Tweedle Coat Fashions Stocky Flies
University of California, San Diego biologists have discovered that disruptions in genes they call Tweedles make fruit flies short and stout like Tweedledee and Tweedledum in Alice in Wonderland. They report in this week鈥檚 issue of the journal Proceedings of the National Academy of Sciences that a defective TweedleD protein in the outer coat of fly larvae makes them appear compressed.
鈥淚t鈥檚 not a trivial matter to put a shell on from the inside,鈥� explained Steven Wasserman, a professor of biology who headed the research team. 鈥淎n insect needs to build up the flexibility, strength and shape of each part before sealing the outside. If you鈥檝e ever peeled a golf ball, you realize there isn鈥檛 just one thing holding it all together. Each part contributes.鈥�
The researchers discovered 27 different Tweedle genes in fruit flies. The different proteins in the Tweedle family are found in different parts of the cuticle鈥攖he tough outer coat in fly embryos and larvae. The exact function of the Tweedles is not known, but the researchers think they strengthen the cuticle. Make one part too weak or too strong and the larvae end up resembling their namesake.
Tweedles may be good targets for novel insecticides, the researchers say, because the gene family appears to be unique to insects. 鈥淲e鈥檝e discovered Tweedle genes in all insect species we鈥檝e examined, but not in any other species,鈥� said Xiao Guan, a graduate student working with Wasserman and first author of the study.
Source: University of California, San Diego
