1
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Fujiyabu C, Sato K, Ohuchi H, Yamashita T. Diversification processes of teleost intron-less opsin genes. J Biol Chem 2023:104899. [PMID: 37295773 PMCID: PMC10339062 DOI: 10.1016/j.jbc.2023.104899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 05/31/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023] Open
Abstract
Opsins are universal photosensitive proteins in animals. Vertebrates have a variety of opsin genes for visual and non-visual photoreceptions. Analysis of the gene structures shows that most opsin genes have introns in their coding regions. However, teleosts exceptionally have several intron-less opsin genes which are presumed to have been duplicated by an RNA-based gene duplication mechanism, retroduplication. Among these retrogenes, we focused on the Opn4 (melanopsin) gene responsible for non-image-forming photoreception. Many teleosts have five Opn4 genes including one intron-less gene, which is speculated to have been formed from a parental intron-containing gene in the Actinopterygii. In this study, to reveal the evolutionary history of Opn4 genes, we analyzed them in teleost (zebrafish and medaka) and non-teleost (bichir, sturgeon and gar) fishes. Our synteny analysis suggests that the intron-less Opn4 gene emerged by retroduplication after branching of the bichir lineage. In addition, our biochemical and histochemical analyses showed that, in the teleost lineage, the newly acquired intron-less Opn4 gene became abundantly used without substantial changes of the molecular properties of the Opn4 protein. This stepwise evolutionary model of Opn4 genes is quite similar to that of rhodopsin genes in the Actinopterygii. The unique acquisition of rhodopsin and Opn4 retrogenes would have contributed to the diversification of the opsin gene repertoires in the Actinopterygii and the adaptation of teleosts to various aquatic environments.
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Affiliation(s)
- Chihiro Fujiyabu
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Keita Sato
- Department of Cytology and Histology, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan
| | - Hideyo Ohuchi
- Department of Cytology and Histology, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan
| | - Takahiro Yamashita
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
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2
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Hagen JFD, Roberts NS, Johnston RJ. The evolutionary history and spectral tuning of vertebrate visual opsins. Dev Biol 2023; 493:40-66. [PMID: 36370769 PMCID: PMC9729497 DOI: 10.1016/j.ydbio.2022.10.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 10/27/2022] [Accepted: 10/31/2022] [Indexed: 11/11/2022]
Abstract
Many animals depend on the sense of vision for survival. In eumetazoans, vision requires specialized, light-sensitive cells called photoreceptors. Light reaches the photoreceptors and triggers the excitation of light-detecting proteins called opsins. Here, we describe the story of visual opsin evolution from the ancestral bilaterian to the extant vertebrate lineages. We explain the mechanisms determining color vision of extant vertebrates, focusing on opsin gene losses, duplications, and the expression regulation of vertebrate opsins. We describe the sequence variation both within and between species that has tweaked the sensitivities of opsin proteins towards different wavelengths of light. We provide an extensive resource of wavelength sensitivities and mutations that have diverged light sensitivity in many vertebrate species and predict how these mutations were accumulated in each lineage based on parsimony. We suggest possible natural and sexual selection mechanisms underlying these spectral differences. Understanding how molecular changes allow for functional adaptation of animals to different environments is a major goal in the field, and therefore identifying mutations affecting vision and their relationship to photic selection pressures is imperative. The goal of this review is to provide a comprehensive overview of our current understanding of opsin evolution in vertebrates.
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Affiliation(s)
- Joanna F D Hagen
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA
| | - Natalie S Roberts
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA
| | - Robert J Johnston
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA.
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3
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Chang CH. Correlated Expression of the Opsin Retrogene LWS-R and its Host Gene in Two Poeciliid Fishes. Zool Stud 2022; 61:e16. [PMID: 36330033 PMCID: PMC9579955 DOI: 10.6620/zs.2022.61-16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 02/22/2022] [Indexed: 06/16/2023]
Abstract
The important role of retrogenes in genome evolution and species differentiation is becoming increasingly accepted. One synapomorphy among cyprinodontoid fish is a retrotransposed version of a long-wavelength sensitive (LWS) opsin gene, LWS-R, within an intron of the gephyrin (GPHN) gene. These two genes display opposing orientations. It had been speculated that LWS-R hijacks the cis-regulatory elements of GPHN for transcription, but whether their expression is correlated had remained unclear. Here, in silico predictions identified putative promoters upstream of the translation start site of LWS-R, indicating that its transcription is driven by its own promoter rather than by the GPHN promoter. However, consistent expression ratios of LWS-R:GPHN in the eyeball and brain of fishes indicate that the respective gene transcriptions are correlated. Co-expression is potentially modulated by histone exchange during GPHN transcription. Two isoforms were detected in this study, i.e., intron-free and intron-retaining. Intron-free LWS-R was only expressed in the eyeball of fishes, whereas intron-retaining LWS-R occurred in both eyeball and brain. Expression of vision-associated LWS-R beyond the eyeball supports that it is co-expressed with more ubiquitous GPHN.
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Affiliation(s)
- Chia-Hao Chang
- Department of Science Education, National Taipei University of Education, No.134, Sec.2, Heping E. Rd., Da'an District, Taipei City 10671, Taiwan. E-mail: (Chang)
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4
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Musilova Z, Salzburger W, Cortesi F. The Visual Opsin Gene Repertoires of Teleost Fishes: Evolution, Ecology, and Function. Annu Rev Cell Dev Biol 2021; 37:441-468. [PMID: 34351785 DOI: 10.1146/annurev-cellbio-120219-024915] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Visual opsin genes expressed in the rod and cone photoreceptor cells of the retina are core components of the visual sensory system of vertebrates. Here, we provide an overview of the dynamic evolution of visual opsin genes in the most species-rich group of vertebrates, teleost fishes. The examination of the rich genomic resources now available for this group reveals that fish genomes contain more copies of visual opsin genes than are present in the genomes of amphibians, reptiles, birds, and mammals. The expansion of opsin genes in fishes is due primarily to a combination of ancestral and lineage-specific gene duplications. Following their duplication, the visual opsin genes of fishes repeatedly diversified at the same key spectral-tuning sites, generating arrays of visual pigments sensitive from the ultraviolet to the red spectrum of the light. Species-specific opsin gene repertoires correlate strongly with underwater light habitats, ecology, and color-based sexual selection. Expected final online publication date for the Annual Review of Cell and Developmental Biology, Volume 37 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Zuzana Musilova
- Department of Zoology, Charles University, Prague 128 44, Czech Republic;
| | | | - Fabio Cortesi
- Queensland Brain Institute, The University of Queensland, Brisbane 4072, Queensland, Australia;
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5
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Escobar-Camacho D, Carleton KL, Narain DW, Pierotti MER. Visual pigment evolution in Characiformes: The dynamic interplay of teleost whole-genome duplication, surviving opsins and spectral tuning. Mol Ecol 2020; 29:2234-2253. [PMID: 32421918 DOI: 10.1111/mec.15474] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 05/09/2020] [Accepted: 05/11/2020] [Indexed: 01/06/2023]
Abstract
Vision represents an excellent model for studying adaptation, given the genotype-to-phenotype map that has been characterized in a number of taxa. Fish possess a diverse range of visual sensitivities and adaptations to underwater light, making them an excellent group to study visual system evolution. In particular, some speciose but understudied lineages can provide a unique opportunity to better understand aspects of visual system evolution such as opsin gene duplication and neofunctionalization. In this study, we showcase the visual system evolution of neotropical Characiformes and the spectral tuning mechanisms they exhibit to modulate their visual sensitivities. Such mechanisms include gene duplications and losses, gene conversion, opsin amino acid sequence and expression variation, and A1 /A2 -chromophore shifts. The Characiforms we studied utilize three cone opsin classes (SWS2, RH2, LWS) and a rod opsin (RH1). However, the characiform's entire opsin gene repertoire is a product of dynamic evolution by opsin gene loss (SWS1, RH2) and duplication (LWS, RH1). The LWS- and RH1-duplicates originated from a teleost specific whole-genome duplication as well as characiform-specific duplication events. Both LWS-opsins exhibit gene conversion and, through substitutions in key tuning sites, one of the LWS-paralogues has acquired spectral sensitivity to green light. These sequence changes suggest reversion and parallel evolution of key tuning sites. Furthermore, characiforms' colour vision is based on the expression of both LWS-paralogues and SWS2. Finally, we found interspecific and intraspecific variation in A1 /A2 -chromophores proportions, correlating with the light environment. These multiple mechanisms may be a result of the diverse visual environments where Characiformes have evolved.
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Affiliation(s)
| | - Karen L Carleton
- Department of Biology, University of Maryland, College Park, MD, USA
| | - Devika W Narain
- Environmental Sciences, Anton de Kom University of Suriname, Paramaribo, Suriname
| | - Michele E R Pierotti
- Naos Marine Laboratories, Smithsonian Tropical Research Institute, Panama, Republic of Panama
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6
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Adrian-Kalchhauser I, Blomberg A, Larsson T, Musilova Z, Peart CR, Pippel M, Solbakken MH, Suurväli J, Walser JC, Wilson JY, Alm Rosenblad M, Burguera D, Gutnik S, Michiels N, Töpel M, Pankov K, Schloissnig S, Winkler S. The round goby genome provides insights into mechanisms that may facilitate biological invasions. BMC Biol 2020; 18:11. [PMID: 31992286 PMCID: PMC6988351 DOI: 10.1186/s12915-019-0731-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 12/13/2019] [Indexed: 12/12/2022] Open
Abstract
Background The invasive benthic round goby (Neogobius melanostomus) is the most successful temperate invasive fish and has spread in aquatic ecosystems on both sides of the Atlantic. Invasive species constitute powerful in situ experimental systems to study fast adaptation and directional selection on short ecological timescales and present promising case studies to understand factors involved the impressive ability of some species to colonize novel environments. We seize the unique opportunity presented by the round goby invasion to study genomic substrates potentially involved in colonization success. Results We report a highly contiguous long-read-based genome and analyze gene families that we hypothesize to relate to the ability of these fish to deal with novel environments. The analyses provide novel insights from the large evolutionary scale to the small species-specific scale. We describe expansions in specific cytochrome P450 enzymes, a remarkably diverse innate immune system, an ancient duplication in red light vision accompanied by red skin fluorescence, evolutionary patterns of epigenetic regulators, and the presence of osmoregulatory genes that may have contributed to the round goby’s capacity to invade cold and salty waters. A recurring theme across all analyzed gene families is gene expansions. Conclusions The expanded innate immune system of round goby may potentially contribute to its ability to colonize novel areas. Since other gene families also feature copy number expansions in the round goby, and since other Gobiidae also feature fascinating environmental adaptations and are excellent colonizers, further long-read genome approaches across the goby family may reveal whether gene copy number expansions are more generally related to the ability to conquer new habitats in Gobiidae or in fish. Electronic supplementary material The online version of this article (10.1186/s12915-019-0731-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Irene Adrian-Kalchhauser
- Program Man-Society-Environment, Department of Environmental Sciences, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland. .,University of Bern, Institute for Fish and Wildlife Health, Länggassstrasse 122, 3012, Bern, Austria.
| | - Anders Blomberg
- Department of Chemistry and Molecular Biology, University of Gothenburg, Medicinaregatan 9C, 41390, Gothenburg, Sweden
| | - Tomas Larsson
- Department of Marine Sciences, University of Gothenburg, Medicinaregatan 9C, 41390, Gothenburg, Sweden
| | - Zuzana Musilova
- Department of Zoology, Charles University, Vinicna 7, 12844, Prague, Czech Republic
| | - Claire R Peart
- Division of Evolutionary Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, 82152 Planegg-, Martinsried, Germany
| | - Martin Pippel
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307, Dresden, Germany
| | - Monica Hongroe Solbakken
- Centre for Ecological and Evolutionary Synthesis, University of Oslo, Blindernveien 31, 0371, Oslo, Norway
| | - Jaanus Suurväli
- Institute for Genetics, University of Cologne, Zülpicher Strasse 47a, 50674, Köln, Germany
| | - Jean-Claude Walser
- Genetic Diversity Centre, ETH, Universitätsstrasse 16, 8092, Zurich, Switzerland
| | - Joanna Yvonne Wilson
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada
| | - Magnus Alm Rosenblad
- Department of Chemistry and Molecular Biology, University of Gothenburg, Medicinaregatan 9C, 41390, Gothenburg, Sweden.,NBIS Bioinformatics Infrastructure for Life Sciences, University of Gothenburg, Medicinaregatan 9C, 41390, Gothenburg, Sweden
| | - Demian Burguera
- Department of Zoology, Charles University, Vinicna 7, 12844, Prague, Czech Republic
| | - Silvia Gutnik
- Biocenter, University of Basel, Klingelbergstrasse 50/70, 4056, Basel, Switzerland
| | - Nico Michiels
- Institute of Evolution and Ecology, University of Tuebingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Mats Töpel
- University of Bern, Institute for Fish and Wildlife Health, Länggassstrasse 122, 3012, Bern, Austria
| | - Kirill Pankov
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada
| | - Siegfried Schloissnig
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria
| | - Sylke Winkler
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307, Dresden, Germany
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7
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Vasconcelos FTGRD, Naman MJV, Hauzman E, Baron J, Fix Ventura D, Bonci DMO. LWS visual pigment in owls: Spectral tuning inferred by genetics. Vision Res 2019; 165:90-97. [DOI: 10.1016/j.visres.2019.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 09/30/2019] [Accepted: 10/03/2019] [Indexed: 11/30/2022]
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8
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Liu DW, Wang FY, Lin JJ, Thompson A, Lu Y, Vo D, Yan HY, Zakon H. The Cone Opsin Repertoire of Osteoglossomorph Fishes: Gene Loss in Mormyrid Electric Fish and a Long Wavelength-Sensitive Cone Opsin That Survived 3R. Mol Biol Evol 2019; 36:447-457. [PMID: 30590689 DOI: 10.1093/molbev/msy241] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Vertebrates have four classes of cone opsin genes derived from two rounds of genome duplication. These are short wavelength sensitive 1(SWS1), short wavelength sensitive 2(SWS2), medium wavelength sensitive (RH2), and long wavelength sensitive (LWS). Teleosts had another genome duplication at their origin and it is believed that only one of each cone opsin survived the ancestral teleost duplication event. We tested this by examining the retinal cones of a basal teleost group, the osteoglossomorphs. Surprisingly, this lineage has lost the typical vertebrate green-sensitive RH2 opsin gene and, instead, has a duplicate of the LWS opsin that is green sensitive. This parallels the situation in mammalian evolution in which the RH2 opsin gene was lost in basal mammals and a green-sensitive opsin re-evolved in Old World, and independently in some New World, primates from an LWS opsin gene. Another group of fish, the characins, possess green-sensitive LWS cones. Phylogenetic analysis shows that the evolution of green-sensitive LWS opsins in these two teleost groups derives from a common ancestral LWS opsin that acquired green sensitivity. Additionally, the nocturnally active African weakly electric fish (Mormyroideae), which are osteoglossomorphs, show a loss of the SWS1 opsin gene. In comparison with the independently evolved nocturnally active South American weakly electric fish (Gymnotiformes) with a functionally monochromatic LWS opsin cone retina, the presence of SWS2, LWS, and LWS2 cone opsins in mormyrids suggests the possibility of color vision.
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Affiliation(s)
- Da-Wei Liu
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan, Miaoli, Taiwan
| | - Feng-Yu Wang
- Taiwan Ocean Research Institute, National Applied Research Laboratories, Kaohsiung, Taiwan
| | - Jinn-Jy Lin
- Biodiversity Research Center, Academia Sinica, Nankang, Taipei, Taiwan
| | - Ammon Thompson
- Department of Integrative Biology, The University of Texas, Austin, TX
| | - Ying Lu
- Department of Integrative Biology, The University of Texas, Austin, TX.,Department of Neuroscience, The University of Texas, Austin, TX
| | - Derek Vo
- Department of Integrative Biology, The University of Texas, Austin, TX
| | - Hong Young Yan
- National Museum of Marine Biology and Aquarium, Chencheng, Pingtung, Taiwan
| | - Harold Zakon
- Department of Integrative Biology, The University of Texas, Austin, TX.,Department of Neuroscience, The University of Texas, Austin, TX
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9
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Schweikert LE, Fitak RR, Caves EM, Sutton TT, Johnsen S. Spectral sensitivity in ray-finned fishes: diversity, ecology and shared descent. ACTA ACUST UNITED AC 2018; 221:jeb.189761. [PMID: 30322978 DOI: 10.1242/jeb.189761] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 10/07/2018] [Indexed: 01/01/2023]
Abstract
A major goal of sensory ecology is to identify factors that underlie sensory-trait variation. One open question centers on why fishes show the greatest diversity among vertebrates in their capacity to detect color (i.e. spectral sensitivity). Over the past several decades, λmax values (photoreceptor class peak sensitivity) and chromacy (photoreceptor class number) have been cataloged for hundreds of fish species, yet the ecological basis of this diversity and the functional significance of high chromacy levels (e.g. tetra- and pentachromacy) remain unclear. In this study, we examined phylogenetic, physiological and ecological patterns of spectral sensitivity of ray-finned fishes (Actinoptergyii) via a meta-analysis of data compiled from 213 species. Across the fishes sampled, our results indicate that trichromacy is most common, ultraviolet λmax values are not found in monochromatic or dichromatic species, and increasing chromacy, including from tetra- to pentachromacy, significantly increases spectral sensitivity range. In an ecological analysis, multivariate phylogenetic latent liability modeling was performed to analyze correlations between chromacy and five hypothesized predictors (depth, habitat, diet, body coloration, body size). In a model not accounting for phylogenetic relatedness, each predictor with the exception of habitat significantly correlated with chromacy: a positive relationship in body color and negative relationships with body size, diet and depth. However, after phylogenetic correction, the only remaining correlated predictor was depth. The findings of this study indicate that phyletic heritage and depth are important factors in fish spectral sensitivity and impart caution about excluding phylogenetic comparative methods in studies of sensory trait variation.
