Functional insights from high resolution structures of mouse protein arginine methyltransferase 6

• Published in: Journal of structural biology Vol. 191; no. 2; pp. 175 - 183
• Main Authors: Bonnefond, Luc, Stojko, Johann, Mailliot, Justine, Troffer-Charlier, Nathalie, Cura, Vincent, Wurtz, Jean-Marie, Cianférani, Sarah, Cavarelli, Jean
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-08-2015; Elsevier
• Subjects: Amino Acid Sequence; Animals; Biochemistry, Molecular Biology; Cloning, Molecular; Crystallography, X-Ray; Epigenetics; Life Sciences; Mass Spectrometry; Methylation; Methyltransferase; Mice; Models, Molecular; Molecular Sequence Data; PRMT6; Protein Folding; Protein structure; Protein Structure, Tertiary; Protein-Arginine N-Methyltransferases - chemistry; Protein-Arginine N-Methyltransferases - physiology; S-adenosyl-l-methionine; Sequence Alignment; Structure-Activity Relationship; PRMT6; Methyltransferase; ESI-MS; S-adenosyl-l-methionine; PRMT; LC–MS/MS; PDB; SFG; Epigenetics; rmsd; SAH; Protein structure; SAM
• ISSN: 1047-8477; 1095-8657
• DOI: 10.1016/j.jsb.2015.06.017

PRMT6 is a protein arginine methyltransferase involved in transcriptional regulation, human immunodeficiency virus pathogenesis, DNA base excision repair, and cell cycle progression. Like other PRMTs, PRMT6 is overexpressed in several cancer types and is therefore considered as a potential anti-cancer drug target. In the present study, we described six crystal structures of PRMT6 from Mus musculus, solved and refined at 1.34Å for the highest resolution structure. The crystal structures revealed that the folding of the helix αX is required to stabilize a productive active site before methylation of the bound peptide can occur. In the absence of cofactor, metal cations can be found in the catalytic pocket at the expected position of the guanidinium moiety of the target arginine substrate. Using mass spectrometry under native conditions, we show that PRMT6 dimer binds two cofactor and a single H4 peptide molecules. Finally, we characterized a new site of in vitro automethylation of mouse PRMT6 at position 7.