Like many fish species, the bluebanded goby switches sex in response to changes in its social environment. In a socially stable group, removal of the dominant male typically results in the dominant female changing sex to fill the void. During this process, the female experiences an array of behavioral changes and the transformation of her sex organs to male.
In the study, CBN researcher and Georgia State University biology professor Matthew Grober, PhD, CBN and Georgia State post-doctoral fellow Michael Black, PhD, and researchers Jacques Balthazart, PhD, and Michelle Baillien, PhD, of the Center for Cellular and Molecular Neurobiology at the University of Liege in Belgium, attempted to determine the correlation between behavior and sex hormone conversion in four groups of gobies: a control group of females; a control group of males; dominant females who were beginning to change to males; dominant females who recently changed sex to males.
The researchers measured the activity of aromatase, an enzyme that converts testosterone to estrogen, in the gonads and the brain. Previous studies have implicated aromatase in sexual development in a variety of vertebrates, including humans. The researchers found that dominant, sex-changing females and recently sex-changed males had lower brain aromatase levels than control females. Control males had the lowest brain aromatase levels and lower gonadal aromatase levels than all groups, except
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Contact: Poul Olson
biopeo@langate.gsu.edu
404-463-9433
Emory University Health Sciences Center
10-Oct-2005