Extraordinarily low evolutionary rates of short wavelength-sensitive opsin pseudogenes

• Authors: Shozo Yokoyama, Emory University; William T. Starmer, Syracuse University; Yang Liu, Emory University; Takashi Tada, Emory University; Lyle Britt, National Oceanic and Atmospheric Administration
• Journal Title: Генетика / Genetika / Russian Journal of Genetics
• Volume: Volume 534, Number 1
• Publisher: Springer Verlag (Germany) | 2014-01-15, Pages 93-99
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1016/j.gene.2013.09.114
• Subjects: Biology, Genetics; Biology, Molecular
• Keywords: Science & Technology; Life Sciences & Biomedicine; Genetics & Heredity; Aquatic animals; SWS1 pseudogenes; Molecular evolution; DETECTING POSITIVE SELECTION; VISUAL PIGMENTS; MOLECULAR EVOLUTION; ADAPTIVE EVOLUTION; NUCLEOTIDE SUBSTITUTIONS; ASTYANAX-FASCIATUS; GENE-EXPRESSION; MOUSE OOCYTES; COLOR-VISION; DNA-SEQUENCE

Abstract

Aquatic organisms such as cichlids, coelacanths, seals, and cetaceans are active in UV-blue color environments, but many of them mysteriously lost their abilities to detect these colors. The loss of these functions is a consequence of the pseudogenization of their short wavelength-sensitive (SWS1) opsin genes without gene duplication. We show that the SWS1 gene (BdenS1ψ) of the deep-sea fish, pearleye (Benthalbella dentata), became a pseudogene in a similar fashion about 130million years ago (Mya) yet it is still transcribed. The rates of nucleotide substitution (~1.4×10-9/site/year) of the pseudogenes of these aquatic species as well as some prosimian and bat species are much smaller than the previous estimates for the globin and immunoglobulin pseudogenes.