Mutant U2AF1-induced alternative splicing of H2afy(macroH2A1) regulates B-lymphopoiesis in mice

Autor: Kim, Sanghyun P., Srivatsan, Sridhar N., Chavez, Monique, Shirai, Cara L., White, Brian S., Ahmed, Tanzir, Alberti, Michael O., Shao, Jin, Nunley, Ryan, White, Lynn S., Bednarski, Jeff, Pehrson, John R., Walter, Matthew J.
Zdroj: Cell Reports; August 2021, Vol. 36 Issue: 9
Abstrakt: Somatic mutations in spliceosome genes are found in ∼50% of patients with myelodysplastic syndromes (MDS), a myeloid malignancy associated with low blood counts. Expression of the mutant splicing factor U2AF1(S34F) alters hematopoiesis and mRNA splicing in mice. Our understanding of the functionally relevant alternatively spliced target genes that cause hematopoietic phenotypes in vivoremains incomplete. Here, we demonstrate that reduced expression of H2afy1.1, an alternatively spliced isoform of the histone H2A variant gene H2afy, is responsible for reduced B cells in U2AF1(S34F) mice. Deletion of H2afyor expression of U2AF1(S34F) reduces expression of Ebf1(early B cell factor 1), a key transcription factor for B cell development, and mechanistically, H2AFY is enriched at the EBF1 promoter. Induced expression of H2AFY1.1in U2AF1(S34F) cells rescues reduced EBF1 expression and B cells numbers in vivo. Collectively, our data implicate alternative splicing of H2AFYas a contributor to lymphopenia induced by U2AF1(S34F) in mice and MDS.
Databáze: Supplemental Index