Error-prone nonhomologous end joining repair operates in human pluripotent stem cells during late G2.

ABSTRACT: Genome stability of human embryonic stem cells (hESC) is an important issue because even minor genetic alterations can negatively impact cell functionality and safety. The incorrect repair of DNA double-stranded breaks (DSBs) is the ultimate cause of the formation of chromosomal aberrations. Using G2 radiosensitivity assay, we analyzed chromosomal aberrations in pluripotent stem cells and somatic cells. The chromatid exchange aberration rates in hESCs increased manifold 2 hours after irradiation as compared with their differentiated derivatives, but the frequency of radiation-induced chromatid breaks was similar. The rate of radiation-induced chromatid exchanges in hESCs and differentiated cells exhibited a quadratic dose response, revealing two-hit mechanism of exchange formation suggesti

SUBMITTER: Bogomazova AN 

PROVIDER: S-EPMC3164367 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature