The DNA in our cells is constantly being damaged by heat, radiation and other environmental stresses, andÂ the enzyme systems that repair DNA are critical for life. A particularly toxic form of damage is the covalent attachment of a protein to DNA, which can be triggered by radiation or by anticancer drugs.
Emory biochemist Keith Wilkinson and colleagues have a paper this week in the journal eLife probing how a yeast protein called Wss1 is involved in repairing DNA-protein crosslinks. The researchers show how Wss1 wrestles with a protein tag called SUMO onÂ the site of the DNA damage, and how Wss1 and SUMO areÂ involved in the cleanup process.
Three interesting things about this paper:
*The paper grew out of first author Maxim Balakirevâ€™s sabbatical with Wilkinson at Emory. Balakirev’s home base is at the CEA (Alternative Energy and Atomic Energy Commission)Â in Grenoble, France.
* Since manyÂ cancer chemotherapy drugs induce protein-DNA cross links, an inhibitor of cross linkÂ repair could enhance those drugs’ effectiveness. On the other side of the coin, mutations in a human gene called Spartan, whose sequence looks similar to Wss1â€™s, cause premature aging and susceptibility to liver cancer. Whether the Spartan-encoded protein has the same biochemical activity as Wss1 is not yet clear.
*SUMOÂ stands for â€œsmall ubiquitin-like modifierâ€. The eLife digest has an elegant explanation of whatâ€™s happening: Read more