Fig. 2: ScRNA-seq identifies DEGs in P2 β-cell subtypes.

Islets from P2 MNT mice were isolated, dissociated, and used in inDrop-seq. The β cells were then grouped as tdT⁺ and tdT^- sub-populations for comparison. a UMAPs showing the clustering of different cell types within islets (left) and the β-cell subtypes with tdT expression highlighted (right). b, c Terms enriched in the P2 tdT⁺ (b) and tdT^- (c) β-cell subtypes, analyzed using DAVID. The p-values, from one-sided Fisher’s exact tests, were adjusted using the Benjamini-Hochenberg procedure for multiple comparisons. d, e Heat maps of several genes that are not (d) or are (e) differentially expressed in tdT⁺ and tdT^- β cells. Log-transformed expression levels are presented, normalized against their mean across the four replicates. The samples are grouped based on tdT expression. The results of tdT⁺ and tdT^- cells within each replica (S1-S4) were also marked for pair-wise comparison. The large inter-sample variations between either tdT⁺ or tdT^- cells likely reflect the volatile nature of heterogeneity in individual mouse and batch differences of scRNA-seq. f, g Dnmt3a levels in β-cell subsets at P2. f An example of IF co-staining (average projection from Z-stack confocal images) of Dnmt3a (green) and insulin (white) in MNT islet cells. Yellow and red arrows, tdT⁺ or tdT^- cells, respectively. g The relative IF signal intensity in individual tdT⁺ or tdT^- β cell nuclei (2 batches done on two days, two mice each day), presented as an arbitrary unit (A.U.). Each dot represents an average of IF intensity of all beta cells examined in each mouse prep. “n” in g refers to the number of mice examined. The P-value is from an paired t-test with a two-sided type-two error. Scale bar, 20 μm.