Figure 5. Altered transcriptome in mOLs lacking Lmna.

(B) Volcano plot of differentially expressed genes (p < 0.05) in FACS mOLs isolated from 8-week-old Lmna mutant mice (Ndrg1-EGFP;Cnp^Cre/+;Lmna^fl/fl, n = 3) and control mice (Ndrg1-EGFP;Cnp^+/+;Lmna^fl/fl, n = 3). After quality control, the following samples were used for differential expression analysis: n = 2 Lmna mutant and n = 2 control samples. Red dots represent significantly upregulated genes (n = 668), and blue dots represent significantly downregulated genes (n = 538).

(C) Gene expression heatmaps of upregulated biological process Gene Ontology (GO) terms in significantly upregulated (red) or downregulated (blue) genes in Lmna mutant mOLs (Ndrg1-EGFP;Cnp^Cre/+;Lmna^fl/fl) compared with control cells (Ndrg1-EGFP;Cnp^+/+;Lmna^fl/fl). Genes annotated for the GO terms “cell migration,” “PDGFR signaling pathway,” and “modulation of synaptic transmission” are shown.

(C) Visualization of ATAC-seq peaks in control (n = 6, black) and Lmna mutant (n = 5, red) OLs at the distal intergenic region of Cd44. Data were visualized using the WashU Epigenome Browser. The scale on the y axis was selected for optimal visualization of peaks.

(D) Scatterplot of Cd44 transcript levels measured by real-time qPCR in RNA samples extracted from cultured OPCs isolated from WT (Cnp^+/+;Lmna^fl/fl) and Lmna mutant mice (Cnp^Cre/+;Lmna^fl/fl) and differentiated in vitro. Data were normalized to the geometric (GEO)-mean of Gapdh, 18S, and Wdr33 transcript levels. Data represent average levels ± SD, n = 3 independent cultures per group (***p < 0.001, two-tailed Student’s t test).

(E) Representative confocal images of the corpus callosum of WT (Cnp^+/+;Lmna^fl/fl) and Lmna mutant 26-week-old mice (Cnp^Cre/+;Lmna^fl/fl). Sections were stained with CD44 (green) and OLIG2 (red). DAPI (blue) was used as counterstain. Scale bar, 5 μm.

(F) Scatterplot of the number of CD44⁺/CC1⁺ cells per mm² corpus callosum in control mice (Cnp^+/+;Lmna^fl/fl, n = 3) and Lmna mutant mice (Cnp^Cre/+;Lmna^fl/fl, n = 3). Data represent average percentages ± SD (**p < 0.01, two-tailed Student’s t test).

(G) Heatmap of the transcript levels within the “mitochondrial inner membrane” GO category, showing downregulation (blue) in sorted mOLs lacking Lmna (Ndrg1-EGFP;Cnp^Cre/+;Lmna^fl/fl) compared with control cells (Ndrg1-EGFP;Cnp^+/+;Lmna^fl/fl).

(H) Scatterplot of the mitochondrial transcript Atp5e (C) and Ndufb5 (D) levels measured by real-time qPCR in RNA samples extracted from Lmna mutant (Cnp^Cre/+; Lmna^fl/fl) and control (Cnp^+/+;Lmna^fl/fl) OLs, differentiated in cultures from neonatal OPCs. Data were normalized to the geometric (GEO)-mean of Gapdh and Wdr33 transcript levels. Data are represented as mean ± SD, n = 3 independent cultures per group (*p < 0.05, **p < 0.01, two-tailed Student’s t test).

(I) Electron microscopy image of OLs in the ventral horn of the spinal cord of Lmna mutant (Cnp^Cre/+;Lmna^fl/fl) and control (Cnp^+/+;Lmna^fl/fl) mice. Scale bar, 1 μm. The insets represent higher-magnification images of the mitochondrial structure in OLs from mice of the two genotypes to highlight the loss of internal cristae definition in mOLs lacking LMNA. Scale bar, 0.5 μm.

See also Tables S1 and S2 and Figure S6.