Susan Parkhurst, Ph.D., and Miriam Rosenberg, both of Fred Hutchinson's Basic Sciences Division, describe in the May 17 issue of Cell how a gene called Sir2, long studied in yeast and worms, has a counterpart in fruit flies that plays a dynamic role in the genetic regulation of early development.
"Because of the important role of the Sir2 gene to basic life functioning, this gene has been the focus of laboratories worldwide," said Parkhurst, a member of Fred Hutchinson's Basic Sciences Division.
"This finding represents a major step in understanding what the Sir2 gene does in a complex, multi-cellular system and further establishes the fruit fly as an important animal model for the study of cancer genetics in humans," she said.
Cancer is a disease of genetic mistakes. Errors in the DNA blueprint that cause single genes or entire chromosomal regions to switch off at the wrong time or turn on inappropriately can result in uncontrolled cell growth and malignancy. Understanding the mechanisms that turn genes on and off during normal development is crucial for decoding - and ultimately correcting - any flawed and potentially fatal operating instructions within cells that may lead to cancer and developmental defects.
Until now, the Sir2 gene, short for "silent information regulator No. 2," has been known to act as a silencer, quieting large regions of the genome for extended periods to shut down the production of proteins that are no longer needed in the course of early development.
For the first time, Parkhurst and colleagues report that in Drosophila, or fruit flies, Sir2 appears to play a dual role. It also acts as a repressor gene, turning off the short-term express
Contact: Kristen Woodward
Fred Hutchinson Cancer Research Center