Cross-talk between PRMT1-mediated methylation and ubiquitylation on RBM15 controls RNA splicing
- The University of Alabama at Birmingham, United States
- Memorial Sloan Kettering Cancer Center, United States
- Tsinghua University, China
- Cell Signaling Technology, Inc., United States
- The University of Georgia, United States
- University of Ottawa, Canada
- Zhengzhou - Henan Cancer Hospital, China
- University of Massachusetts Medical School, United States
- Tsinghua University, United States
Abstract
RBM15, an RNA binding protein, determines cell-fate specification of many tissues including blood. We demonstrate that RBM15 is methylated by protein arginine methyltransferase 1 (PRMT1) at residue R578 leading to its degradation via ubiquitylation by an E3 ligase (CNOT4). Overexpression of PRMT1 in acute megakaryocytic leukemia cell lines blocks megakaryocyte terminal differentiation by downregulation of RBM15 protein level. Restoring RBM15 protein level rescues megakaryocyte terminal differentiation blocked by PRMT1 overexpression. At the molecular level, RBM15 binds to pre-mRNA intronic regions of genes important for megakaryopoiesis such as GATA1, RUNX1, TAL1 and c-MPL. Furthermore, preferential binding of RBM15 to specific intronic regions recruits the splicing factor SF3B1 to the same sites for alternative splicing. Therefore, PRMT1 regulates alternative RNA splicing via reducing RBM15 protein concentration. Targeting PRMT1 may be a curative therapy to restore megakaryocyte differentiation for acute megakaryocytic leukemia.
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© 2015, Zhang et al.
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Cross-talk between PRMT1-mediated methylation and ubiquitylation on RBM15 controls RNA splicing
eLife 4:e07938.
https://doi.org/10.7554/eLife.07938
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