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Affiliation(s)
| | - Robert R Fitak
- Biology Department, Duke University, Durham, NC 27708, USA
| | | | - Tracey T Sutton
- Department of Marine and Environmental Sciences, Nova Southeastern University, Dania Beach, FL 33004, USA
| | - Sönke Johnsen
- Biology Department, Duke University, Durham, NC 27708, USA
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10
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Sandkam BA, Joy JB, Watson CT, Breden F. Genomic Environment Impacts Color Vision Evolution in a Family with Visually Based Sexual Selection. Genome Biol Evol 2018; 9:3100-3107. [PMID: 29121209 PMCID: PMC5714168 DOI: 10.1093/gbe/evx228] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2017] [Indexed: 12/14/2022] Open
Abstract
Many models of evolution by sexual selection predict a coevolution of sensory systems and mate preferences, but the genomic architecture (number and arrangement of contributing loci) underlying these characters could constrain this coevolution. Here, we examine how the genomic organization and evolution of the opsin genes (responsible for tuning color vision) can influence the evolutionary trajectory of sexually selected traits across 15 species in the family Poeciliidae, which includes classic systems for studies of color-mediated sexual selection such as guppies, swordtails, and mollies. Although male coloration patterns and the importance of this coloration in female mate choice vary widely within and among genera, sequencing revealed low variability at amino acid sites that tune Long Wavelength-Sensitive (LWS) opsins in this speciose family. Although most opsin genes in these species appear to have evolved along traditional mutation-selection dynamics, we identified high rates of gene conversion between two of the LWS loci (LWS-1 and LWS-3), likely due to the inverted tandem repeat nature of these genes. Yet members of the subgenus Lebistes appear to resist LWS gene conversion. The LWS opsins are responsible for detecting and discriminating red and orange coloration-a key sexually selected trait in members of the subgenus Lebistes. Taken together these results suggest selection is acting against the homogenizing effects of gene conversion to maintain LWS-1/LWS-3 differences within this subgenus.
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Affiliation(s)
- Benjamin A Sandkam
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.,Department of Biology, University of Maryland, Maryland, USA
| | - Jeffrey B Joy
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.,Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Corey T Watson
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.,Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Kentucky, USA
| | - Felix Breden
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
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11
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Genetic and plastic variation in opsin gene expression, light sensitivity, and female response to visual signals in the guppy. Proc Natl Acad Sci U S A 2018; 115:12247-12252. [PMID: 30420507 PMCID: PMC6275514 DOI: 10.1073/pnas.1706730115] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
High diversity in sexual color signaling in animals has attracted considerable and sustained interest from evolution researchers. It has been suggested that variations in visual properties in guppies result in diverse female preference for sexual color signals, leading to genetic variation based on male body colors. Here, we report that opsin expression varies because of allelic differences as well as the different rearing light environments. The variation in opsin expression influences the diversity in visual light sensitivity. Moreover, the expression of multiple opsin genes influences female responsiveness to the luminous orange colors. Consequently, genetic and environmental variation in opsin gene expression could affect female responsiveness and preference for male sexual colors, facilitating male color polymorphisms. According to the sensory drive model, variation in visual properties can lead to diverse female preferences, which in turn results in a range of male nuptial colors by way of sexual selection. However, the cause of variation in visual properties and the mechanism by which variation drives female response to visual signals remain unclear. Here, we demonstrate that both differences in the long-wavelength–sensitive 1 (LWS-1) opsin genotype and the light environment during rearing lead to variation in opsin gene expression. Opsin expression variation affects the visual sensitivity threshold to long wavelengths of light. Moreover, a behavioral assay using digitally modified video images showed that the expression of multiple opsin genes is positively correlated with the female responsiveness to images of males with luminous orange spots. The findings suggest that genetic polymorphisms and light environment in habitats induce variations in opsin gene expression levels. The variations may facilitate variations in visual sensitivity and female responsiveness to male body colors within and among populations.
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12
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Sandkam B, Dalton B, Breden F, Carleton K. Reviewing guppy color vision: integrating the molecular and physiological variation in visual tuning of a classic system for sensory drive. Curr Zool 2018; 64:535-545. [PMID: 30108634 PMCID: PMC6084590 DOI: 10.1093/cz/zoy047] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/02/2018] [Indexed: 12/11/2022] Open
Abstract
Sensory drive predicts coevolution of mate choice signals with the sensory systems detecting those signals. Guppies are a classic model for sensory drive as mate preferences based on coloration differ across individuals and populations. A large body of work has identified variation in color vision, yet we lack a direct tie between how such variation in color vision influences variation in color preference. Here we bring together studies that have investigated guppy vision over the past 40 years to: (1) highlight our current understanding of where variation occurs in the guppy color vision pathway and (2) suggest future avenues of research into sources of visual system variation that could influence guppy color preference. This will allow researchers to design careful studies that couple measures of color preference with measures of visual system variation from the same individual or population. Such studies will finally provide important answers as to what sets the direction and speed of mate preference evolution via sensory drive.
