Tetratricopeptide repeat factor XAB2 mediates the end resection step of homologous recombination.

ABSTRACT: We examined the influence of the tetratricopeptide repeat factor XAB2 on chromosomal break repair, and found that XAB2 promotes end resection that generates the 3' ssDNA intermediate for homologous recombination (HR). Namely, XAB2 is important for chromosomal double-strand break (DSB) repair via two pathways of HR that require end resection as an intermediate step, end resection of camptothecin (Cpt)-induced DNA damage, and RAD51 recruitment to ionizing radiation induced foci (IRIF), which requires end resection. Furthermore, XAB2 mediates specific aspects of the DNA damage response associated with end resection proficiency: CtIP hyperphosphorylation induced by Cpt and BRCA1 IRIF. XAB2 also promotes histone acetylation events linked to HR proficiency. From truncation mutation analysis, the

SUBMITTER: Onyango DO 

PROVIDER: S-EPMC4937314 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature