Sex determination is controlled by global regulatory genes, such as tra-1 in Caenorhabditis elegans, Sex lethal in Drosophila, or Sry in mammals. How these genes coordinate sexual differentiation throughout the body is a key unanswered question. tra-1 encodes a zinc finger transcription factor, TRA-1A, that regulates, directly or indirectly, all genes required for sexual development. mab-3 (mal...

The region of the third chromosome (84D-F) of Drosophila melanogaster that contains the doublesex (dsx) locus has been cytogenetically analyzed. Twenty nine newly induced, and 42 preexisting rearrangements broken in dsx and the regions flanking dsx have been cytologically and genetically characterized. These studies established that the dsx locus is in salivary chromosome band 84E1-2. In additi...

The mechanism of switching to sexual differentiation (gametocytogenesis) of Plasmodium falciparum appears to be controlled by stochastic mechanisms that are sensitive to environmental conditions. In any given conditions, only a proportion of genetically identical parasites will become committed to sexual development. We used an experimental co-culture system to detect the presence of diffusible...

BACKGROUND Among more than 20,000 species of hermaphroditic trematodes, Schistosomatidae are unusual since they have evolved gonochorism. In schistosomes, sex is determined by a female heterogametic system, but phenotypic sexual dimorphism appears only after infection of the vertebrate definitive host. The completion of gonad maturation occurs even later, after pairing. To date, the molecular m...

Much of the literature focuses on the pathology that falls to the far right of the Watkins (1997) differentiation-dissociation continuum, such as Dissociative Identity Disorder and Dissociative Disorder NOS. Adding a "far left" to this continuum, as well as a construct of what the "far left" looks like, makes apparent the value of healthy adaptive differentiation for those individuals that fall...

Understanding of the development of the reproductive organs is essential to the evaluation of abnormalities in sexual differentiation. Recent advances resulting from application of genetic, biochemical, and ultrastructural techniques have helped to clarify the mechanisms regulating gonadal and reproductive tract development. The present review considers the major processes of sexual differentia...

The importance of estrogens in controlling brain and behavioral sexual differentiation in female rodents is an unresolved issue in the field of behavioral neuroendocrinology. Whereas, the current dogma states that the female brain develops independently of estradiol, many studies have hinted at possible roles of estrogen in female sexual differentiation. Accordingly, it has been proposed that a...

Genetic exchange is common among bacteria, but its effect on population diversity during ecological differentiation remains controversial. A fundamental question is whether advantageous mutations lead to selection of clonal genomes or, as in sexual eukaryotes, sweep through populations on their own. Here, we show that in two recently diverged populations of ocean bacteria, ecological differenti...