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Title: The GATA transcription factor/ MTA ‐1 homolog egr‐1 promotes longevity and stress resistance in Caenorhabditis elegans

Aging is associated with a large number of both phenotypic and molecular changes, but for most of these, it is not known whether these changes are detrimental, neutral, or protective. We have identified a conservedCaenorhabditis elegansGATA transcription factor/MTA‐1 homologegr‐1(lin‐40) that extends lifespan and promotes resistance to heat and UV stress when overexpressed. Expression ofegr‐1increases with age, suggesting that it may promote survival during normal aging. This increase in expression is dependent on the presence of the germline, raising the possibility thategr‐1expression is regulated by signals from the germline. In addition, loss ofegr‐1suppresses the long lifespan of insulin receptordaf‐2mutants. The DAF‐16 FOXO transcription factor is required for the increased stress resistance ofegr‐1overexpression mutants, andegr‐1is necessary for the proper regulation ofsod‐3(a reporter for DAF‐16 activity). These results indicate thategr‐1acts within the insulin signaling pathway.egr‐1can also activate the expression of its paralogegl‐27,another factor known to extend lifespan and increase stress resistance, suggesting that the two genes act in a common program to promote survival. These results identifyegr‐1as part of a longevity‐promoting circuit that changes with age in a manner that is beneficial for the lifespan of the organism.

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Journal Name:
Aging Cell
Medium: X Size: p. 329-339
["p. 329-339"]
Sponsoring Org:
National Science Foundation
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