Researchers may have uncovered one of the universal causes of aging: A crucial type of protein that serves a double duty in organisms ranging from yeast to mice, and that becomes overwhelmed as the organism ages. The protein is charged both with repairing DNA damage and with regulating gene expression (so that, for example, a gene necessary for liver function doesn't suddenly get turned on in the brain), and a new study has shown that when the protein is busy repairing DNA, it can't perform its other task. Says lead author David Sinclair:
"One idea of why we age is that DNA becomes damaged or mutated.... But perhaps the main culprit is the effect of genes switching on and off, and that should be reversible" [Wired News].
About a decade ago, researchers identified a protein called Sir2 that zooms to the spot of broken DNA in yeast cells and repairs ...
