Cell Reports (Jan 2024)

The FANCI/FANCD2 complex links DNA damage response to R-loop regulation through SRSF1-mediated mRNA export

  • Anne Olazabal-Herrero,
  • Boxue He,
  • Youngho Kwon,
  • Abhishek K. Gupta,
  • Arijit Dutta,
  • Yuxin Huang,
  • Prajwal Boddu,
  • Zhuobin Liang,
  • Fengshan Liang,
  • Yaqun Teng,
  • Li Lan,
  • Xiaoyong Chen,
  • Huadong Pei,
  • Manoj M. Pillai,
  • Patrick Sung,
  • Gary M. Kupfer

Journal volume & issue
Vol. 43, no. 1
p. 113610

Abstract

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Summary: Fanconi anemia (FA) is characterized by congenital abnormalities, bone marrow failure, and cancer susceptibility. The central FA protein complex FANCI/FANCD2 (ID2) is activated by monoubiquitination and recruits DNA repair proteins for interstrand crosslink (ICL) repair and replication fork protection. Defects in the FA pathway lead to R-loop accumulation, which contributes to genomic instability. Here, we report that the splicing factor SRSF1 and FANCD2 interact physically and act together to suppress R-loop formation via mRNA export regulation. We show that SRSF1 stimulates FANCD2 monoubiquitination in an RNA-dependent fashion. In turn, FANCD2 monoubiquitination proves crucial for the assembly of the SRSF1-NXF1 nuclear export complex and mRNA export. Importantly, several SRSF1 cancer-associated mutants fail to interact with FANCD2, leading to inefficient FANCD2 monoubiquitination, decreased mRNA export, and R-loop accumulation. We propose a model wherein SRSF1 and FANCD2 interaction links DNA damage response to the avoidance of pathogenic R-loops via regulation of mRNA export.

Keywords