University of Birmingham scientists have discovered that the gene DAF-16 plays an important part in determining the rate of aging and average lifespan of the laboratory worm Caenorhabditis elegans (C. elegans) and its close evolutionary cousins.

DAF-16 is found in many other animals, including humans, and it is possible that this knowledge could open up new avenues for altering ageing, immunity and resistance to stresses in humans. The research was published this week in PLoS One

Researchers compared longevity, stress resistance and immunity in four related species of worm. They also looked for differences in the activity of DAF-16 in each of the four species and found that they were all quite distinct in this respect. And, importantly, the differences in DAF-16 corresponded to differences in longevity, stress resistance and immunity between the four species – in general higher levels of DAF-16 activity correlated with longer life, increased stress resistance and better immunity against some infections.

"DAF-16 is part of a group of genes that drive the biological processes involved in ageing, immunity and responses to physical or environmental stresses. The fact that subtle differences in DAF-16 between species seem to have such an impact on ageing and health is very interesting and may explain how differences in lifespan and related traits have arisen during evolution," says Dr Robin May, who led the research team.

The research in Birmingham is now moving on to look at the way in which DAF-16 coordinates a complex network of genes in order to balance the differing needs of an individual's immune system over time.

"Research using model organisms that uncovers the biology underpinning ageing gives us the opportunity to understand some of the mechanisms that determine how humans age in a healthy, or at least normal, way," Professor Douglas Kell said. "It is very important to develop a good understanding of healthy ageing if we are to appreciate what happens to an older person's physiology when they become unwell or experience difficulties with everyday tasks such as recalling memories or moving around."

Citation: Amrit FRG, Boehnisch CML, May RC,  'Phenotypic Covariance of Longevity, Immunity and Stress Resistance in the Caenorhabditis Nematodes', PLoS ONE 5(4):
e9978; doi:10.1371/journal.pone.0009978