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Affiliation(s)
- Benjamin Sandkam
- Department of Biology, University of Maryland, College Park, College Park, MD, USA
| | - Brian Dalton
- Department of Biology, University of Maryland, College Park, College Park, MD, USA
| | - Felix Breden
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Karen Carleton
- Department of Biology, University of Maryland, College Park, College Park, MD, USA
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13
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Lin JJ, Wang FY, Li WH, Wang TY. The rises and falls of opsin genes in 59 ray-finned fish genomes and their implications for environmental adaptation. Sci Rep 2017; 7:15568. [PMID: 29138475 PMCID: PMC5686071 DOI: 10.1038/s41598-017-15868-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 11/03/2017] [Indexed: 01/25/2023] Open
Abstract
We studied the evolution of opsin genes in 59 ray-finned fish genomes. We identified the opsin genes and adjacent genes (syntenies) in each genome. Then we inferred the changes in gene copy number (N), syntenies, and tuning sites along each phylogenetic branch during evolution. The Exorh (rod opsin) gene has been retained in 56 genomes. Rh1, the intronless rod opsin gene, first emerged in ancestral Actinopterygii, and N increased to 2 by the teleost-specific whole genome duplication, but then decreased to 1 in the ancestor of Neoteleostei fishes. For cone opsin genes, the rhodopsin-like (Rh2) and long-wave-sensitive (LWS) genes showed great variation in N among species, ranging from 0 to 5 and from 0 to 4, respectively. The two short-wave-sensitive genes, SWS1 and SWS2, were lost in 23 and 6 species, respectively. The syntenies involving LWS, SWS2 and Rh2 underwent complex changes, while the evolution of the other opsin gene syntenies was much simpler. Evolutionary adaptation in tuning sites under different living environments was discussed. Our study provides a detailed view of opsin gene gains and losses, synteny changes and tuning site changes during ray-finned fish evolution.
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Affiliation(s)
- Jinn-Jy Lin
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, 30013, Taiwan.,Bioinformatics Program, Taiwan International Graduate Program, Institute of Information Science, Academia Sinica, Nankang, Taipei, 11529, Taiwan.,Biodiversity Research Center, Academia Sinica, Nankang, Taipei, 11529, Taiwan
| | - Feng-Yu Wang
- Taiwan Ocean Research Institute, National Applied Research Laboratories, Kaohsiung, 852, Taiwan
| | - Wen-Hsiung Li
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, 30013, Taiwan. .,Biodiversity Research Center, Academia Sinica, Nankang, Taipei, 11529, Taiwan. .,Department of Ecology and Evolution, University of Chicago, Chicago, 60637, USA.
| | - Tzi-Yuan Wang
- Biodiversity Research Center, Academia Sinica, Nankang, Taipei, 11529, Taiwan.
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14
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Torres-Dowdall J, Pierotti ME, Härer A, Karagic N, Woltering JM, Henning F, Elmer KR, Meyer A. Rapid and Parallel Adaptive Evolution of the Visual System of Neotropical Midas Cichlid Fishes. Mol Biol Evol 2017; 34:2469-2485. [DOI: 10.1093/molbev/msx143] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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15
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Marques DA, Taylor JS, Jones FC, Di Palma F, Kingsley DM, Reimchen TE. Convergent evolution of SWS2 opsin facilitates adaptive radiation of threespine stickleback into different light environments. PLoS Biol 2017; 15:e2001627. [PMID: 28399148 PMCID: PMC5388470 DOI: 10.1371/journal.pbio.2001627] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 03/06/2017] [Indexed: 11/18/2022] Open
Abstract
Repeated adaptation to a new environment often leads to convergent phenotypic changes whose underlying genetic mechanisms are rarely known. Here, we study adaptation of color vision in threespine stickleback during the repeated postglacial colonization of clearwater and blackwater lakes in the Haida Gwaii archipelago. We use whole genomes from 16 clearwater and 12 blackwater populations, and a selection experiment, in which stickleback were transplanted from a blackwater lake into an uninhabited clearwater pond and resampled after 19 y to test for selection on cone opsin genes. Patterns of haplotype homozygosity, genetic diversity, site frequency spectra, and allele-frequency change support a selective sweep centered on the adjacent blue- and red-light sensitive opsins SWS2 and LWS. The haplotype under selection carries seven amino acid changes in SWS2, including two changes known to cause a red-shift in light absorption, and is favored in blackwater lakes but disfavored in the clearwater habitat of the transplant population. Remarkably, the same red-shifting amino acid changes occurred after the duplication of SWS2 198 million years ago, in the ancestor of most spiny-rayed fish. Two distantly related fish species, bluefin killifish and black bream, express these old paralogs divergently in black- and clearwater habitats, while sticklebacks lost one paralog. Our study thus shows that convergent adaptation to the same environment can involve the same genetic changes on very different evolutionary time scales by reevolving lost mutations and reusing them repeatedly from standing genetic variation.
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Affiliation(s)
- David A. Marques
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
- * E-mail:
| | - John S. Taylor
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Felicity C. Jones
- Stanford University School of Medicine, Department of Developmental Biology, Stanford, California, United States of America
- Friedrich Miescher Laboratory of the Max Planck Society, Tübingen, Germany
| | - Federica Di Palma
- Earlham Institute and University of East Anglia, Department of Biological Sciences, Norwich, United Kingdom
| | - David M. Kingsley
- Stanford University School of Medicine, Department of Developmental Biology, Stanford, California, United States of America
| | - Thomas E. Reimchen
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
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16
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Intraspecific geographic variation in rod and cone visual pigment sensitivity of a parrot, Platycercus elegans. Sci Rep 2017; 7:41445. [PMID: 28128324 PMCID: PMC5269728 DOI: 10.1038/srep41445] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 12/20/2016] [Indexed: 12/24/2022] Open
Abstract
Variation in wavelength sensitivity among subspecies is unknown among vertebrates. The parrot Platycercus elegans has extreme plumage variation between subspecies ranging from pale yellow to crimson which, with differences in background colour and light environment between subspecies, makes it a good candidate for the evolution of within-species differences in vision. We report differences in visual pigments between populations of P. elegans from two subspecies, providing the first known support for population and subspecies variation in visual pigments within a vertebrate species; it is also the first instance of intraspecific variation in rod sensitivity within any vertebrate species. Differences in wavelength sensitivity of rods and cones corresponded to geographic differences in plumage colour. Between study populations, visual pigments varied but not oil droplets. Adaptive functions for the visual pigment differences are untested but they could cause divergence in behaviours associated with colour as well as in dim light, and provide insights into the role of senses in divergence and speciation.
