Notably, JNK3 expression was increased in mice subjected to a high-fat diet (HFD) compared with a regular chow diet (21) (Supplemental Figure 1B) and the expression of all 3 isoforms was increased in pancreatic β cells from type 2 diabetic donors (Supplemental Figure 2A) and in Type 1 diabetes donors in a single-cell analysis (Supplemental Figure 3A), indicating the involvement of JNKs in β cell adaptation to diabetes. This evidence concerns the gene MAPK10 and diabetes mellitus.