Non canonical BRCA1 promotes cell survival via modulating PARP13-mediated SEC61G mRNA decay.

ABSTRACT: BRCA1, a well-known tumor suppressor, maintains genomic integrity by facilitating homologous recombination (HR) repair and protecting DNA replication forks. However, its roles beyond DNA repair and replication remain largely unexplored. Here, we demonstrate that BRCA1 interacts with the RNA-binding protein PARP13 in the cytoplasm of ovarian cancer cells, with DNA damage enhancing this interaction via DNA-PK. Notably, BRCA1/PARP13 association is essential for cell survival but does not influence DNA repair efficacy following DNA damage. Mechanistically, PARP13 binds and destabilizes the mRNA of the endoplasmic reticulum (ER) membrane protein SEC61G. Upon DNA damage, BRCA1 disrupts PARP13-mediated SEC61G mRNA decay, leading to SEC61G upregulation. Elevated SEC61G levels cause calcium leakage

SUBMITTER: Sun B 

PROVIDER: S-EPMC12500858 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature