H2BK120ub and its reader RNF169 sequentially regulate replication fork remodeling and stability.

ABSTRACT: Ubiquitination of the C-terminus of histone H2B (H2BK120ub) is a key histone modification with functions in a wide array of DNA-related processes, best characterized in gene transcription and repair. A role for H2B ubiquitination in DNA replication has been postulated and investigated in yeast but is still elusive in human cells. Here, we uncovered a critical function of H2BK120ub in replication fork dynamics. H2BK120ub is present at replication forks and accumulates upon replication stress in a manner dependent on ATR and RAD51. Loss of RNF20, the main ubiquitin ligase promoting H2BK120ub, leads to RECQ1-mediated unrestrained replication fork progression and defective fork reversal upon mild replication stress, restoring fork stability in BRCA2-deficient cells. Furthermore, we identified

SUBMITTER: Duzanic FD 

PROVIDER: S-EPMC12623888 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature