Multiple DSB Resection Activities Redundantly Promote Alternative End Joining-Mediated Class Switch Recombination.

ABSTRACT: Alternative end joining (A-EJ) catalyzes substantial level of antibody class switch recombination (CSR) in B cells deficient for classical non-homologous end joining, featuring increased switch (S) region DSB resection and junctional microhomology (MH). While resection has been suggested to initiate A-EJ in model DSB repair systems using engineered endonucleases, the contribution of resection factors to A-EJ-mediated CSR remains unclear. In this study, we systematically dissected the requirement for individual DSB resection factors in A-EJ-mediated class switching with a cell-based assay system and high-throughput sequencing. We show that while CtIP and Mre11 both are mildly required for CSR in WT cells, they play more critical roles in mediating A-EJ CSR, which depend on the exonuclease a

SUBMITTER: Sun X 

PROVIDER: S-EPMC8671047 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature