Environmental Temperature Differentially Modulates C. Elegans Longevity

The exploration of mechanisms underlying aging and longevity is a hotspot in scientific field. Aging process is characterized with physiological function decline and several aging-associated diseases, ultimately aging is ending with death. It has been shown that aging and longevity are tightly modulated by genetic and environmental factors. Temperature as one universal environmental stimulus, has essential effect on physiological function and behavioral output of all species, including longevity and aging process. A general belief is that lower temperatures extend lifespan, although higher temperatures shorten it. Though this ‘‘temperature law'' is widely accepted, it has not been extensively tested. As a classic model system, Caenorhabditis elegans has been used to study genetic and environmental factors mediated longevity modulation for decades.Here, we systematically evaluated the role of temperature in lifespan regulation in C. elegans. We found that, although exposure to low temperatures at the adult stage prolongs lifespan, low-temperature treatment at the larval stage surprisingly reduces lifespan. Interestingly, this differential effect of temperature on longevity in larvae and adults is mediated by the same thermosensitive TRP channel TRPA-1 that signals to the transcription factor DAF-16/FOXO. DAF-16/FOXO and TRPA-1 act in larva to shorten lifespan but extend lifespan in adulthood. And our whole-genome microarry data suggests that DAF-16/FOXO differentially regulates gene expression in larva and adult in a temperature-dependent manner. Our results not only suggest that temperature experience in the early life of C.elegans can induce a long-lasting effect on its late life, but also uncover complexity underlying temperature modulation of longevity, demonstrating that temperature differentially regulates lifespan at different stages of life.