Seemingly redundant portions of the fruit fly genome may not be so redundant after all.
New findings from a Princeton-led team of researchers suggest that repeated instructional regions in the flies' DNA may contribute to normal development under less-than-ideal growth conditions by making sure that genes are turned on and off at the appropriate times. If similar regions are found in humans, they may hold important clues to understanding developmental disorders.
The research results, published in the July 22 issue of the journal Nature, add to the growing body of evidence that so-called "junk DNA" is anything but rubbish. The term "junk DNA" is commonly used to describe the portion of the genome that doesn't contain genes, which are pieces of DNA that code for the production of proteins and other molecules that have specific functions. The noncoding region is often surprisingly large; in humans, some 98 percent of the genome merits "junk" status. But according to David Stern, a Princeton professor in the Department of Ecology and Evolutionary Biology, scientists increasingly believe "junk DNA" is crucial for turning the information encoded in genes into useful products.
"Over the past 10 to 20 years, research has shown that instructional regions outside the protein-coding region are important for regulating when genes are turned on and off," said Stern, the senior scientist on the paper. "Now we're finding that additional copies of these genetic instructions are important for maintaining stable gene function even in a variable environment, so that genes produce the right output for organisms to develop normally."
Stern, along with Nicols Frankel, a postdoctoral research fellow at Princeton, and their collaborators focused their attention on instructional regions called enhancers. These regions play an important role in the process by which information encoded in genes is used to direct the synthesis of the proteins t
|Contact: Kitta MacPherson|