Meeting Abstract

P3.81  Tuesday, Jan. 6  Molecular Evolution of Damselfly Opsin Genes JANANANDA, B.G.*; WIKRAMANAYAKE, A.; BUTLER, M.; University of Miami; University of Miami; University of Hawaii at Manoa bhagya@bio.miami.edu

In the Hawaiian archipelago, Megalagrion damselflies have radiated, entering new breeding habitats independently at least six times and have evolved bright body coloration numerous times. We are investigating whether they have undergone visual system adaptations to shifts in the light environment. The visual pigments or the opsins are a group of light-sensitive, membrane-bound G protein-coupled receptors found in photoreceptor cells of the retina of the eye. Variation in amino acid sequences of the visual pigments is one potential source of variation in visual sensitivity among photoreceptors. We will examine amino acid changes and whether they are correlated with or precede habitat shifts. We cloned and sequenced the cDNAs of ultraviolet (UV) absorbing rhodopsin of five different Megalagrion species using RT-PCR. The UV sequences, each encoding 387 amino acids are 72-73% identical to the UV absorbing rhodopsin of Apis mellifera. Even among these very closely related species, we find several synonymous and nonsynonymous substitutions. We will test for adaptive evolution in different domains of the opsin protein, and whether evolutionary changes are correlated with shifts in light habitat and body coloration.