title: Independent losses of visual perception genes Gja10 and Rbp3 in echolocating bats (Order: Chiroptera).
abstract: A trade-off between the sensory modalities of vision and hearing is likely to have occurred in echolocating bats as the sophisticated mechanism of laryngeal echolocation requires considerable neural processing and has reduced the reliance of echolocating bats on vision for perceiving the environment. If such a trade-off exists, it is reasonable to hypothesize that some genes involved in visual function may have undergone relaxed selection or even functional loss in echolocating bats. The Gap junction protein, alpha 10 (Gja10, encoded by Gja10 gene) is expressed abundantly in mammal retinal horizontal cells and plays an important role in horizontal cell coupling. The interphotoreceptor retinoid-binding protein (Irbp, encoded by the Rbp3 gene) is mainly expressed in interphotoreceptor matrix and is known to be critical for normal functioning of the visual cycle. We sequenced Gja10 and Rbp3 genes in a taxonomically wide range of bats with divergent auditory characteristics (35 and 18 species for Gja10 and Rbp3, respectively). Both genes have became pseudogenes in species from the families Hipposideridae and Rhinolophidae that emit constant frequency echolocation calls with Doppler shift compensation at high-duty-cycles (the most sophisticated form of biosonar known), and in some bat species that emit echolocation calls at low-duty-cycles. Our study thus provides further evidence for the hypothesis that a trade-off occurs at the genetic level between vision and echolocation in bats.
authors.affiliation: Institute of Molecular Ecology and Evolution, Institutes for Advanced Interdisciplinary Research, East China Normal University, Shanghai, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Shen
authors.forename: Tao
authors.initials: T
authors.lastname: Fang
authors.forename: Mengyao
authors.initials: M
authors.lastname: Dai
authors.forename: Gareth
authors.initials: G
authors.lastname: Jones
authors.forename: Shuyi
authors.initials: S
authors.lastname: Zhang
mesh_terms: D000220:Adaptation, Biological / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002685:Chiroptera / Q000235:genetics*; D017630:Connexins / Q000235:genetics*; D017931:DNA Primers / Q000235:genetics; D004455:Echolocation / Q000502:physiology; D019143:Evolution, Molecular; D005136:Eye Proteins / Q000235:genetics*; D016013:Likelihood Functions; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D011544:Pseudogenes / Q000235:genetics; D012177:Retinol-Binding Proteins / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D014796:Visual Perception / Q000235:genetics*; D000099214:Retinol-Binding Proteins, Interstitial
chemical_list: D017630:Connexins; D017931:DNA Primers; D005136:Eye Proteins; D012177:Retinol-Binding Proteins; D000099214:Retinol-Binding Proteins, Interstitial