The Fanconi anemia pathway controls oncogenic response in hematopoietic stem and progenitor cells by regulating PRMT5-mediated p53 arginine methylation

The Fanconi anemia (FA) pathway is involved in DNA damage and other cellular stress responses. We have investigated the role of the FA pathway in oncogenic stress response by employing an in vivo stress-response model expressing the Gadd45 beta-luciferase transgene. Using two inducible models of oncogenic activation (LSL-K-ras(G12D) and Myc(ER)), we show that hematopoietic stem and progenitor cells (HSPCs) from mice deficient for the FA core complex components Fanca or Fancc exhibit aberrant short-lived response to oncogenic insults. Mechanistic studies reveal that FA deficiency in HSPCs impairs oncogenic stress-induced G(1) cell-cycle checkpoint, resulting from a compromised K-ras(G12D)-induced arginine methylation of p53 mediated by the protein arginine methyltransferase 5 (PRMT5). Furthermore, forced expression of PRMT5 in HSPCs from LSL-K-ras(G12D)/CreER-Fanca(-/-) mice prolongs oncogenic response and delays leukemia development in recipient mice. Our study defines an arginine methylation-dependent FA-p53 interplay that controls oncogenic stress response.