chromium platform, where a “cell” barcode on the Chromium platform corresponds to a “spatial” barcode on the Visium platform. However, unlike snRNA-seq data, which contains high numbers of intronic reads that map to immature transcripts, we found strong enrichment of mature messenger RNAs with high mean rates of exonic alignments (mean: 88.3%; IQR: 87.7–89.4%) (Supplementary Data 1).
We first generated region-enriched expression profiles for the samples from each condition (Fig. 1A–C and Supplementary Fig. 2). As expected, this approach predicted brain regions with high reliability (Fig. 1B) and recapitulated the brain regions from the reference coronal mouse Allen brain atlas31 (Fig. 1C). Each brain region was characterized by specific transcriptional signatures and unsupervised clustering of these region expression profiles revealed distinct clusters (Fig. 1D) and top biomarkers (Fig. 1E). Supplementary Table 2 reports the expression levels for all genes with no filters. Due to the transcriptional similarity of the basomedial and basolateral amygdalar subnuclei with the subnuclei of the amygdalar medial area, and the spatial proximity and similarity with the allocortex, UMAP clustering reports the striatum-like amygdalar nuclei and the allocortex as repeated clusters with slightly different transcriptional signatures depending upon the grouping of the basomedial and basolateral subnuclei (Fig. 1D). We merged anatomically adjacent spots from the two clusters to generate the labeled brain regions. Together, these results highlight the ability of spatial transcriptomics to achieve high-resolution expression profiling across the mouse brain.
Sleep deprivation exerts differential effects on transcriptional activity in each brain region
Sleep deprivation affects different brain functions ranging from cognition and affective processing that each rely upon distinct neuronal circuits17,22–24,32–35. However, little is known about how sleep deprivation alters transcriptomic activity in individual brain regions, as bulk sequencing approaches inevitably average out regionalized effects. To address this problem, we performed differential gene expression analysis in each of the brain regions identified in the coronal sections (Fig. 1). In the analysis, significant differentially expressed genes (DEGs) were identified using two filters, an FDR of 0.001 and an absolute fold change threshold of 1.2. Significant DEGs for each brain region are reported in Supplementary Table 3. After filtering, we found that the hippocampal region had the greatest number of significant DEGs affected by sleep loss (592 DEGs), followed by the neocortex (401 DEGs), the hypothalamus (266 DEGs), and the thalamus (113 DEGs) (Fig. 2A). Some of these DEGs, such as Rbm3, Hspa5, and Srsf5, have been previously shown to be affected after sleep deprivation in our previous studies of the hippocampus11,36,37 and in studies of other brain regions13–15,17,21,34,38,39.
The molecular functions of the DEGs showed region-specific differences (Fig. 2B–E and Supplementary Data 4). For the hippocampal region, many molecular functions related to RNA processing were enriched (Fig. 2B). For the neocortex, molecular functions related to protein kinase activity, GTPase activity, ubiquitin ligase activity, and DNA-binding transcription factor binding were enriched (Fig. 2C). The DEGs in the hypothalamus were enriched for molecular functions related to neuropeptide and hormone activity, as well as glutathione transferase and peroxidase activity (Fig. 2D). Finally, the DEGs in the thalamus were enriched for the Myogenic Regulatory Factor (MRF) binding molecular function (Fig. 2E). Surprisingly, ~98% of the DEGs in the hippocampal region were significantly downregulated whereas ~96% of the DEGs in the neocortex were significantly upregulated (Fig. 2B, C and Supplementary Fig. 3).
We next investigated how many of those total DEGs are uniquely affected in each brain region by analyzing the degree of overlap between the DEGs in the brain regions that had at least 50 DEGs affected by sleep deprivation (Fig. 2F). Although there were many connections between different brain regions, the majority (50–83%) of the DEGs were specifically affected in their respective brain region. Of the 592 DEGs found in the hippocampal region, 489 were exclusively affected in the hippocampal region (489/592 DEGs), 306/401 in the neocortex, 199/266 in the hypothalamus, 56/113 in the thalamus, and 33/66 in the striatum-like amygdalar nuclei (Supplementary Data 3). Interestingly, only 35 DEGs were found to be in common between the neocortex and the allocortex, resulting in one significantly enriched pathway: protein kinase inhibitor activity (Supplementary Fig. 4). All other sets of common DEGs (Supplementary Data 5) were too few in number to reveal enriched molecular functions.
Hippocampal subregions are differentially impacted by sleep deprivation
As our results here and previous studies have demonstrated, the hippocampus is highly susceptible to the effects of acute sleep deprivation11,13,24,36,37. This brain region is comprised of several substructures—CA1, CA2, CA3, and the dentate gyrus (DG)—each with different functions in learning and memory40–45. We performed a deconvolution of the CA1 pyramidal layer and the dentate gyrus (DG) granule cell layer using a reference scRNA-seq whole hippocampus mouse dataset from the Allen Brain Atlas46 (Fig. 3A) and were able to distinguish the areas CA2 and CA3 pyramidal layers based on spatial topography. Similarly, because the dendritic layers of CA1 are known to undergo structural changes following sleep deprivation47–49, we also used spatial topography to define and include the stratum radiatum and oriens layers of CA1 in our analysis (Fig. 3B). Differential gene expression analysis in each hippocampal subregion revealed unique gene expression changes and molecular functions enriched that were specific to a subregion (Fig. 3C, Supplementary Data 6 and 7). Of the DEGs identified in each region, 51/62 DEGs were uniquely affected in CA1, 34/41 in DG, 53/61 in stratum radiatum, and 4/4 in stratum oriens. The CA1 pyramidal layer and stratum radiatum were most impacted by sleep deprivation, with the most DEGs and unique DEGs of the areas examined. Stratum radiatum had 53 unique DEGs enough to enrich the cyclin-dependent protein serine/threonine kinase activity, as well as the pyramidal CA1 cells with their 51 unique DEGs that enriched the glutamate receptor binding. Interestingly, there were no genes significantly affected in the combined CA2 and CA3 pyramidal layers after sleep deprivation. This finding supports other observations that CA1 and the DG are impacted by sleep deprivation while area CA3 is less affected37,49.
Sleep deprivation causes layer-specific transcriptional changes in the cortex
The neocortex was the second-most impacted by sleep deprivation (Fig. 2A). The cortex comprises of different layers that each are involved in various functions of receiving, integrating, and outputting information50. To understand how sleep deprivation differently impacts the layers of the cortex, we examined the gene expression profiles within each cortical layer. We performed a deconvolution of the spatial datasets by integrating them with a reference scRNA-seq dataset of ~14,000 adult mouse cortical cell taxonomy from the Allen Institute51. This allowed us to identify the layers of the neocortex based on the prediction score in each spot (Fig. 4A) and perform differential gene expression analyses in each layer (Supplementary Data 8 and Supplementary Fig. 5). Layers 2/3 and 5 are the most transcriptionally affected after sleep deprivation with 222 and 225 significant DEGs, respectively (Supplementary Data 9). Differential gene expression analysis in each cortical layer revealed distinct gene expression changes and molecular functions that were uniquely enriched in certain layers (Fig. 4B), which may relate to the differential function of these layers in intracortical processing and cortical output. Layer 5, which contains neurons that are the main output of the cortex, had 174 unique DEGs that included molecular functions related to sterol binding, cyclic adenosine monophosphate (cAMP) binding, structural constituents of the postsynapse, and ion channel regulator activity. Layer 2/3, which functions largely in information processing within the cortex, had 149 unique DEGs that included molecular functions related to phosphatase inhibitor activity, adenylate cyclase inhibiting G protein-coupled glutamate receptor activity, and ionotropic glutamate receptor binding.
