Arginine methylation of the C-terminus RGG motif promotes TOP3B topoisomerase activity and stress granule localization.

ABSTRACT: DNA topoisomerase 3B (TOP3B) is unique among all mammalian topoisomerases for its dual activities that resolve both DNA and RNA topological entanglements to facilitate transcription and translation. However, the mechanism by which TOP3B activity is regulated is still elusive. Here, we have identified arginine methylation as an important post-translational modification (PTM) for TOP3B activity. Protein arginine methyltransferase (PRMT) 1, PRMT3 and PRMT6 all methylate TOP3B in vitro at its C-terminal arginine (R) and glycine (G)-rich motif. Site-directed mutagenesis analysis identified R833 and R835 as the major methylation sites. Using a methylation-specific antibody, we confirmed that TOP3B is methylated in cells and that mutation of R833 and R835 to lysine (K) significantly reduces TOP3B

SUBMITTER: Huang L 

PROVIDER: S-EPMC5888246 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature