PMID: 27480107

Authors:

Wu H, Zheng W, Eram MS, Vhuiyan M, Dong A, Zeng H, He H, Brown P, Frankel A, Vedadi M, Luo M, Min J

Title:

Structural basis of arginine asymmetrical dimethylation by PRMT6.

Journal:

Biochem J. 2016 Oct 1;473(19):3049-63. doi: 10.1042/BCJ20160537. Epub 2016 Aug 1.

Abstract:

PRMT6 is a type I protein arginine methyltransferase, generating the asymmetric dimethylarginine mark on proteins such as histone H3R2. Asymmetric dimethylation of histone H3R2 by PRMT6 acts as a repressive mark that antagonizes trimethylation of H3 lysine 4 by the MLL histone H3K4 methyltransferase. PRMT6 is overexpressed in several cancer types, including prostate, bladder and lung cancers; therefore, it is of great interest to develop potent and selective inhibitors for PRMT6. Here, we report the synthesis of a potent bisubstrate inhibitor GMS [6'-methyleneamine sinefungin, an analog of sinefungin (SNF)], and the crystal structures of human PRMT6 in complex, respectively, with S-adenosyl-L-homocysteine (SAH) and the bisubstrate inhibitor GMS that shed light on the significantly improved inhibition effect of GMS on methylation activity of PRMT6 compared with SAH and an S-adenosyl-L-methionine competitive methyltransferase inhibitor SNF. In addition, we also crystallized PRMT6 in complex with SAH and a short arginine-containing peptide. Based on the structural information here and available in the PDB database, we proposed a mechanism that can rationalize the distinctive arginine methylation product specificity of different types of arginine methyltransferases and pinpoint the structural determinant of such a specificity.