Meeting Abstract
Color vision in freshwater fishes is important for individuals to efficiently detect information from the external environment. Adaptations of visual systems to different photic environments drive visually-mediated behaviors, which include foraging, predator avoidance, and mate choice. The spectral sensitivity of photoreceptor cells in the retina is determined by the visual pigment in the photoreceptor, which is made up of a chromophore and an opsin protein. In this ongoing study, standard molecular methods were used to evaluate genetic variation in opsin gene sequences and expression profiles for two species of pupfish, Cyprinodon variegatus and Cyprinodon rubrofluviatilis. Preliminary evidence from PCR and gene sequencing suggests that both species express RH1, SWS1, SWS2A, SWS2B, RH2, and LWS opsin genes. When sequences were compared to known tuning sites within the seven transmembrane regions of the opsin protein, there was no variation between the species of pupfishes in the amino acid sequences of the LWS, SWS2B, and RH1 opsin genes. Pupfish opsins did differ from closely related killifish at known tuning sites. This suggests that pupfish visual systems may be tuned to their environments. Understanding the genetics behind the visual system is important to evaluate visual communication within species of freshwater fish.