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17
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Künstner A, Hoffmann M, Fraser BA, Kottler VA, Sharma E, Weigel D, Dreyer C. The Genome of the Trinidadian Guppy, Poecilia reticulata, and Variation in the Guanapo Population. PLoS One 2016; 11:e0169087. [PMID: 28033408 PMCID: PMC5199103 DOI: 10.1371/journal.pone.0169087] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 12/12/2016] [Indexed: 11/18/2022] Open
Abstract
For over a century, the live bearing guppy, Poecilia reticulata, has been used to study sexual selection as well as local adaptation. Natural guppy populations differ in many traits that are of intuitively adaptive significance such as ornamentation, age at maturity, brood size and body shape. Water depth, light supply, food resources and predation regime shape these traits, and barrier waterfalls often separate contrasting environments in the same river. We have assembled and annotated the genome of an inbred single female from a high-predation site in the Guanapo drainage. The final assembly comprises 731.6 Mb with a scaffold N50 of 5.3 MB. Scaffolds were mapped to linkage groups, placing 95% of the genome assembly on the 22 autosomes and the X-chromosome. To investigate genetic variation in the population used for the genome assembly, we sequenced 10 wild caught male individuals. The identified 5 million SNPs correspond to an average nucleotide diversity (π) of 0.0025. The genome assembly and SNP map provide a rich resource for investigating adaptation to different predation regimes. In addition, comparisons with the genomes of other Poeciliid species, which differ greatly in mechanisms of sex determination and maternal resource allocation, as well as comparisons to other teleost genera can begin to reveal how live bearing evolved in teleost fish.
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Affiliation(s)
- Axel Künstner
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
- Guest Group Evolutionary Genomics, Max Planck Institute for Evolutionary Biology, Plön, Germany
- * E-mail:
| | - Margarete Hoffmann
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Bonnie A. Fraser
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Verena A. Kottler
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Eshita Sharma
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Detlef Weigel
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Christine Dreyer
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
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18
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Kawamura S, Kasagi S, Kasai D, Tezuka A, Shoji A, Takahashi A, Imai H, Kawata M. Spectral sensitivity of guppy visual pigments reconstituted in vitro to resolve association of opsins with cone cell types. Vision Res 2016; 127:67-73. [DOI: 10.1016/j.visres.2016.06.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 06/21/2016] [Accepted: 06/29/2016] [Indexed: 10/21/2022]
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19
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Bloch NI. The evolution of opsins and color vision: connecting genotype to a complex phenotype. ACTA BIOLÓGICA COLOMBIANA 2016. [DOI: 10.15446/abc.v21n3.53907] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Entender la base genética de los rasgos adaptativos es un paso crítico en el estudio de los procesos evolutivos. Para estudiar la conexión entre genotipo y fenotipo es importante definir el fenotipo a diferentes niveles: desde las proteínas que se construyen con base en un gen, hasta las características finales presentes en un organismo. Las opsinas y los fotopigmentos son elementos primordiales de la visión y entender cómo han evolucionado es fundamental en el estudio de la visión en los animales como un caracter derivado de selección natural o sexual. Este artículo se enfoca en este sistema, en el que se pueden conectar genotipo y fenotipo, como ejemplo de fenotipo complejo para ilustrar las dificultades de establecer una relación clara entre genotipo y fenotipo. Adicionalmente, este artículo tiene como objetivo discutir el funcionamiento del sistema de fotorrecepción, con énfasis particular en las aves, con el fin de enumerar varios factores que deben ser tenidos en cuenta para predecir cambios en la visión a partir del estudio de los fotopigmentos. Dado que los modelos basados en la visión de aves son cada vez más usados en diversas áreas de la biología evolutiva tales como: selección de pareja, depredación y camuflaje; se hace relevante entender los fundamentos y limitaciones de estos modelos. Por esta razón, en este artículo discuto los detalles y aspectos prácticos del uso de los modelos de visión existentes para aves, con el fin de facilitar su uso en futuras investigaciones en diversas áreas de evolución.
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20
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Guggiana-Nilo DA, Engert F. Properties of the Visible Light Phototaxis and UV Avoidance Behaviors in the Larval Zebrafish. Front Behav Neurosci 2016; 10:160. [PMID: 27594828 PMCID: PMC4990545 DOI: 10.3389/fnbeh.2016.00160] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 08/05/2016] [Indexed: 11/13/2022] Open
Abstract
For many organisms, color is an essential source of information from visual scenes. The larval zebrafish has the potential to be a model for the study of this topic, given its tetrachromatic retina and high dependence on vision. In this study we took a step toward understanding how the larval zebrafish might use color sensing. To this end, we used a projector-based paradigm to force a choice of a color stimulus at every turn of the larva. The stimuli used spanned most of the larval spectral range, including activation of its Ultraviolet (UV) cone, which has not been described behaviorally before. We found that zebrafish larvae swim toward visible wavelengths (>400 nm) when choosing between them and darkness, as has been reported with white light. However, when presented with UV light and darkness zebrafish show an intensity dependent avoidance behavior. This UV avoidance does not interact cooperatively with phototaxis toward longer wavelengths, but can compete against it in an intensity dependent manner. Finally, we show that the avoidance behavior depends on the presence of eyes with functional UV cones. These findings open future avenues for studying the neural circuits that underlie color sensing in the larval zebrafish.
