Project description: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.

2019-07-21 | GSE134441 | GEO

DNA bending facilitates the error-free DNA damage tolerance pathway and upholds genome integrity

Project description:DNA replication is sensitive to damage in the template. To bypass lesions and complete replication, cells activate recombination-mediated (error-free) and translesion synthesis-mediated (error-prone) DNA damage tolerance pathways. Crucial for error-free DNA damage tolerance is template switching, which depends on the formation and resolution of damage-bypass intermediates consisting of sister chromatid junctions. Here we show that a chromatin architectural pathway involving the high mobility group box protein Hmo1 channels replication-associated lesions into the error-free DNA damage tolerance pathway mediated by Rad5 and PCNA polyubiquitylation, while preventing mutagenic bypass and toxic recombination. In the process of template switching, Hmo1 also promotes sister chromatid junction formation predominantly during replication. Its C-terminal tail, implicated in chromatin bending, facilitates the formation of catenations/hemicatenations and mediates the roles of Hmo1 in DNA damage tolerance pathway choice and sister chromatid junction formation. Together, the results suggest that replication-associated topological changes involving the molecular DNA bender, Hmo1, set the stage for dedicated repair reactions that limit errors during replication and impact on genome stability. BrdU and proteins ChIP-chip analyses analysis were carried out as described (Bermejo et al., 2009). Labelled probes were hybridized to Affymetrix S.cerevisiae Tiling 1.0 (P/N 900645) arrays and processed with TAS software.

2014-01-28 | E-GEOD-46260 | biostudies-arrayexpress

Hematopoietic stem cell quiescence promotes error-prone DNA repair and mutagenesis.

Project description: Not available

| S-EPMC2924905 | biostudies-literature

Dysfunctional DNA repair pathway via defective FANCD2 gene engenders multifarious exomic and transcriptomic effects in Fanconi anemia.

Project description: Not available

| S-EPMC6305641 | biostudies-literature

Increased error-free DNA repair gene expression through reprogramming in human iPS cells.

Project description: Not available

| S-EPMC6606834 | biostudies-literature