Registration of slices to a common anatomical reference space via the Spatial Transcriptomics Analysis Tool (STAnly) allows the unrestricted analysis of transcriptomic data across entire brain slices
Our deconvolution approach (used in Figs. 1–4) subdivides a given brain slice into different larger brain regions based on their transcriptomic activity. Although this is a powerful tool to analyze spatial gene expression changes, it inevitably comes at the price of a loss of spatial resolution, as this approach necessarily pools over larger brain regions, and requires a prior biological knowledge of cell type-specific gene expression profiles. To address this loss of spatial resolution, we established an analysis tool (Spatial Transcriptomics ANaLYsis (STANLY) that aligns dots from multiple samples from different animals into one common anatomical reference space, the Common Coordinate Framework (CCF) of the Allen Mouse Brain Atlas31, thus allowing a dot-by-dot comparison of the transcriptome in an unrestricted inference space (Fig. 5A). To account for different numbers of spots across slices, we generated “digital spots” in this same coordinate system to allow a statistical comparison across. Using this method, we detected at least 18,893 genes in all sample slices for changes in expression between NSD and SD. Of these, 413 genes (Supplementary Data 10) were significantly differentially expressed, with 150 genes showing an upregulation in all significant spots, 22 showing downregulation in all significant spots, and 256 showing a combination of up and down regulation across the sample space. These DEGs include previously described upregulated genes like Per1 (Fig. 5B), Nr4a1 (Fig. 5C), Homer1 (Fig. 5D), and Arc (Fig. 5E), which showed localized increases in the neocortex, as well as downregulated genes like Rbm3 (Fig. 5F) and Cirbp (Fig. 5G), which showed hippocampus-specific changes, similar to those seen in our deconvolution approach. Using ToppGene52, we found the top five enriched mouse phenotypes were related to abnormal synaptic transmission (83 DEGs), abnormal synaptic physiology (83 DEGs), abnormal learning/memory/conditioning (84 DEGs), abnormal cognition (84 DEGs), and abnormal CNS synaptic transmission (75 DEGs) across the whole coronal slice. GO-molecular function (GO:MF) enrichment analysis showed similar functions enriched in previously identified brain region such as RNA binding (found in the hippocampus), Ubiquitin-like protein ligase activity, GTP binding, kinase activity (found in the neocortex), and neuropeptide and hormone activity (found in the hypothalamus) (Supplementary Fig. 6 and Fig. 3).
We wanted to test the power of STANLY and spatial transcriptomics for subregional analysis within the hippocampus, particularly area CA1 and the dentate gyrus. Both area CA1 and the dentate gyrus were treated as binary masks, with dots situated within these regions included into our analyses. We then conducted a two-sample t-test at each spot within these masks as shown in Supplementary Fig. 7. Because we were only investigating one gene, Arc, we performed our p-value correction using the number of spots being tested, which was 140, giving us a threshold of p < 0.00075. Using this p-value, we found that sleep deprivation significantly increased the mRNA expression of the activity-dependent immediate early gene Arc in area CA1 (p < 0.0005), whereas there was little change or even slightly decreased expression of Arc in the dentate gyrus. To validate the reliability of our STANLY analyses, using samples from independent sleep deprivation experiments, we performed in situ hybridization using RNAscope (ACD) for Arc expression in the hippocampus. The RNAscope analysis revealed that acute sleep deprivation significantly increased Arc mRNA positive cells in the CA1, while there was no change in the DG (Supplementary Fig. 7). Arc shows increased expression in the hippocampus following acute sleep deprivation11,13. Moreover, Arc has also been identified as having differential expression in the subregions of the hippocampus after sleep deprivation with significantly increased levels of Arc in the CA1 and no change or decreased expression in the dentate gyrus53. Thus, the results from STANLY analysis comparing subregions within the hippocampus are consistent with our in situ hybridization experiments and with previously published results. These results validate the power of STANLY and spatial transcriptomic approaches to identify spatially restricted changes in gene expression.
Discussion
The identification of cell-type specific transcriptomic signatures has been invaluable in distinguishing subclasses of cell types in the brain54 and has provided insights into brain disorders such as epilepsy, autism, and Alzheimer’s disease55–57. However, the lack of spatial information associated with single cell transcriptomics represents a significant obstacle58,59, especially in an organ as complex as the brain. Spatial transcriptomics combines a spatial barcode of RNA transcripts with near single cell sequencing resolution providing a major advance for understanding gene regulation across brain regions. However, the recent development of this technology means that it is largely untested for the analysis of differential gene expression. Here, we used this technique to examine the important problem of how acute sleep deprivation affects gene expression across brain regions. The effects of sleep deprivation on public health, and as a risk factor increasing the susceptibility and incidence of numerous diseases, necessitate that we utilize and develop techniques that will provide more detailed understanding of the consequences of sleep loss.
The spatial transcriptomic platform provided sequencing depth comparable to single cell and single nuclear transcriptomic studies in terms of gene number per spot, with the advantage of enriching mature RNA transcripts (Supplementary Data 1). Potentially, the clustering of a small number of cells in the spots of the slides allows for a greater sequencing of mature cytoplasmic RNA molecules, compared to the nuclear mRNA that contains immature RNAs still being processed. This technique allowed us to anatomically distinguish individual brain regions by aligning brain regions with the reference mouse Allen brain atlas, where we found that individual brain regions showed distinct transcriptional profiles after acute sleep deprivation. Individual cell types clustered within a brain region similar to single cell transcriptomic studies (Fig. 1). Thus, these results demonstrate the comparability of spatial transcriptomics to the resolution of single-cell approaches with the added power of simultaneous brain-wide investigation and additional spatial information.
Given the recent development of the spatial transcriptomics platform, we employed both a relatively large number of samples for a transcriptomics study and a highly conservative statistical analysis using an FDR of 0.001 to determine differential gene expression in individual brain regions following acute sleep deprivation. Using a conservative FDR-corrected p < 0.001 as the threshold, we identified fewer differentially expressed genes in the hippocampus and the cortex compared to other transcriptomic studies11,13,21. As our sleep deprivation method and protocols were similar to other studies11,13, we believe that differences arise from our use of a highly conservative statistical approach to avoid false positives due to the large sample size (i.e., the number of spots in each slice). However, we recognize that our conservative approach may also result in false negatives, so all gene expression data is included in the Supplementary Tables and available through GEO (GSE222410). Importantly, all samples were collected at the same time of day as the circadian clock has independent effects on transcription60,61. In the current study, we were unable to investigate potential asymmetries in the response of the left and right hemisphere to the impacts of acute sleep deprivation, as we were limited by the size of the spatial transcriptomic slides in which only one hemisphere can fit within the bounds of the slide. In future studies, we plan to use spatial transcriptomics to investigate more nuanced impacts of sleep deprivation, such as interhemispheric differences.
We found that acute sleep deprivation had the greatest impact on gene regulation in the hippocampus, neocortex, hypothalamus and thalamus (Fig. 2A). Interestingly, this conservative approach strongly illustrated heterogeneity of brain regions in response to sleep deprivation, as we found little overlap in the differentially expressed genes across brain regions (Fig. 2F). Moreover, our results conclusively demonstrate that directional changes in gene expression following acute sleep deprivation vary widely across brain regions; approximately 98% of the differentially expressed genes downregulated in the hippocampus, while the opposite was true in the neocortex, which had approximately 96% of the differentially expressed genes upregulated (Fig. 2B, C). Thus, analysis of gene expression changes after acute sleep deprivation in older studies, in which the entire forebrain was collected, may have masked the nuanced effects of sleep deprivation on gene regulation. The dramatic differences in gene expression across brain regions in response to sleep deprivation also suggests that a single theory to explain the impact of wakefulness on the brain or the function of sleep is unlikely to be satisfactory.
The work presented here establishes the robustness and fidelity of spatial transcriptomics for the determination and analysis of differential gene expression within brain subregions as well as for comparisons of gene expression across the brain. For example, in the hippocampus, we found that acute sleep deprivation significantly reduced gene expression involved in RNA processing similar to what was found in previous research11. In the neocortex, upregulation was observed for genes involved in DNA binding and transcription factor activity, protein kinase regulation, GTPase regulation and ubiquitin like protein ligase activity. This upregulation of genes involved in DNA binding and transcription factor activity, such as the transcription factor Nr4a1, may explain the greater percentage of upregulated genes found in the neocortex as increased expression of NR4A1 would lead to increased expression of its target genes. Although a smaller number of genes were identified in the hypothalamus and thalamus, they nonetheless indicate significant changes in molecular function17. For instance, we found that the most significant alterations in the hypothalamus were for genes associated with neuropeptide and hormone signaling. The differences in the functions and molecular pathways affected in each region may provide key insights into how each structure is related to some of the broader and longer lasting effects of acute sleep deprivation. Importantly, the differentially expressed gene functions we identified in each brain region are consistent with the behavioral effects that have been observed following sleep deprivation and attributed to changes in neuronal function, such as changes in circadian behavior or impairments in long-term memory.
The high density of individually coded spots on the slide grid enabled sub-regional analysis of gene expression between slices from sleep deprived and non-sleep deprived mice when combined with a deconvolution approach using single cell reference data sets from the Allen Brain Atlas for the hippocampus (Fig. 3A) and the cortex (Fig. 4A). Subregional analysis of the hippocampus was done for the CA1, CA2/3 pyramidal cell layers, dentate gyrus granule cell layer, and the stratum oriens and the stratum radiatum which contain diverse populations of interneurons. Although both the stratum oriens and the stratum radiatum contain interneurons, the functions of these two layers are distinct, and receive different anatomical inputs. Given the disparate functions and circuitry of the hippocampal subregions, we predicted that sleep deprivation would result in distinct transcriptional profiles in these subregions. With the decreased number of sample spots in the analysis of hippocampal subregions, the FDR threshold was lowered to 0.1 for the identification of significant DEGs to reduce the number of false negatives, similar to the FDR used for RNA-seq studies of hippocampal subregions62. We found that sleep deprivation induced the largest number of changes in gene expression in the CA1 and stratum radiatum. Surprisingly, there were only four genes affected by sleep deprivation in the stratum oriens, although interneurons within this region have been shown to be plastic and provide input to CA1 pyramidal cells63. These results suggest that sleep deprivation has the broadest impact on gene regulation in the excitatory neurons of the hippocampus. This result is consistent with previous research in which manipulations of protein synthesis within hippocampal excitatory neurons ameliorated the impacts of sleep deprivation on hippocampus dependent long-term spatial memory64. However, it should be noted that the power of subregional analysis for differential gene expression within the hippocampus may be limited by the number of spots in each subregion. In comparison to the individual layered analysis of the neocortex, there were fewer differentially expressed genes detected in the subregions of the hippocampus (Fig. 3C vs 4B). It is probable that the small number of sample spots and subsequent lack of statistical power for analysis of the CA2 and CA3 subregions resulted in a failure to detect DEGs with some genes reported as false negatives. Future research in which single-cell RNA-seq is combined with spatial transcriptomics could resolve these issues.
We found that within the neocortex, sleep deprivation differentially affected individual cortical layers (Fig. 4B), and that Layers 2/3 and 5 were the most affected by sleep deprivation. Interestingly, changes in gene expression following sleep deprivation were unique for individual layers: more than 65% of the genes were unique in Layer 5 and 75% of the genes in Layer 2/3 were unique. Although the number of genes affected was smaller for Layer 4 and Layer 6, the number of layer specific gene changes for these layers was still approximately 50%. From this we can observe that there are distinct impacts of sleep deprivation on individual cortical layers. Indeed, Layer 2/3 function as corticocortical projections to layer 5 and form a prominent interlaminar pathway to amplify, integrate, distribute and temporarily store information within subsets of neurons65. From the Layer 5, pyramidal tract neurons project to multiple targets including ipsilateral striatum, thalamus, subthalamic nucleus and many brainstem and spinal cord regions66. The elevated level of response from these two layers highlight how the cortex is adapting in response to sleep deprivation, and these connections may better illustrate why cortical functions and properties are so altered by sleep loss67.
Spatial transcriptomics provides a potentially powerful approach for large scale comparisons of gene expression across multiple conditions or disease states. For the full capability of spatial transcriptomics to be realized, it is necessary to develop the analysis tools for the alignment of spatial transcriptomic data sets into a common anatomical reference space to allow an unrestricted comparison of gene expression between samples. To further this goal, we pioneered the adaption of bioinformatic tools to facilitate the transformation and registration of spatial transcriptomic data sets with the anatomical reference space of the Allen Mouse Brain Atlas (Fig. 5). By computationally aligning the spatial transcriptomic data through a digital spot workflow with the Common Coordinate Framework, we can observe gene expression changes between the sleep deprived and non-sleep deprived conditions for individual genes of interest. This coordinate approach allows significant changes in gene expression to be visualized and analyzed for individual spots across the brain (Fig. 5 and Supplementary Data 10) in greater detail and with much higher sensitivity for localized changes within larger anatomical structures than the region of interest approach above. We used this approach at its most basic level to examine single gene expression across the brain, finding 413 genes that significantly changed after sleep deprivation. However, our data shows that even genes with robust changes after sleep deprivation display regional differences in expression, which emphasizes that sleep deprivation has localized impacts on gene regulation. With the formidable technological advances that have been made over the past decade, specifically those enabling detailed analysis of gene regulation at multiple levels, one of the greatest challenges facing neuroscientists is the integration and management of complex multimodal data sets. There is a critical need to integrate large data sets for spatial and specific cell type characterization of the mouse brain, as the majority of preclinical research is done using the mouse model. The bioinformatic approach for spatial gene expression analysis across brain regions that we developed for this study helps to meet the challenge of integrating complex data sets for mouse spatial transcriptomic data sets and reveals critical regional selectivity in the impact of brief periods of sleep loss across the brain.
Methods
Animals
Male C57BL/6 J mice (Jackson Laboratory #000664), age 2.5–3.5 months were used for all the experiments. Mice were group housed (up to 5 per cage) in cages containing soft bedding with food (NIH-31 irradiated modified mouse diet #7913) and water available ad libitum in a 12 h :12 h light-dark schedule. The start of the lights-on period is defined as Zeitgeber time zero (ZT 0). Experiments were conducted according to National Institutes of Health guidelines for animal care and use and were approved by the Institutional Animal Care and Use Committee (IACUC) at the University of Iowa.
Sleep deprivation
All mice were single housed 7 days prior to the experiment with corncob bedding (Envigo, Teklad ¼” corncob, #7907) and soft bedding for nesting. Mice had ad libitum access to food and water during sleep deprivation. Mice were habituated for 5 days prior to the experiment by the researcher conducting the experiments. Habituation, performed in the behavior room for experiments, was done by holding each mouse in the palm for 2 min and then after returning to the home cage, tapping the cage for 2 min. Sleep deprivation was performed for 5 h from ZT 0 – ZT 5 using the gentle handling method32,33. Briefly, the experimenter tapped the side of the cage, as needed, to keep each mouse awake. When taps were no longer sufficient the mice received a light “cage shake” to rouse the animal. NSD mice remained in the colony housing room throughout the 5 h period.
Tissue processing and data generation
Each mouse was rapidly euthanized by cervical dislocation at ZT 5 with the whole brain rapidly extracted and flash frozen by ≥ −70 °C isopentane (n = 8 SD and n = 8 NSD). Frozen brains were stored at −80 °C. Prior to sectioning, a small tissue sample from the cerebellum of each frozen brain was removed, RNA extracted and quality assessed using RNA Integrity Number (RIN). Brains with a RIN above 7 were embedded in optimal cutting temperature medium (OCT) and cryosectioned at −20 °C (10μm sections) with the Leica CM3050 S Cryostat in the Iowa Neuroscience Institute (INI) NeuroBank Core. One coronal section per mouse, corresponding approximately to section 45 of the Paxinos Mouse Brain atlas, was mounted on Visium Spatial Gene Expression Slides (catalog no. 2000233, 10x Genomics). For tissue collection, we selected a slice that resembled section 45 of the Paxinos Mouse Brain Atlas based on the following features: the shape of the dentate gyrus and fit of CA1 and CA3 bands to the atlas; size and shape of fimbria; size and separation of optic tract and internal capsule; size of lateral ventricle. Sections were immediately processed with the 10x Genomics Visium Gene Expression Slide kit. Full details on the methods used are found in the manufacturer’s instructions (CG000239 Rev A User Guide Visium Spatial Gene Expression Reagent Kits). First, the slides were fixed in chilled methanol at −20 °C then stained with hematoxylin and eosin (H&E) to visualize the slices. Brightfield images of the H&E-stained sections were acquired (20X) using an Olympus BX61 Upright Microscope. Raw images were stitched together with the CellSens software (Version 3.2; Olympus) and exported as tiff files. Tissue was then permeabilized with Permeabilization Enzyme (provided by 10X Genomics in the Visium Gene Expression Slide & Reagent Kit, PN-1000184) for 18 min as determined based on tissue optimization time-course experiments. Permeabilization resulted in the release of polyA mRNA from the tissue enabling capture by poly(dT) primers precoated on the Visium Gene Expression slides. Slides also contained barcoded probes with unique molecular identifiers (UMI) so that the spatial gene distribution was mapped. After reverse transcription and second strand synthesis, the amplified cDNA samples from the slides were transferred, purified, and quantified for library preparation. Sequencing libraries were prepared by the Iowa Institute of Human Genetics (IIHG) Genomics Division, according to the Visium Spatial Gene Expression User Guide. Libraries were pooled for sequencing to achieve sequencing depth balance across the samples based on the relative area of coverage of each tissue on the slide. The fragmented cDNA pools were sequenced using an Illumina NovaSeq 6000 SP or S1 flowcell running 100 cycle SBS chemistry v1.5 and aimed for 200 million total read pairs. Read 1 was 48 nucleotide length (10 nt i5 index + 10 nt i7 index + 28 nt Spatial Barcode, UMI) and read 2 was 90 nucleotides length (insert).
