26.6 Monday, Jan. 5 Comparative transcriptome profiling provides novel insights into the evolutionary genetics of black widow spider venom. GARB, J.E.*; HAYASHI, C.Y.; ZINSMAIER, K.E.; University of Arizona; University of California, Riverside; University of Arizona email@example.com
Animal venoms are complex mixtures of toxins having diverse physiological activities, which can often evolve rapidly in response to selection imposed by predators or prey. Spiders are among the largest group of animals defined by venom production, yet the diversity and evolution of spider toxins have to date received little attention. We conducted a comparative analysis of venom proteins synthesized by the black widow spider (Latrodectus hesperus) and two closely related species using a variety of molecular techniques. From these three species, we constructed and screened venom gland cDNA libraries and performed genomic PCR and 3' RACE to examine the expression, genetic organization and phylogeny of putative toxin families. In addition, we compared substitution rates of toxin genes with those of mitochondrial and nuclear housekeeping genes to detect instances of rapid evolution. Our results have implications for understanding the evolution of vertebrate toxicity in black widow spiders as well as for identifying novel toxins with potential pharmaceutical applications.