Function of the MYND domain and C-terminal region in regulating the subcellular localization and catalytic activity of the SMYD family lysine methyltransferase Set5

ABSTRACT: SMYD lysine methyltransferases target histones and non-histone proteins for methylation and are critical regulators of muscle developmental and implicated in neoplastic transformation. They are characterized by a split catalytic SET domain and an intervening MYND zinc finger domain, as well as an extended C-terminal domain. Saccharomyces cerevisiae contains two SMYD family members, Set5 and Set6, which share similar structural elements with the mammalian SMYD proteins. Set5 is a histone H4 lysine 5, 8, and 12 methyltransferase, implicated in the regulation of stress responses and genome stability. While the SMYD proteins have diverse roles in cells, there are many gaps in our understanding of how these enzymes are regulated. Here, we performed mutational analysis of Set5, combined with phosphoproteomics, to identify regulatory mechanisms for its enzymatic activity and subcellular localization. Our results indicate that the MYND domain promotes Set5 chromatin association in cells and mediates its interaction with DNA. Phosphoproteomics revealed extensive phosphorylation of Set5 and phosphomimetic mutations enhance Set5 catalytic activity and diminish its ability to interact with chromatin in cells. These studies uncover multiple regions within Set5 that regulate its localization and methyltransferase activity and highlight potential avenues for understanding mechanisms controlling the diverse roles of SMYD enzymes.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

TISSUE(S): Whole Body

SUBMITTER: James Moresco  

LAB HEAD: Erin. M. Green

PROVIDER: PXD014756 | Pride | 2019-11-11

REPOSITORIES: Pride