Zhao Xinyang, Jankovic Vladimir, Gural Alexander, Huang Gang, Pardanani Animesh, Menendez Silvia, Zhang Jin, Dunne Richard, Xiao Andrew, Erdjument-Bromage Hediye, Allis C David, Tempst Paul, Nimer Stephen D
Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
Genes Dev. 2008 Mar 1;22(5):640-53. doi: 10.1101/gad.1632608.
RUNX1/AML1 is required for the development of definitive hematopoiesis, and its activity is altered by mutations, deletions, and chromosome translocations in human acute leukemia. RUNX1 function can be regulated by post-translational modifications and protein-protein interactions. We show that RUNX1 is arginine-methylated in vivo by the arginine methyltransferase PRMT1, and that PRMT1 serves as a transcriptional coactivator for RUNX1 function. Using mass spectrometry, and a methyl-arginine-specific antibody, we identified two arginine residues (R206 and R210) within the region of RUNX1 that interact with the corepressor SIN3A and are methylated by PRMT1. PRMT1- dependent methylation of RUNX1 at these arginine residues abrogates its association with SIN3A, whereas shRNA against PRMT1 (or use of a methyltransferase inhibitor) enhances this association. We find arginine-methylated RUNX1 on the promoters of two bona fide RUNX1 target genes, CD41 and PU.1 and show that shRNA against PRMT1 or RUNX1 down-regulates their expression. These arginine methylation sites and the dynamic regulation of corepressor binding are lost in the leukemia-associated RUNX1-ETO fusion protein, which likely contributes to its dominant inhibitory activity.
决定性造血作用的发育需要RUNX1/AML1，在人类急性白血病中，其活性会因突变、缺失和染色体易位而改变。RUNX1的功能可通过翻译后修饰和蛋白质-蛋白质相互作用来调节。我们发现，RUNX1在体内被精氨酸甲基转移酶PRMT1甲基化，且PRMT1作为RUNX1功能的转录共激活因子。通过质谱分析和一种甲基精氨酸特异性抗体，我们在RUNX1与共抑制因子SIN3A相互作用且被PRMT1甲基化的区域内鉴定出两个精氨酸残基（R206和R210）。RUNX1在这些精氨酸残基上的PRMT1依赖性甲基化消除了其与SIN3A的结合，而针对PRMT1的短发夹RNA（或使用甲基转移酶抑制剂）则增强了这种结合。我们在两个真正的RUNX1靶基因CD41和PU.1的启动子上发现了精氨酸甲基化的RUNX1，并表明针对PRMT1或RUNX1的短发夹RNA会下调它们的表达。在白血病相关的RUNX1-ETO融合蛋白中，这些精氨酸甲基化位点以及共抑制因子结合的动态调节丧失，这可能导致了其显性抑制活性。
