UNDERSTANDING the complex process of ageing was never going to be easy. But now a gene known to boost lifespan has also been found to have the opposite effect.
The SIR2 gene makes an enzyme that stabilises DNA, and yeast cells with extra copies of SIR2 live longer. Biotech firms have even incorporated it into anti-ageing drug development programmes. But this week Valter Longo and colleagues at the University of Southern California, Los Angeles, show that deleting the gene causes yeast cells to live five to six times as long (Cell, DOI: 10.1016/j.cell.2005.08.042).
Longo thinks SIR2 may block organisms from entering an extreme survival mode that has heightened levels of DNA repair.
To continue reading this article, subscribe to receive access to all of newscientist.com, including 20 years of archive content.