This article discusses a model that has been proposed for how female-specific transformer (tra) transcripts are sex-specifically spliced in calliphorids, which is very different from D. melanogaster.
The Calliphoridae or blow flies are a family of insects that occupy diverse habitats and perform important ecological roles, particularly the decomposition of animal remains. Some Calliphoridae species are also important in the forensic sciences, in agriculture (e.g. as livestock pests) and in medicine (e.g. maggot therapy). Calliphoridae provide striking examples in support of the hypothesis that sex determination regulatory gene hierarchies evolve in the reverse order, with the gene at the top being the most recently added. Unlike the model fly Drosophila melanogaster, where sex is determined by the number of X chromosomes, in the Australian sheep blow fly (Lucilia cuprina) sex is determined by a Y-linked male-determining gene (M). A different regulatory system appears to operate in the hairy maggot blow fly (Chrysomya rufifacies) where the maternal genotype determines sex. It is hypothesized that females heterozygous for a dominant female-determining factor (F/f) produce only female offspring and homozygous f/f females produce only sons. The bottom of the regulatory hierarchy appears to be the same in D. melanogaster and L. cuprina, with sex-specific splicing of doublesex transcripts being controlled by the female-specific Transformer (TRA) protein. (publisher abstract modified)
Downloads
Similar Publications
- Lessons Learned on the Methodological Challenges in Studying Rare Violent Incidents
- Identifying and Embedding Brokers into a Multi-tiered System of Services to Reduce the Bystander Effect Leading to a Reduction in School Violence: End of Grant Report
- The Role of the Internet and Social Media on Radicalization: What Research Sponsored by the National Institute of Justice Tells Us