Data processing
Raw FASTQ files and histology images were processed with the Space Ranger software v.1.3.1, which uses STAR v.2.7.10a for genome alignment against the Cell Ranger mm10 reference genome refdata-gex-mm10-2020-A, available at: https://cf.10xgenomics.com/supp/spatial-exp/refdata-gex-mm10-2020-A.tar.gz. QC metrics returned by this software are available in Supplementary Table 1. Quantification and statistical analysis were done with Partek Flow package (Build version 10.0.21.0621) in the Iowa Institute of Human Genetics (IIHG) Genomics Division. Briefly, to avoid raw gene expression counts of 0, a value of 0.001 was added to all counts prior to running SCTransform for normalization and scaling steps. Interpretation of spatial transcriptomic data requires effective preprocessing and normalization to remove spot-to-spot technical variability such as the number of molecules detected in each spot, which can confound biological heterogeneity with technical effects. Recently, a modeling framework for normalization and variance stabilization of molecular count data was made available for spatial datasets, which improves downstream analytical tasks including gene selection, dimensional reduction, and differential expression68 from spatial datasets. After applying this modeling framework, the dimensionality of each sample was reduced using 100 principal components from the variance of the features. A graph-based clustering was performed to identify the transcriptional signatures of each spot using the Louvain clustering algorithm that includes 30 nearest neighbors and 20 principal components. The Louvain algorithm is an unbiased approach connecting each sample spot to its nearest neighbor. The strength of the connections is weighted based on the similarity between the spots, and higher weight is given to spots more closely related. We then applied the Louvain algorithm to identify “communities” of spots that are more connected to spots in the same community than they are to spots of different communities, resulting in clustering of the sample spots. The threshold of 20 principal components was chosen based the elbow plot of each sample where most of the transcriptional variation was captured within the first 20 principal components (Supplementary Fig. 8).
The identification of anatomical brain regions for all 16 samples can be found in Supplementary Fig. 2. SCTransform algorithm yields a clearer representation of the different brain regions than a classic log-transformation (Supplementary Fig. 9). However, it is not suitable for differential gene expression analyses, as previously the SCTransform algorithm has been shown to result in ten times more significant false positives when used for differential gene expression analysis69. To overcome this challenge, output data from the Space Ranger pipeline were renormalized with the log transformation approach including Counts Per Million (each gene’s raw read count in a sample divided by the total number of counts per million in a sample), with a value of 1 added to avoid 0 counts and errors in differential analysis, and finally a log base 2 transformation applied to all values to model and measure proportional fold changes. This normalization revealed similar counts variation across samples (Supplementary Fig. 10). The cluster and brain region labels previously computed by the SCTransform algorithm were then transferred to this log-transformed data. Differential gene expression analysis was performed using the non-parametric Kruskal–Wallis rank sum test because the distribution of the counts does not conform to a normal or binomial distribution (Supplementary Fig. 11). Rank-sum tests have been the most widely used approach in the field of single-cell transcriptomics70 because it is assumed that every cell (or spot for spatial transcriptomics) is an identical replicate that defines the sample size of the statistics and this approach generates fewer false positives. In this study, the Kruskal–Wallis test was able to assign a median count of 1 (or 0 in log2), for both conditions, for a gene that is not expressed in a given brain region resulting in a fold change of 1 (or 0 in log2) (Supplementary Data 2, differential gene expression analysis in each brain region). Therefore, a gene was considered significantly differentially expressed (DE) if it has a false discovery rate (FDR) step-up (p-value adjusted) below 0.001 and a log2fold-change ≥ |0.2 | .
Addressing concerns regarding the potential for false negatives, we conducted a thorough assessment of the power of our spatial transcriptomic approach. We maintained a robust sequencing depth, with an average of 30,000 UMI counts per spatial spot within the neocortex, consistently across samples and specific neocortical layers such as layer 2/3 (Supplementary Fig. 12). Minimal variability in UMI counts was observed between samples and within the neocortex and neocortical layer 2/3, underscoring the reliability and reproducibility of our methodology (Supplementary Fig. 13). Notably, we identified 12 DEGs common to each neocortical layer after sleep deprivation. The UMI variability of these sleep responsive DEGs did not differ from that of 12 genes unaffected by sleep deprivation in the neocortical layers (Supplementary Fig. 14). This comparative analysis provides strong evidence against false positives, supporting the interpretation that our findings reflect genuine biological changes rather than artifacts.
Deconvolution: integration with single-cell data
At 55 µm, spots from the Visium platform encompass the expression profiles of 10–20 cells and represent averaged expression of the heterogeneous mixture of cells at the spot level. For this reason, computational techniques called deconvolution have been developed that use scRNA-seq data to infer cell proportions in bulk transcriptomic samples71. Consequently, deconvolution of each of the spatial voxels was performed to predict the underlying composition of cell types. We used a reference scRNA-seq dataset of ~14,000 adult mouse cortical cell taxonomy from the Allen Institute51. We applied the anchor-based integration that enables the probabilistic transfer of annotations from a reference to a query set, here it is our SCTransformed gene expression matrix output from Partek Flow®. We then took advantage of the SCTransform normalization to label transfer the cell-type identification of scRNA-seq clusters into the transcriptional signatures of the spatial voxels. The voxels with the highest prediction score were labeled and transferred to the log-transformed data for downstream differential gene expression analysis. The deconvolution of all 16 samples can be found in Supplementary Fig. 5.
GO molecular function enrichment analyses of differentially expressed genes (DEGs)
The ClueGO72 and CluePedia73 plug-ins of the Cytoscape 3.9.0 software74 were used in “Functional analysis” mode for analyzing the Gene Ontology Molecular Function (4691 terms) database in networks for DEGs. The names of significant DEGs were pasted into the “Load Marker List” of ClueGO, and the organism “Mus Musculus [10090]” was selected. Only pathways with a p < 0.05 were displayed on the figures (Supplementary Data 4). The GO Term Fusion was used allowing for the fusion of GO parent-child terms based on similar associated genes. The GO Term Connectivity had a kappa score of 0.4. The enrichment was performed using a two-sided hypergeometric test. The p-values were corrected with a Bonferroni step down approach.
