Scientists identify gene for sexual behavior in male flies
A team of scientists from four universities has isolated the gene that controls most or all sexual behavior in male fruit flies. Their research is the first to pinpoint a single gene that works in the brain to govern nearly all aspects of a complex behavior in adult animals.
The scientists from Stanford, the University of Texas Southwestern Medical Center at Dallas, Brandeis University and Oregon State University report their findings in the Dec. 13 issue of the journal Cell.
They showed that the fru gene is:
"There has been speculation recently that no single gene could control a complex behavior. This work shows that a gene can do so at least in fruit flies," said Stanford biologist Bruce Baker, one of the four principal investigators of the study.
Co-authors include postdoctoral research fellow Stephen F. Goodwin and research associate Adriana Villella of Brandeis; postdoctoral fellow Anuranjan Anand of Stanford; and Diego H. Castrillon, formerly an M.D./Ph.D. student at UT Southwestern, now a resident in pathology at Brigham and Women's Hospital and Harvard University Medical School.
"These findings on fru provide a starting point for a whole host of other studies, to learn how sexual behavior and sexual orientation are specified by genes and controlled by the nervous system," Wasserman said.
"Our data so far suggest that fru is involved in interactions between a handful of specific brain cells that in some way direct the various steps of male courtship behavior and copulation," Taylor said. "This is an important tool here we have a gene that allows us to extract some behavioral element and then go into the nervous system and see how it is organized."
"This is a spectacular example of the value of open exchange at scientific conferences," said Wasserman. The labs joined forces at an international meeting when he and Baker realized that each of their groups had half the essential information needed to clone and understand the role of the fru gene. "We had a map, and they knew where the crucial point in the map was," Wasserman said. "To go on and understand how the gene works called for the skills of the other two labs as well."
"In any complex organism, brain formation and function must be controlled in part by genes," Hall said. "The question is not whether but how do the actions of a given gene influence some interesting aspect of behavior."
However, he said, "Even if a gene of this sort could be identified in humans, that does not mean it would solely 'determine' behavior. By definition, those actions are also influenced by upbringing and environment even in flies."
-By Janet Basu-
REPORTERS NOTE: There are several indirect ways in which genes have been found to affect a fly's sexual behavior. For example, last year NIH researchers made headlines when they altered a gene for eye color so that it was expressed in every cell in the fly's body. In some cells, the altered eye-color gene triggered abnormal changes so that male flies courted other males. In contrast, the Dec. 13 Cell paper reports on the characterization of a gene that works within a group of genes governing all aspects of fruit fly sex. The research shows that this gene normally acts in the central nervous system of all male flies to specify sexual behavior.
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To obtain a copy of the scientific paper in Cell call (617) 661-7057, ext. 138.