Researchers have deciphered the novel molecular structure of a protein that plays a critical role in determining male or female physical characteristics. Although the research was done in the fruit fly, Drosophila melanogaster, the researchers say the findings have implications in humans because similar genes have recently been found in the human genome.
The researcher team -- composed of members from Case Western Reserve University's School of Medicine, University of Chicago, and Gryphon Sciences -- report their results in a paper in the July 17 issue of the journal Genes and Development.
The structure binds DNA to turn on or off male genes or female genes. The finding is representative of how genome sequences are enabling a new generation of studies based on how the encoded proteins control the information in the genome.
Deletions in the human genes, found on Chromosome 9, are associated with sex reversal in children with normal Y chromosomes. Such children have a high risk of developing cancer in one or both gonads. The gene, called "doublesex" in the fly for its complementary roles in males and females, is also present in a wide range of multicellular animals, from insects and worms to fish and mice. In the male fruit fly, mutations in this new signal lead to a female pattern of some parts of the nervous system and bisexual orientation. The human protein was found to bind to a genetic control element in a fruit fly gene, indicating broad similarities of this new male signal.
"This structure extends known sex-specific signals, such as from estrogen or testosterone. The presence of similar genes in diverse kinds of animals suggests its primordial origins as a male signal," said Michael Weiss, the paper's senior author, and professor and chair of biochemistry at CWRU's School of Medicine.
"The newly obtained genomes of humans and other animals have revealed families of related genes, some of which may control aspects of the body plan
Contact: George Stamatis
Case Western Reserve University