• Register
X
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

X

Leaving Community

Are you sure you want to leave this community? Leaving the community will revoke any permissions you have been granted in this community.

No
Yes

Involvement of SUMO modification in MBD1- and MCAF1-mediated heterochromatin formation.

Small ubiquitin-related modifiers, SUMO-2/3 and SUMO-1, are involved in gene regulation and nuclear structures. However, little is known about the roles of SUMO, in heterochromatin formation of mammalian cells. Here we demonstrate that SUMOs directly interact with human MCAF1, which forms complexes with either the methyl-CpG-binding protein MBD1 or SETDB1, which trimethylates histone H3 at lysine 9 (H3-K9) in the presence of MCAF1. Modification of MBD1 with either SUMO-2/3 or SUMO-1 facilitated the interaction between MBD1 and MCAF1, suggesting that SUMOylation links the methylation of DNA and histones. In a cultured human cell line, SUMOs were localized in MBD1- and MCAF1-containing heterochromatin regions that were enriched in trimethyl-H3-K9 and the heterochromatin proteins HP1beta and HP1gamma. Specific knockdown of either SUMO-2/3 or SUMO-1 induced dissociation of MCAF1, trimethyl-H3-K9, and the HP1 proteins from the MBD1-containing heterochromatin foci, suggesting a requirement for SUMOs for heterochromatin assembly. These findings provide insights into the roles of SUMOylation in the regulation of heterochromatin formation and gene silencing.

Pubmed ID: 16757475

Authors

  • Uchimura Y
  • Ichimura T
  • Uwada J
  • Tachibana T
  • Sugahara S
  • Nakao M
  • Saitoh H

Journal

The Journal of biological chemistry

Publication Data

August 11, 2006

Associated Grants

None

Mesh Terms

  • Animals
  • Cell Nucleus
  • CpG Islands
  • DNA-Binding Proteins
  • Epigenesis, Genetic
  • HeLa Cells
  • Heterochromatin
  • Humans
  • Mutation
  • Protein Binding
  • Rats
  • SUMO-1 Protein
  • Transcription Factors
  • Two-Hybrid System Techniques