PROVIDENCE, R.I. [Brown University] Fruit flies are notoriously short-lived but scientists interested in the biology of aging in all animals have begun to understand why some fruit flies live longer than others. They have documented a direct association between insulin and life span, for example, and have observed a tradeoff between prolific reproduction and longevity. A new study, which may have broad implications across species, ties those findings more closely together by tracing an insulin signaling cascade through to protein quality control in muscle tissue and shortened life span.
The central feature of the study published in the November 2013 issue of PLoS Genetics is the newly discovered role of the fruit fly equivalent of the mammalian protein complex activin. They found that it blocks the natural mechanism in muscle cells for cleaning out misfolded proteins, leading to a decline in muscle performance. In what scientists at Brown University think is no coincidence, blocking the activity of that activin equivalent, called dawdle, can lengthen a fly's life span by as much as 20 percent, about 10 days.
What excites the researchers is not that they can allow flies to stick around another week or two, but that the same fundamental proteins they have implicated in flies are "conserved" in evolution, meaning they also operate in mammals including humans.
"The ultimate goal of our research is to understand how certain molecular signaling pathways control aging across all species in general," said study lead author Hua Bai, a postdoctoral researcher in the ecology and evolutionary biology lab of Marc Tatar, professor of biology at Brown. "For now this research is in fruit flies, but we think it can be extended to human aging biology. This signaling is quite conserved evolutionarily."
From insulin to muscle
Bai, Tatar, and their co-authors began the study armed with the understanding that a reductio
|Contact: David Orenstein|