Error-free and error-prone DNA repair gene expression through reprogramming and passage in human iPS cells

Medical applications of human iPS cells(hiPSC) are evolving, but detailed elucidation of the mechanisms of reprogramming remains to be elucidated. Reprogramming is accompanied by an increase in the expression of related genes that maintain pluripotency, such as OCT3 /4 and NANOG. Also, through reprogramming, many CNVs and point mutation arise in genomes, which constitute a major barrier to the use of hiPSC for regenerative medicine. On the other hand, we recently found that DNA repair-related genes expression are altered through reprogramming, elevated expression of genes that accurately convey genomic information, such as homologous recombination (HR) and mismatch repair(MMR), and decreased expression of error-prone translesion Synthesis polymerase(TLS). Here, we confirmed this expression change in another cell-line, and further found that this expression change was maintained by overlapping passages as well as OCT3 /4 and NANOG. This suggests that changes in the expression of DNA repair-related genes associated with reprogramming and their maintenance may be new indicators of the quality control of cells exhibiting pluripotency.