Meeting Abstract

P1.143  Sunday, Jan. 4  The Effect of Melanization on Desiccation Resistance and Thermotolerance in Drosophila melanogaster KOBEY, RL*; HOSHIZAKI, DK; GIBBS, AG; Univ. of Nevada, Las Vegas; NIDDK, National Institutes of Health; Univ. of Nevada, Las Vegas kobeyr@unlv.nevada.edu

Previous research with the genus, Drosophila, has identified variations in cuticle melanization along gradients of elevation and latitude. Melanization of the cuticle is the result of incorporation of quinones into the cuticle and produces a darker-body phenotype. These quinones react to form cross-links between proteins in the cuticle and may also be polymerized to form melanin. It has been hypothesized that melanization is an adaptation to both low-temperature stress and desiccation stress (water stress). Cross-linking of proteins may make the cuticle more hydrophobic, thus reducing the rate of transpiration through the cuticle. The darker-body phenotype associated with melanization is also hypothesized to increase cold hardiness by allowing the animals to absorb more heat from solar radiation. Evidence in favor of this hypothesis has been obtained for larger insects, such as butterflies and beetles, but the hypothesis has not been tested in insects as small as Drosophila. We are testing mutations that produce lighter or darker body phenotypes to determine if melanization contributes to desiccation resistance and/or cold hardiness in Drosophila melanogaster. Supported by NSF award IOS-0719591 to D.K.H.and A.G.G.