|
|
"SUMO modification of human XRCC4 regulates its localization and function in DNA double-strand break repair."
|
Yurchenko V, Xue Z, Sadofsky MJ
|
Published March 1, 2006
in Mol Cell Biol
volume 26
.
Pubmed ID:
16478998
Abstract:
The nonhomologous end-joining (NHEJ) pathway is responsible for rejoining the majority of double-strand breaks in mammalian cells, including the programmed breaks introduced by V(D)J recombination. The regulation of the enzymatic activities associated with this recombination pathway is still largely unknown. Here we report that human XRCC4 (for X-ray cross-complementation group 4), a protein essential for NHEJ, is subject to posttranslational protein modification. The modifier peptide, SUMO, can be added to XRCC4 both in vitro and in vivo. The site of modification is mapped to lysine 210 by using specific mutagenesis. A protein mutated such that it cannot be SUMOylated remains localized in the cytoplasm rather than accumulating in the nucleus. Cells expressing only the mutated protein are radiation sensitive and fail to complete V(D)J recombination. Genetic fusion of the SUMO sequence to the C terminus of the mutant restores nuclear localization and radiation resistance. The modification may serve a regulatory role. Our finding fits with an emerging literature associating SUMO modification with the control of the repair and recombination associated with DNA breaks.
|
This publication refers to following REPAIRtoire entries:
Last modification of this entry: Oct. 6, 2010
Add your own comment!
There is no comment yet.
|