Data and spot preprocessing for STANLY
We inspected all 16 samples visually, excluding any with serious tissue damage or a large amount of tissue folding after adhesion to the slide limiting our analysis to 13 samples. Samples were collected from the left or right hemisphere, but to maximize spatial similarity, we mirrored the right hemisphere samples (2) to the left hemisphere, so that all samples could be aligned in the left hemisphere space. After importing the image data of the slice along with the filtered feature matrix, we reduced the list of spots per slice down to only those listed as “in tissue” by Space Ranger and masked the filtered feature matrix for each sample to first remove empty non-tissue spots. We further removed from the analysis any in tissue spots that had fewer than 5000 total gene counts, which might indicate an error with the spot itself. Any genes that expressed 0 total reads across an entire sample were removed due to low statistical viability. For these 13 samples, the average number of in tissue spots per slide was 2548. Given the localized nature of gene expression to certain tissues or regions of a sample, raw gene counts in each spot are likely to be correlated to their neighbors, but not necessarily across an entire sample. This leads to a high likelihood of a right tail distribution of data when genes are regionally expressed, with potentially high counts in some spots and counts of zero in others. In order to account for this distribution of data, we performed log base 2 normalization on the raw gene counts being fed into the analysis. Log base2 normalization is specifically useful in the case of biological data such as gene counts as this normalizes the data to look for proportional rather than additive changes in expression. STANLY uses 7 neighboring spots in each calculation to account for spatial uncertainty, which is an inevitable problem for every alignment process. Importantly, every spot retains its original log base 2 value, and all 7 spots are utilized in our t-statistics. This strategy reduces spurious findings based on small misalignments.
While this basic principle—the alignment of individual data sets to a common template—is applicable to all kinds of multiomics data sets75, this version of STANLY has been optimized for the data sets in this study (e.g., regarding resolution, the number of dots, etc.).
Image preprocessing
Our data was collected as coronal slices of the mouse brain, chosen to be similar to slice 45 in the Paxinos Mouse Atlas, which is similar to Allen Brain Atlas slice 70, so as a template, we chose slice 70 from the Allen Common Coordinate Framework30. The code base for image preprocessing steps were performed using SimpleITK76 (v.5.3.0) and scikit-image77 (v.0.19.3) as well as SciPy78 (v.1.7.3) and NumPy79 (v.1.21.5) for processing the filtered feature matrices from Space Ranger and performing analysis on the registered spots.
For our current pipeline, most coronal tissue adhered to the slide in such a way that a simple rotation of [0°, 90°, 180, or 270°] is sufficient to bring the tissue images into the same general orientation as the template image. For those images from the right hemisphere, we additionally performed a symmetrical flip on the images and their corresponding spots to match the hemisphere of the template image. This hemisphere combination allows us to maximize the usability of tissue slices in the analysis. Any rotation or mirroring transformation to the tissue image is applied also to the spot coordinates so that these maintain the same space throughout processing. One common problem when trying to register different image modalities is how to handle differences in voxel resolution. In the platform used, we know the size of each spot (55 µm) as well as their distance on center from each other (100 µm). Using the image spot scaling information provided by Space Ranger, we can accurately calculate the size of each spot in the original high-resolution image and calculate the voxel to real world resolution and bring the image into the same resolution as the template. To perform the registration, the tissue image is converted to gray scale. The template image is also min-max normalized to bring it into range of a normal gray scale image rather than the original multi-channel image. To mask the background noise from the sample images we ran a 20 µm Gaussian blur on each image, from which we generated a binary tissue mask using the Otsu method, which allows us to mask out all voxels except for those that contain tissue from the registration process.
Image registration
After the initial rotation, we selected a single image from our sample set to act as our “best fit.” For the best fit, we chose a sample that had good shape and image quality. This selection of a best fit image is done to minimize the need of registering each sample individually to the template image, which has a higher potential for error, and instead register them all to the best fit image that shares more of the image characteristics of H&E stains. To run the registration of the best fit sample (Fig. 5A1) and its spots (Fig. 5A2) to the CCF template image (Fig. 5A3) we used the symmetric image normalization method (SyN) nonlinear registration tools from Advanced Normalization Tools (ANTs)80 (v.2.3.2), specifically the SyNAggro transformation using a mattes SyN metric with parameters of: SyN sampling = 32, flow sigma = 3, gradient step = 0.1, and registration iterations = [120, 100,80,60,40,20,0]. The result of this registration can be seen applied to the tissue image (Fig. 5A4) and to the tissue spots (Fig. 5A5). After the best fit image was registered to the CCF template image, we used the same registration parameters to register the remaining samples to the unregistered best fit image, and then finally applied “best fit to template” transformation generated above to each sample and its spots, bringing them into common space (Fig. 5A6).
Digital spots
With all sample images and their spot coordinates in the CCF reference space, we developed a method to create “digital spots” to make running analysis on multiple samples simpler and more closely representative of spacing of the spots in relation to each other. Visium spots are organized in a honeycomb arrangement, where each 55 µm spot has 6 equidistant nearest neighbors spaced 100 µm away on center. Knowing this, we created digital spots that replicate the characteristics of the platform spots in the digital space. Using the 10 µm resolution of the CCF template, we wrote a function that generated a honeycomb spaced grid of digital spots in CCF space and within the bounds of our template mask by defining the desired spacing between digital spots. Due to inevitable spatial uncertainty during registration, we set the spot spacing of our digital sampling to 150 µm in order to “smooth” the data, a method already common in neuroimaging. We then measured Euclidean distance between each digital spot and template registered tissue coordinates from all samples in the experiment. We sorted these distances and selected at each digital spot from each sample the 7 nearest neighbor spots up to 450 µm, or approximately 3 digital spots away from the center of the digital spot. We chose 7 because of the hexagonal properties of the spot spacing, with every 1 spot having 6 nearest neighbors. Each digital spot is, therefore, a vector of multiple spots from each of the registered samples, e.g., for our 13 samples, this sampling would include up to 7 × 13 sample spots at each digital spot. For our data, this method generated 2052 spots for the CCF template image (Fig. 5A7), of which we removed 160 spots from analysis for not having sufficient nearest neighbors across samples, leaving 1892 spots. Examples of this sampling can be seen in Fig. 5B–G, with the first image in each plot showing the mean of the digital spots of log base 2 normalized gene counts for NSD samples (Fig. 5B1–G1), the second image showing the mean of normalized gene counts for SD (Fig. 5B2–G2).
Statistical analysis of digital spots
We performed a two-tailed t-test on each digital spot with a Šidák p-value correction (Šidák, 1967) for the number of genes as follows: αs = 1 – (1 – α)(1/m). Where αs is the Šidák corrected p-value, α is the original p-value (and m is the number of genes in the transcriptome, n = 18,893). Based on these numbers, any genes that differed between NSD and SD with a p < 2.71e-06 was considered significantly differentially expressed.
The results of the two-tailed t-test for 6 example DEGs can be found in Fig. 5 (Fig. 5B3–G3). We used the Šidák method for statistical analysis because it assumes that each test is independent of each other. However, we also tested the Bonferroni and Benjamini–Hochberg methods for FDR correction to verify the strength of the gene analysis. We found the same number of DEGs (413) for the Bonferroni correction as the Šidák, while the Benjamini–Hochberg generated 422 DEGs. The overlap of genes between the Šidák and Bonferroni correction was 100%, with the Benjamini–Hochberg including an additional 9 genes (Supplementary Fig. 15). Thus, spatial transcriptomics provides a robust data set for differential gene analysis irrespective of the method used to correct for multiple comparisons.
Functional enrichment analysis of DEGs using ToppGene
ToppFun, the functional enrichment analysis tool from ToppGene suite52 was run by pasting the list of 413 DEGs generated by STANLY into the ToppFun enrichment gene set and searching for an enrichment of GO: Molecular Functions, GO: Biological Processes, and Mouse Phenotypes (Supplementary Fig. 6).
RNAscope In situ hybridization
To validate the results derived from STANLY, we used RNAscope in situ hybridization to assess Arc mRNA expression in the hippocampus. RNAscope was performed using commercially available fluorescent reagent kits according to the manufacturer’s protocol (Advanced Cell Diagnostics, Inc). In brief, mice were subjected to acute sleep deprivation for 5 h using gentle handling (cage taps and cage shakes). Animals were euthanized by cervical dislocation 1 h after sleep deprivation. Non sleep deprived animals were also euthanized at the same time to eliminate any circadian effect. Brains were dissected from SD and control NSD mice at the same circadian time and fixed for 3 h using 4% paraformaldehyde in PBS at 4 °C. Brains were transferred to 30% sucrose in PBS and kept at 4 °C for 48–72 h. Brains were then cryosectioned at −20 °C (25 μM), with coronal slices placed in a cryoprotective solution (30% sucrose, 30% ethylene glycol in PBS) and stored at −20 °C. Sections were rinsed in cold 1xPBS and then mounted and dried on Superfrost Plus microscope slides (Fisher Scientific, Cat. #12-550-15). Tissue sections on slides were arranged to enable multiple sample conditions on each slide including positive and negative in situ controls, non-sleep deprived sections and sleep deprived sections. For in situ hybridization, slides were then submerged in 50% ethanol, 70% ethanol, and two 100% ethanol steps for 5 min each at room temperature. Slides were then pretreated with solution according to the manufacturer directions for 30 min, and then washed with 1xPBS twice. The probe RNAscope™ Mm-Arc-C3 (Cat No. 316911-C3) was hybridized to the slides for 2 h at 40 °C. Following hybridization, slides were washed twice with wash buffer at room temperature and then subjected to a series of hybridizations and washes with the AMP 1, AMP 2, AMP 3 and AMP 4 reagents as directed by manufacturer (ACD). Prolong diamond antifade mountant with DAPI (Thermofisher, Cat. # P36962) was used to protect sections and visualize nuclei. Hippocampi were imaged using Leica confocal microscopes.
Reporting summary
Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article.
Supplementary information
Source data
Acknowledgements
The study was supported by the National Institutes of Health R01 Grant (R01AG062398) to T.A. and L.C.Ly., the University of Iowa Hawkeye Intellectual and Developmental Disability Research Center (P50 HD 103556; L. Strathearn and T.A., multi-PIs), and the Hensing Brain and Behavior Fund as well as the Carver Trust. T.N.-J. was supported by the Andrew H. Woods Professorship. T.A. is the Roy J. Carver Chair of Neuroscience. The authors acknowledge Xiaowen Wang’s exceptional technical support from Partek Inc., which was crucial for Visium spatial RNAseq data analysis. Data presented herein were obtained at the Iowa NeuroBank Core in the Iowa Neuroscience Institute, and the Genomics Division in the Iowa Institute of Human Genetics, which is supported, in part, by the University of Iowa Carver College of Medicine.
Author contributions
T.A. designed the study with input from S.C., L.C.Ly. and T.N-J. E.N.W. performed the sleep deprivation and tissue collection. L.-C.Li. performed the tissue preparation for spatial transcriptomics. Y.V. and Z.P. performed the transcriptomic and statistical analysis with the advice and guidance of the senior authors. Z.P. and T.N-J. developed and wrote the code for the STANLY analysis. L.C.Ly. and E.N.W. performed the RNAscope, confocal microscopy and data analysis. Y.V., Z.P., L.C.Ly., and E.N.W. wrote the manuscript with input from all the authors.
Peer review
Peer review information
Nature Communications thanks Carlos Neves, Graham Diering and Robert Greene for their contribution to the peer review of this work. A peer review file is available.
Data availability
The spatial RNA-seq data has been deposited in the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) under accession number GSE222410. Data analysis and processing were performed using commercial code from Partek Flow package at https://www.partek.com/partek-flow/. Source data are provided with this paper. Two screenshots of the reference mouse Allen brain atlas (http://atlas.brain-map.org) were used in two figures. The coronal section image 72 was used in Fig. 1C. The coronal section image 70 from the Allen P56 Mouse Common Coordinate Framework (CCF) was used in Fig. 5A3 as well as a template for the alignment step in STANLY. A reference scRNA-seq dataset of ~14,000 adult mouse cortical cell taxonomy from the Allen Institute was used for deconvolution (DOI: 10.1038/nn.4216). The mm10 reference genome used for the alignment of the reads in spatial transcriptomic can be found here: https://cf.10xgenomics.com/supp/spatial-exp/refdata-gex-mm10-2020-A.tar.gz. Source data are provided with this paper.
Code availability
The code for the deconvolution analysis can be accessed through GitHub (https://github.com/YannVRB/Sleep-deprivation-spatial-transcriptomic.git). The code for STANLY and subsequent analysis can be accessed through GitLab (https://research-git.uiowa.edu/zjpeters/STANLY).
Competing interests
T.A. serves on the Scientific Advisory Board of EmbarkNeuro and is a scientific advisor to Aditum Bio and Radius Health. The other authors declare no conflicting interests.
Ethics approval
All procedures on mice in this study were approved by the Institutional Care and Use Committee at the University of Iowa.
Footnotes
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Contributor Information
Thomas Nickl-Jockschat, Email: thomas-nickl-jockschat@uiowa.edu.
Ted Abel, Email: ted-abel@uiowa.edu.
Supplementary information
The online version contains supplementary material available at 10.1038/s41467-023-42751-z.
References
- 1.Wheaton AG, Jones SE, Cooper AC, Croft JB. Short sleep duration among middle school and high school students—United States, 2015. Morb. Mortal. Wkly. Rep. 2018;67:85–90. doi: 10.15585/mmwr.mm6703a1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.McHill AW, Wright KP. Role of sleep and circadian disruption on energy expenditure and in metabolic predisposition to human obesity and metabolic disease. Obes. Rev. 2017;18(Suppl 1):15–24. doi: 10.1111/obr.12503. [DOI] [PubMed] [Google Scholar]
- 3.Hudson AN, Van Dongen HPA, Honn KA. Sleep deprivation, vigilant attention, and brain function: a review. Neuropsychopharmacology. 2020;45:21–30. doi: 10.1038/s41386-019-0432-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Krause AJ, et al. The sleep-deprived human brain. Nat. Rev. Neurosci. 2017;18:404–418. doi: 10.1038/nrn.2017.55. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Raven F, Van der Zee EA, Meerlo P, Havekes R. The role of sleep in regulating structural plasticity and synaptic strength: Implications for memory and cognitive function. Sleep. Med. Rev. 2018;39:3–11. doi: 10.1016/j.smrv.2017.05.002. [DOI] [PubMed] [Google Scholar]
- 6.Sabia S, et al. Association of sleep duration in middle and old age with incidence of dementia. Nat. Commun. 2021;12:2289. doi: 10.1038/s41467-021-22354-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Shi L, et al. Sleep disturbances increase the risk of dementia: a systematic review and meta-analysis. Sleep. Med. Rev. 2018;40:4–16. doi: 10.1016/j.smrv.2017.06.010. [DOI] [PubMed] [Google Scholar]
- 8.Wang C, Holtzman DM. Bidirectional relationship between sleep and Alzheimer’s disease: role of amyloid, tau, and other factors. Neuropsychopharmacology. 2020;45:104–120. doi: 10.1038/s41386-019-0478-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Wu H, Dunnett S, Ho Y-S, Chang RC-C. The role of sleep deprivation and circadian rhythm disruption as risk factors of Alzheimer’s disease. Front. Neuroendocrinol. 2019;54:100764. doi: 10.1016/j.yfrne.2019.100764. [DOI] [PubMed] [Google Scholar]
- 10.Musiek ES, Holtzman DM. Mechanisms linking circadian clocks, sleep, and neurodegeneration. Science. 2016;354:1004–1008. doi: 10.1126/science.aah4968. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Gaine ME, et al. Altered hippocampal transcriptome dynamics following sleep deprivation. Mol. Brain. 2021;14:125. doi: 10.1186/s13041-021-00835-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Nilsson EK, Boström AE, Mwinyi J, Schiöth HB. Epigenomics of total acute sleep deprivation in relation to genome-wide DNA methylation profiles and RNA expression. OMICS J. Integr. Biol. 2016;20:334–342. doi: 10.1089/omi.2016.0041. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Vecsey CG, et al. Genomic analysis of sleep deprivation reveals translational regulation in the hippocampus. Physiol. Genomics. 2012;44:981–991. doi: 10.1152/physiolgenomics.00084.2012. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Cirelli C, Tononi G. Gene expression in the brain across the sleep–waking cycle. Brain Res. 2000;885:303–321. doi: 10.1016/S0006-8993(00)03008-0. [DOI] [PubMed] [Google Scholar]
