Preferential gene expression and epigenetic memory of induced pluripotent stem cells derived from mouse pancreas

Induced pluripotent stem cells (iPSCs) have been established from various somatic cell types. Accumulating evidence suggests that iPSCs from different cell sources have distinct molecular and functional properties. Here, we establish iPSC derived from mouse pancreas (Panc-iPSC) and compared their properties with those of iPSC derived from tail-tip fibroblast (TTF-iPSC). The metabolic profile differs between Panc-iPSC and TTF-iPSC, indicating distinct cell properties in these iPSCs. Expression of Pdx1, a marker of pancreas differentiation, is increased through formation of embryoid body (EB) in Panc-iPSC, but the level is similar to that in TTF-iPSC. In contrast, EBs derived from Panc-iPSC express liver-specific albumin (Alb) and alpha-fetoprotein (Afp) genes much more strongly than those from TTF-iPSC. Epigenetic analysis shows a different histone modification pattern between Panc-iPSC and TTF-iPSC. Promoter regions of Alb and Afp genes in Panc-iPSC are suggested to have a more open chromatin structure than those in TTF-iPSC, which also is seen in primary cultured pancreatic cells. Our data suggest that Panc-iPSC possesses distinct differentiation capacity from that of TTF-PSC, which may be influenced by epigenetic memory.