Gene duplications and evolution of the short wavelength-sensitive visual pigments in vertebrates.
When invertebrate rhodopsins were used as the outgroup, the rooted phylogenetic tree of 26 vertebrate visual pigments (VPs) was constructed. These VPs are distinguished into the following four clusters: (1) RH1 cluster consisting of rhodopsins, (2) RH2 cluster consisting of VPs with variable ranges of absorption spectra, (3) SWS cluster of short wavelength-sensitive VPs, and (4) LWS/MSW cluster of long and medium wavelength-sensitive VPs. Short wavelength-sensitive VPs from Astyanax fasciatus (AF23), goldfish (BCa), chicken (BCg and VGg), and human (BHs) belong to SWS cluster, whereas that from gecko (BGge) belongs to the RH2 cluster. The SWS cluster is further divided into SWS-I (BHs and VGg) and SWS-II (AF23, BCa, and BGg) groups. The SWS-I group has accumulated more amino acid changes than any other group of VPs. It is suggested that amino acid changes at a few key positions might have been important in the functional differentiation of the SWS-I group from the SWS-II group.
Yokoyama
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Department of Biology, Syracuse University, New York 13214.
D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D017124:Conserved Sequence; D006801:Humans; D008027:Light; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D012168:Retinal Pigments / Q000235:genetics* / Q000528:radiation effects; D017386:Sequence Homology, Amino Acid; D014714:Vertebrates / Q000235:genetics*
D012168:Retinal Pigments