Life’s tough when you’re a C. elegans worm. You hatch, you molt, you reproduce (usually with yourself), and then you die, all within 2–3 weeks. But a talented team of researchers at Stanford has found a way to keep worms wriggling long after they normally go to the great compost heap in the sky.
Stanford’s Anne Brunet and coworkers conducted an RNAi screen in C. elegans to identify lifespan-regulating genes, and found that a deficiency in the ASH-2 trithorax complex, which trimethylates histone H3 at lysine 4 (H3K4), extended lifespan by as much as 30%. Looking into this effect even further, they discovered:
- A deficiency in RBR-2, an H3K4 demethylase, shortened lifespan
- ASH-2 is highly expressed in the germline
- Lifespan extension by ASH-2 deficiency requires an intact germline and mature eggs
These results suggest that too much H3K4 trimethylation (a mark associated with active chromatin) is bad for a worm’s longevity, and that the ability of ASH-2/RBR-2 to regulate lifespan is somehow linked to the reproductive system. This epigenetic control of the aging process means there may be, one day, a possibility to reverse some the effects of aging. See if H3K4 trimethylation in worms holds the key to the fountain of youth in Nature, June 2010.