Crosstalk between the RNA Methylation and Histone-Binding Activities of MePCE Regulates P-TEFb Activation on Chromatin

Cell Reports

Sravan K. Devanathan¹  Marvin Mercado²  Samantha B. Shelton²  Nathan S. Abell²  Blerta Xhemalçe²  Nakul M. Shah² 

[1] Department of Genetics, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305-5324, USA;Department of Molecular Biosciences, 2500 Speedway, Austin, TX 78712, USA;

关键词: RNAP II pausing;    pTEFb;    7SK;    non-coding RNA;    MePCE;    BCDIN3;   

DOI  :  10.1016/j.celrep.2018.01.028

来源: DOAJ

【 摘 要 】

Summary: RNAP II switching from the paused to the productive transcription elongation state is a pivotal regulatory step that requires specific phosphorylations catalyzed by the P-TEFb kinase. Nucleosolic P-TEFb activity is inhibited by its interaction with the ribonuclear protein complex built around the 7SK small nuclear RNA (7SK snRNP). MePCE is the RNA methyltransferase that methylates and stabilizes 7SK in the nucleosol. Here, we report that MePCE also binds chromatin through the histone H4 tail to serve as a P-TEFb activator at specific genes important for cellular identity. Notably, this histone binding abolishes MePCE’s RNA methyltransferase activity toward 7SK, which explains why MePCE-bound P-TEFb on chromatin may not be associated with the full 7SK snRNP and is competent for RNAP II activation. Overall, our results suggest that crosstalk between the histone-binding and RNA methylation activities of MePCE regulates P-TEFb activation on chromatin in a 7SK- and Brd4-independent manner.

【 授权许可】

Unknown