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Affiliation(s)
- Drago A. Guggiana-Nilo
- Graduate Program in Biophysics, Harvard University, CambridgeMA, USA
- Department of Molecular and Cellular Biology, Harvard University, CambridgeMA, USA
| | - Florian Engert
- Department of Molecular and Cellular Biology, Harvard University, CambridgeMA, USA
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21
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Sandkam BA, Deere-Machemer KA, Johnson AM, Grether GF, Helen Rodd F, Fuller RC. Exploring visual plasticity: dietary carotenoids can change color vision in guppies (Poecilia reticulata). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2016; 202:527-34. [DOI: 10.1007/s00359-016-1097-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 05/14/2016] [Accepted: 05/27/2016] [Indexed: 01/19/2023]
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22
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Lord NP, Plimpton RL, Sharkey CR, Suvorov A, Lelito JP, Willardson BM, Bybee SM. A cure for the blues: opsin duplication and subfunctionalization for short-wavelength sensitivity in jewel beetles (Coleoptera: Buprestidae). BMC Evol Biol 2016; 16:107. [PMID: 27193495 PMCID: PMC4870758 DOI: 10.1186/s12862-016-0674-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/29/2016] [Indexed: 11/12/2022] Open
Abstract
Background Arthropods have received much attention as a model for studying opsin evolution in invertebrates. Yet, relatively few studies have investigated the diversity of opsin proteins that underlie spectral sensitivity of the visual pigments within the diverse beetles (Insecta: Coleoptera). Previous work has demonstrated that beetles appear to lack the short-wavelength-sensitive (SWS) opsin class that typically confers sensitivity to the “blue” region of the light spectrum. However, this is contrary to established physiological data in a number of Coleoptera. To explore potential adaptations at the molecular level that may compensate for the loss of the SWS opsin, we carried out an exploration of the opsin proteins within a group of beetles (Buprestidae) where short-wave sensitivity has been demonstrated. RNA-seq data were generated to identify opsin proteins from nine taxa comprising six buprestid species (including three male/female pairs) across four subfamilies. Structural analyses of recovered opsins were conducted and compared to opsin sequences in other insects across the main opsin classes—ultraviolet, short-wavelength, and long-wavelength. Results All nine buprestids were found to express two opsin copies in each of the ultraviolet and long-wavelength classes, contrary to the single copies recovered in all other molecular studies of adult beetle opsin expression. No SWS opsin class was recovered. Furthermore, the male Agrilus planipennis (emerald ash borer—EAB) expressed a third LWS opsin at low levels that is presumed to be a larval copy. Subsequent homology and structural analyses identified multiple amino acid substitutions in the UVS and LWS copies that could confer short-wavelength sensitivity. Conclusions This work is the first to compare expressed opsin genes against known electrophysiological data that demonstrate multiple peak sensitivities in Coleoptera. We report the first instance of opsin duplication in adult beetles, which occurs in both the UVS and LWS opsin classes. Through structural comparisons of known insect opsins, we suggest that opsin duplication and amino acid variation within the chromophore binding pocket explains sensitivity in the short-wavelength portion of the visible light spectrum in these species. These findings are the first to reveal molecular complexity of the color vision system within beetles. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0674-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nathan P Lord
- Department of Biology, Brigham Young University, 4102 LSB, Provo, UT, 84602, USA.
| | - Rebecca L Plimpton
- Department of Chemistry and Biochemistry, Brigham Young University, C100 BNSN, Provo, UT, 84602, USA
| | - Camilla R Sharkey
- Department of Biology, Brigham Young University, 4102 LSB, Provo, UT, 84602, USA
| | - Anton Suvorov
- Department of Biology, Brigham Young University, 4102 LSB, Provo, UT, 84602, USA
| | - Jonathan P Lelito
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Plant Protection and Quarantine, Emerald Ash Borer Program, 5936 Ford Court Suite 200, Brighton, MI, 48116, USA
| | - Barry M Willardson
- Department of Chemistry and Biochemistry, Brigham Young University, C100 BNSN, Provo, UT, 84602, USA
| | - Seth M Bybee
- Department of Biology, Brigham Young University, 4102 LSB, Provo, UT, 84602, USA
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23
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Sakai Y, Ohtsuki H, Kasagi S, Kawamura S, Kawata M. Effects of light environment during growth on the expression of cone opsin genes and behavioral spectral sensitivities in guppies (Poecilia reticulata). BMC Evol Biol 2016; 16:106. [PMID: 27193604 PMCID: PMC4870739 DOI: 10.1186/s12862-016-0679-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/06/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The visual system is important for animals for mate choice, food acquisition, and predator avoidance. Animals possessing a visual system can sense particular wavelengths of light emanating from objects and their surroundings and perceive their environments by processing information contained in these visual perceptions of light. Visual perception in individuals varies with the absorption spectra of visual pigments and the expression levels of opsin genes, which may be altered according to the light environments. However, which light environments and the mechanism by which they change opsin expression profiles and whether these changes in opsin gene expression can affect light sensitivities are largely unknown. This study determined whether the light environment during growth induced plastic changes in opsin gene expression and behavioral sensitivity to particular wavelengths of light in guppies (Poecilia reticulata). RESULTS Individuals grown under orange light exhibited a higher expression of long wavelength-sensitive (LWS) opsin genes and a higher sensitivity to 600-nm light than those grown under green light. In addition, we confirmed that variations in the expression levels of LWS opsin genes were related to the behavioral sensitivities to long wavelengths of light. CONCLUSIONS The light environment during the growth stage alters the expression levels of LWS opsin genes and behavioral sensitivities to long wavelengths of light in guppies. The plastically enhanced sensitivity to background light due to changes in opsin gene expression can enhance the detection and visibility of predators and foods, thereby affecting survival. Moreover, changes in sensitivities to orange light may lead to changes in the discrimination of orange/red colors of male guppies and might alter female preferences for male color patterns.
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Affiliation(s)
- Yusuke Sakai
- Department of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, 980-8578, Sendai, Japan
| | - Hajime Ohtsuki
- Department of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, 980-8578, Sendai, Japan
| | - Satoshi Kasagi
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, 277-8562, Kashiwa, Japan
| | - Shoji Kawamura
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, 277-8562, Kashiwa, Japan
| | - Masakado Kawata
- Department of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, 980-8578, Sendai, Japan.