- 15.Cirelli C, Gutierrez CM, Tononi G. Extensive and divergent effects of sleep and wakefulness on brain gene expression. Neuron. 2004;41:35–43. doi: 10.1016/S0896-6273(03)00814-6. [DOI] [PubMed] [Google Scholar]
- 16.Cirelli C. Cellular consequences of sleep deprivation in the brain. Sleep. Med. Rev. 2006;10:307–321. doi: 10.1016/j.smrv.2006.04.001. [DOI] [PubMed] [Google Scholar]
- 17.Mackiewicz M, et al. Macromolecule biosynthesis: a key function of sleep. Physiol. Genomics. 2007;31:441–457. doi: 10.1152/physiolgenomics.00275.2006. [DOI] [PubMed] [Google Scholar]
- 18.Mongrain V, Spada FL, Curie T, Franken P. Sleep loss reduces the DNA-binding of BMAL1, CLOCK, and NPAS2 to specific clock genes in the mouse cerebral cortex. PLoS One. 2011;6:e26622. doi: 10.1371/journal.pone.0026622. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.Cirelli C, Tononi G. Differential expression of plasticity-related genes in waking and sleep and their regulation by the noradrenergic system. J. Neurosci. 2000;20:9187–9194. doi: 10.1523/JNEUROSCI.20-24-09187.2000. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Scarpa JR, et al. Cross-species systems analysis identifies gene networks differentially altered by sleep loss and depression. Sci. Adv. 2018;4:eaat1294. doi: 10.1126/sciadv.aat1294. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Gerstner JR, et al. Removal of unwanted variation reveals novel patterns of gene expression linked to sleep homeostasis in murine cortex. BMC Genomics. 2016;17:727. doi: 10.1186/s12864-016-3065-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Hor CN, et al. Sleep–wake-driven and circadian contributions to daily rhythms in gene expression and chromatin accessibility in the murine cortex. Proc. Natl Acad. Sci. 2019;116:25773–25783. doi: 10.1073/pnas.1910590116. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23.Delorme J, et al. Sleep loss drives acetylcholine- and somatostatin interneuron–mediated gating of hippocampal activity to inhibit memory consolidation. Proc. Natl Acad. Sci. 2021;118:e2019318118. doi: 10.1073/pnas.2019318118. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 24.Delorme J, et al. Hippocampal neurons’ cytosolic and membrane-bound ribosomal transcript profiles are differentially regulated by learning and subsequent sleep. Proc. Natl Acad. Sci. USA. 2021;118:e2108534118. doi: 10.1073/pnas.2108534118. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25.Method of the Year 2020: spatially resolved transcriptomics. Nat. Methods18, 1 (2021). [DOI] [PubMed]
- 26.Maynard KR, et al. Transcriptome-scale spatial gene expression in the human dorsolateral prefrontal cortex. Nat. Neurosci. 2021;24:425–436. doi: 10.1038/s41593-020-00787-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27.Dixon EE, Wu H, Muto Y, Wilson PC, Humphreys BD. Spatially resolved transcriptomic analysis of acute kidney injury in a female murine model. J. Am. Soc. Nephrol. 2022;33:279–289. doi: 10.1681/ASN.2021081150. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 28.Nerurkar SN, et al. Transcriptional spatial profiling of cancer tissues in the era of immunotherapy: the potential and promise. Cancers. 2020;12:2572. doi: 10.3390/cancers12092572. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 29.He B, et al. Integrating spatial gene expression and breast tumour morphology via deep learning. Nat. Biomed. Eng. 2020;4:827–834. doi: 10.1038/s41551-020-0578-x. [DOI] [PubMed] [Google Scholar]
- 30.Wang Q, et al. The Allen mouse brain common coordinate framework: a 3D reference atlas. Cell. 2020;181:936–953.e20. doi: 10.1016/j.cell.2020.04.007. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 31.Allen Institute for Brain Science (2004). Allen Mouse Brain Atlas, Mouse, P56, Coronal. Available from mouse.brain-map.org. Allen Institute for Brain Science (2011).
- 32.Graves LA, Heller EA, Pack AI, Abel T. Sleep deprivation selectively impairs memory consolidation for contextual fear conditioning. Learn. Mem. 2003;10:168–176. doi: 10.1101/lm.48803. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 33.Prince T-M, et al. Sleep deprivation during a specific 3-hour time window post-training impairs hippocampal synaptic plasticity and memory. Neurobiol. Learn. Mem. 2014;109:122–130. doi: 10.1016/j.nlm.2013.11.021. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 34.Terao A, Greco MA, Davis RW, Heller HC, Kilduff TS. Region-specific changes in immediate early gene expression in response to sleep deprivation and recovery sleep in the mouse brain. Neuroscience. 2003;120:1115–1124. doi: 10.1016/S0306-4522(03)00395-6. [DOI] [PubMed] [Google Scholar]
- 35.Puentes-Mestril C, et al. Sleep loss drives brain region-specific and cell type-specific alterations in ribosome-associated transcripts involved in synaptic plasticity and cellular timekeeping. J. Neurosci. 2021;41:5386–5398. doi: 10.1523/JNEUROSCI.1883-20.2021. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 36.Lyons, L. C., Chatterjee, S., Vanrobaeys, Y., Gaine, M. E. & Abel, T. Translational changes induced by acute sleep deprivation uncovered by TRAP-Seq. Mol. Brain13, 165 (2020). [DOI] [PMC free article] [PubMed]
- 37.Vecsey CG, et al. Sleep deprivation impairs cAMP signalling in the hippocampus. Nature. 2009;461:1122–1125. doi: 10.1038/nature08488. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 38.Cirelli C, Tononi G. Differences in gene expression between sleep and waking as revealed by mRNA differential display. Mol. Brain Res. 1998;56:293–305. doi: 10.1016/S0169-328X(98)00057-6. [DOI] [PubMed] [Google Scholar]
- 39.Thompson, C. et al. Molecular and anatomical signatures of sleep deprivation in the mouse brain. Front. Neurosci. 4, 165 (2010). [DOI] [PMC free article] [PubMed]
- 40.Benoy A, Dasgupta A, Sajikumar S. Hippocampal area CA2: an emerging modulatory gateway in the hippocampal circuit. Exp. Brain Res. 2018;236:919–931. doi: 10.1007/s00221-018-5187-5. [DOI] [PubMed] [Google Scholar]
- 41.Kesner RP. An analysis of dentate gyrus function (an update) Behav. Brain Res. 2018;354:84–91. doi: 10.1016/j.bbr.2017.07.033. [DOI] [PubMed] [Google Scholar]
- 42.Nakashiba T, et al. Young dentate granule cells mediate pattern separation whereas old granule cells contribute to pattern completion. Cell. 2012;149:188–201. doi: 10.1016/j.cell.2012.01.046. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 43.Nakazawa K, et al. Requirement for hippocampal CA3 NMDA receptors in associative memory recall. Science. 2002;297:211–218. doi: 10.1126/science.1071795. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 44.Remondes M, Schuman EM. Role for a cortical input to hippocampal area CA1 in the consolidation of a long-term memory. Nature. 2004;431:699–703. doi: 10.1038/nature02965. [DOI] [PubMed] [Google Scholar]
- 45.Place R, et al. NMDA signaling in CA1 mediates selectively the spatial component of episodic memory. Learn. Mem. 2012;19:164–169. doi: 10.1101/lm.025254.111. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 46.Yao Z, et al. A taxonomy of transcriptomic cell types across the isocortex and hippocampal formation. Cell. 2021;184:3222–3241.e26. doi: 10.1016/j.cell.2021.04.021. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 47.Bolsius YG, Meerlo P, Kas MJ, Abel T, Havekes R. Sleep deprivation reduces the density of individual spine subtypes in a branch-specific fashion in CA1 neurons. J. Sleep. Res. 2022;31:e13438. doi: 10.1111/jsr.13438. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 48.Spano GM, et al. Sleep deprivation by exposure to novel objects increases synapse density and axon–spine interface in the hippocampal CA1 region of adolescent mice. J. Neurosci. 2019;39:6613–6625. doi: 10.1523/JNEUROSCI.0380-19.2019. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 49.Havekes R, et al. Sleep deprivation causes memory deficits by negatively impacting neuronal connectivity in hippocampal area CA1. eLife. 2016;5:e13424. doi: 10.7554/eLife.13424. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 50.Shepherd GMG. Corticostriatal connectivity and its role in disease. Nat. Rev. Neurosci. 2013;14:278–291. doi: 10.1038/nrn3469. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 51.Tasic B, et al. Adult mouse cortical cell taxonomy revealed by single cell transcriptomics. Nat. Neurosci. 2016;19:335–346. doi: 10.1038/nn.4216. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 52.Chen J, Bardes EE, Aronow BJ, Jegga AG. ToppGene Suite for gene list enrichment analysis and candidate gene prioritization. Nucleic Acids Res. 2009;37:W305–W311. doi: 10.1093/nar/gkp427. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 53.Delorme JE, Kodoth V, Aton SJ. Sleep loss disrupts Arc expression in dentate gyrus neurons. Neurobiol. Learn. Mem. 2019;160:73–82. doi: 10.1016/j.nlm.2018.04.006. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 54.Lake BB, et al. Neuronal subtypes and diversity revealed by single-nucleus RNA sequencing of the human brain. Science. 2016;352:1586–1590. doi: 10.1126/science.aaf1204. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 55.Pfisterer U, et al. Identification of epilepsy-associated neuronal subtypes and gene expression underlying epileptogenesis. Nat. Commun. 2020;11:5038. doi: 10.1038/s41467-020-18752-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 56.Velmeshev D, et al. Single-cell genomics identifies cell type–specific molecular changes in autism. Science. 2019;364:685–689. doi: 10.1126/science.aav8130. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 57.Murdock, M. H. & Tsai, L.-H. Insights into Alzheimer’s disease from single-cell genomic approaches. Nat. Neurosci. 10.1038/s41593-022-01222-2 (2023). [DOI] [PMC free article] [PubMed]
- 58.Kulkarni A, Anderson AG, Merullo DP, Konopka G. Beyond bulk: a review of single cell transcriptomics methodologies and applications. Curr. Opin. Biotechnol. 2019;58:129–136. doi: 10.1016/j.copbio.2019.03.001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 59.Saura CA, Deprada A, Capilla-López MD, Parra-Damas A. Revealing cell vulnerability in Alzheimer’s disease by single-cell transcriptomics. Semin. Cell Dev. Biol. 2023;139:73–83. doi: 10.1016/j.semcdb.2022.05.007. [DOI] [PubMed] [Google Scholar]
- 60.Noya SB, et al. The forebrain synaptic transcriptome is organized by clocks but its proteome is driven by sleep. Science. 2019;366:eaav2642. doi: 10.1126/science.aav2642. [DOI] [PubMed] [Google Scholar]
- 61.Brüning F, et al. Sleep-wake cycles drive daily dynamics of synaptic phosphorylation. Science. 2019;366:eaav3617. doi: 10.1126/science.aav3617. [DOI] [PubMed] [Google Scholar]
- 62.Chen PB, et al. Mapping gene expression in excitatory neurons during hippocampal late-phase long-term potentiation. Front. Mol. Neurosci. 2017;10:39. doi: 10.3389/fnmol.2017.00039. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 63.Le Duigou C, Savary E, Kullmann DM, Miles R. Induction of anti-hebbian LTP in CA1 stratum oriens interneurons: interactions between group I metabotropic glutamate receptors and M1 muscarinic receptors. J. Neurosci. 2015;35:13542–13554. doi: 10.1523/JNEUROSCI.0956-15.2015. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 64.Tudor JC, et al. Sleep deprivation impairs memory by attenuating mTORC1-dependent protein synthesis. Sci. Signal. 2016;9:ra41–ra41. doi: 10.1126/scisignal.aad4949. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 65.Brown SP, Hestrin S. Intracortical circuits of pyramidal neurons reflect their long-range axonal targets. Nature. 2009;457:1133–1136. doi: 10.1038/nature07658. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 66.Kita T, Kita H. The subthalamic nucleus is one of multiple innervation sites for long-range corticofugal axons: a single-axon tracing study in the rat. J. Neurosci. 2012;32:5990–5999. doi: 10.1523/JNEUROSCI.5717-11.2012. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 67.Libedinsky, C. et al. Sleep deprivation alters valuation signals in the ventromedial prefrontal cortex. Front. Behav. Neurosci. 5, 70 (2011). [DOI] [PMC free article] [PubMed]
- 68.Hafemeister C, Satija R. Normalization and variance stabilization of single-cell RNA-seq data using regularized negative binomial regression. Genome Biol. 2019;20:296. doi: 10.1186/s13059-019-1874-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 69.Choudhary S, Satija R. Comparison and evaluation of statistical error models for scRNA-seq. Genome Biol. 2022;23:27. doi: 10.1186/s13059-021-02584-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 70.Squair JW, et al. Confronting false discoveries in single-cell differential expression. Nat. Commun. 2021;12:5692. doi: 10.1038/s41467-021-25960-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 71.Avila Cobos F, Alquicira-Hernandez J, Powell JE, Mestdagh P, De Preter K. Benchmarking of cell type deconvolution pipelines for transcriptomics data. Nat. Commun. 2020;11:5650. doi: 10.1038/s41467-020-19015-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 72.Bindea G, et al. ClueGO: a Cytoscape plug-in to decipher functionally grouped gene ontology and pathway annotation networks. Bioinforma. Oxf. Engl. 2009;25:1091–1093. doi: 10.1093/bioinformatics/btp101. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 73.Bindea G, Galon J, Mlecnik B. CluePedia Cytoscape plugin: pathway insights using integrated experimental and in silico data. Bioinforma. Oxf. Engl. 2013;29:661–663. doi: 10.1093/bioinformatics/btt019. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 74.Shannon P, et al. Cytoscape: a software environment for integrated models of biomolecular interaction networks. Genome Res. 2003;13:2498–2504. doi: 10.1101/gr.1239303. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 75.Kumar VJ, et al. Linking spatial gene expression patterns to sex-specific brain structural changes on a mouse model of 16p11.2 hemideletion. Transl. Psychiatry. 2018;8:1–13. doi: 10.1038/s41398-018-0157-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 76.Beare, R., Lowekamp, B. & Yaniv, Z. Image segmentation, registration and characterization in R with SimpleITK. J. Stat. Softw. 86, 8 (2018). [DOI] [PMC free article] [PubMed]
- 77.Walt, et al. scikit-image: image processing in Python. PeerJ. 2014;2:e453. doi: 10.7717/peerj.453. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 78.Virtanen P, et al. SciPy 1.0: fundamental algorithms for scientific computing in Python. Nat. Methods. 2020;17:261–272. doi: 10.1038/s41592-019-0686-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 79.Harris CR, et al. Array programming with NumPy. Nature. 2020;585:357–362. doi: 10.1038/s41586-020-2649-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 80.Avants BB, Epstein CL, Grossman M, Gee JC. Symmetric diffeomorphic image registration with cross-correlation: evaluating automated labeling of elderly and neurodegenerative brain. Med. Image Anal. 2008;12:26–41. doi: 10.1016/j.media.2007.06.004. [DOI] [PMC free article] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Availability Statement
The spatial RNA-seq data has been deposited in the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) under accession number GSE222410. Data analysis and processing were performed using commercial code from Partek Flow package at https://www.partek.com/partek-flow/. Source data are provided with this paper. Two screenshots of the reference mouse Allen brain atlas (http://atlas.brain-map.org) were used in two figures. The coronal section image 72 was used in Fig. 1C. The coronal section image 70 from the Allen P56 Mouse Common Coordinate Framework (CCF) was used in Fig. 5A3 as well as a template for the alignment step in STANLY. A reference scRNA-seq dataset of ~14,000 adult mouse cortical cell taxonomy from the Allen Institute was used for deconvolution (DOI: 10.1038/nn.4216). The mm10 reference genome used for the alignment of the reads in spatial transcriptomic can be found here: https://cf.10xgenomics.com/supp/spatial-exp/refdata-gex-mm10-2020-A.tar.gz. Source data are provided with this paper.
The code for the deconvolution analysis can be accessed through GitHub (https://github.com/YannVRB/Sleep-deprivation-spatial-transcriptomic.git). The code for STANLY and subsequent analysis can be accessed through GitLab (https://research-git.uiowa.edu/zjpeters/STANLY).