Figure 6. Neurochemical phenotypes of VTA Sst neurons according in situ mRNA hybridization and PatchSeq experiments.

(a) Example images of multichannel in situ hybridization RNAscope experiments, showing a variety of Sst neuron molecular subtypes, based on Sst, Slc6a3, Slc32a1 and Slc17a6 mRNA expressions. (b) Proportion of Sst neuron molecular subtypes, as classified and counted for coronal and horizontal sections of the VTA from adult wild-type C57BL/6J mice (n = 8). (c) Molecular subtypes, acquired by alignment of PatchSeq results to a bigger midbrain scRNASeq database, mapped on electrophysiological Sst-neuron clusters (see Figure 3a). Triangle in the right corner shows color-coding for the molecular subtypes. ADP and HFF clusters included mostly GABA or Glu+GABA neurons, whereas the Delayed cluster had a spectrum of DA-containing neurons. Supporting data can be found in the Additional files: Figure 6—source data 1. Figure 6—figure supplements 1–4.

Figure 6—figure supplement 1. Seurat clustering of the reference midbrain dataset and selection of the clusters for PatchSeq cells classification.

tSNE of the clustering results. Clusters highlighted with dark contours were used for the mapping procedure. Clusters 3, 5, 6, 7, 12 and 13 were selected due to Sst (panel b) and neuronal markers expression (panel c).

Figure 6—figure supplement 2. Sst expression in selected clusters 3, 5, 6, 7, 12 and 13.

Figure 6—figure supplement 3. Neuronal marker expression in selected clusters 3, 5, 6, 7, 12 and 13.

Figure 6—figure supplement 4. Expression of dopamine-related genes in different Sst-expressing neuronal populations in the VTA, indicating strong expression in Delayed cells.

Values are mean expression levels in read counts for n cells. For scaling, the values for Th were divided by 10.