MePCE promotes homologous recombination through coordinating R-loop resolution at DNA double-stranded breaks.

ABSTRACT: MePCE is a multifunctional protein that regulates the positive transcription elongation factor b (P-TEFb) partitioning between the nucleosol and chromatin. MePCE's role in sequestering P-TEFb in the nucleosol via the 7SK ribonuclear protein complex (RNPc) is clear, but its functions on chromatin remain obscure. We report that chromatin-associated MePCE interacts with R-loop processing and DNA repair factors. MePCE is recruited to DNA double-stranded breaks (DSBs), and MePCE depletion impairs DSB repair by homologous recombination (HR), decreases RAD51 loading, and enhances R-loop levels at AsiSI-induced DSBs at specific genomic locations. Besides decreasing specific R-loop processing factors and chromatin remodelers, MePCE depletion increases the interaction with R-loops of the other const

SUBMITTER: Devanathan SK 

PROVIDER: S-EPMC12261951 | biostudies-literature | 2025 Jun

REPOSITORIES: biostudies-literature