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24
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Sandkam BA, Young CM, Breden FMW, Bourne GR, Breden F. Color vision varies more among populations than among species of live-bearing fish from South America. BMC Evol Biol 2015; 15:225. [PMID: 26475579 PMCID: PMC4609137 DOI: 10.1186/s12862-015-0501-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 09/30/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sensory Bias models for the evolution of mate preference place a great emphasis on the role of sensory system variation in mate preferences. However, the extent to which sensory systems vary across- versus within-species remains largely unknown. Here we assessed whether color vision varies in natural locations where guppies (Poecilia reticulata) and their two closest relatives, Poecilia parae and Poecilia picta, occur in extreme sympatry and school together. All three species base mate preferences on male coloration but differ in the colors preferred. RESULTS Measuring opsin gene expression, we found that within sympatric locations these species have similar color vision and that color vision differed more across populations of conspecifics. In addition, all three species differ across populations in the frequency of the same opsin coding polymorphism that influences visual tuning. CONCLUSIONS Together, this shows sensory systems vary considerably across populations and supports the possibility that sensory system variation is involved in population divergence of mate preference.
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Affiliation(s)
- Benjamin A Sandkam
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, BC, Canada.
| | - C Megan Young
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, BC, Canada.
| | - Frances Margaret Walker Breden
- School of Interactive Arts and Technology, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, BC, Canada.
| | - Godfrey R Bourne
- Department of Biology, University of Missouri-St. Louis, 1 University Blvd., 103 Research Building, St. Louis, 63121, MO, USA.
| | - Felix Breden
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, BC, Canada.
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25
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Ehlman SM, Sandkam BA, Breden F, Sih A. Developmental plasticity in vision and behavior may help guppies overcome increased turbidity. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2015; 201:1125-35. [PMID: 26427995 DOI: 10.1007/s00359-015-1041-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 09/17/2015] [Accepted: 09/19/2015] [Indexed: 01/06/2023]
Abstract
Increasing turbidity in streams and rivers near human activity is cause for environmental concern, as the ability of aquatic organisms to use visual information declines. To investigate how some organisms might be able to developmentally compensate for increasing turbidity, we reared guppies (Poecilia reticulata) in either clear or turbid water. We assessed the effects of developmental treatments on adult behavior and aspects of the visual system by testing fish from both developmental treatments in turbid and clear water. We found a strong interactive effect of rearing and assay conditions: fish reared in clear water tended to decrease activity in turbid water, whereas fish reared in turbid water tended to increase activity in turbid water. Guppies from all treatments decreased activity when exposed to a predator. To measure plasticity in the visual system, we quantified treatment differences in opsin gene expression of individuals. We detected a shift from mid-wave-sensitive opsins to long wave-sensitive opsins for guppies reared in turbid water. Since long-wavelength sensitivity is important in motion detection, this shift likely allows guppies to salvage motion-detecting abilities when visual information is obscured in turbid water. Our results demonstrate the importance of developmental plasticity in responses of organisms to rapidly changing environments.
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Affiliation(s)
- Sean M Ehlman
- Department of Environmental Science and Policy, University of California-Davis, One Shields Ave., Davis, CA, 95616, USA. .,Animal Behavior Graduate Group and Center for Population Biology, University of California-Davis, Davis, USA.
| | - Benjamin A Sandkam
- Department of Biological Sciences, Simon Fraser University, 8888 University Dr., Burnaby, BC, V5A 1S6, Canada
| | - Felix Breden
- Department of Biological Sciences, Simon Fraser University, 8888 University Dr., Burnaby, BC, V5A 1S6, Canada
| | - Andrew Sih
- Department of Environmental Science and Policy, University of California-Davis, One Shields Ave., Davis, CA, 95616, USA
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26
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Sandkam B, Young CM, Breden F. Beauty in the eyes of the beholders: colour vision is tuned to mate preference in the Trinidadian guppy (Poecilia reticulata). Mol Ecol 2015; 24:596-609. [PMID: 25556876 DOI: 10.1111/mec.13058] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 12/18/2014] [Accepted: 12/23/2014] [Indexed: 01/14/2023]
Abstract
A broad range of animals use visual signals to assess potential mates, and the theory of sensory exploitation suggests variation in visual systems drives mate preference variation due to sensory bias. Trinidadian guppies (Poecilia reticulata), a classic system for studies of the evolution of female mate choice, provide a unique opportunity to test this theory by looking for covariation in visual tuning, light environment and mate preferences. Female preference co-evolves with male coloration, such that guppy females from 'low-predation' environments have stronger preferences for males with more orange/red coloration than do females from 'high-predation' environments. Here, we show that colour vision also varies across populations, with 'low'-predation guppies investing more of their colour vision to detect red/orange coloration. In independently colonized watersheds, guppies expressed higher levels of both LWS-1 and LWS-3 (the most abundant LWS opsins) in 'low-predation' populations than 'high-predation' populations at a time that corresponds to differences in cone cell abundance. We also observed that the frequency of a coding polymorphism differed between high- and low-predation populations. Together, this shows that the variation underlying preference could be explained by simple changes in expression and coding of opsins, providing important candidate genes to investigate the genetic basis of female preference variation in this model system.
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Affiliation(s)
- Benjamin Sandkam
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada
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27
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Hurtado-Gonzales JL, Loew ER, Uy JAC. Variation in the visual habitat may mediate the maintenance of color polymorphism in a poeciliid fish. PLoS One 2014; 9:e101497. [PMID: 24987856 PMCID: PMC4079317 DOI: 10.1371/journal.pone.0101497] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 06/06/2014] [Indexed: 12/22/2022] Open
Abstract
The conspicuousness of animal signals is influenced by their contrast against the background. As such, signal conspicuousness will tend to vary in nature because habitats are composed of a mosaic of backgrounds. Variation in attractiveness could result in variation in conspecific mate choice and risk of predation, which, in turn, may create opportunities for balancing selection to maintain distinct polymorphisms. We quantified male coloration, the absorbance spectrum of visual pigments and the photic environment of Poecilia parae, a fish species with five distinct male color morphs: a drab (i.e., grey), a striped, and three colorful (i.e., blue, red and yellow) morphs. Then, using physiological models, we assessed how male color patterns can be perceived in their natural visual habitats by conspecific females and a common cichlid predator, Aequidens tetramerus. Our estimates of chromatic and luminance contrasts suggest that the three most colorful morphs were consistently the most conspicuous across all habitats. However, variation in the visual background resulted in variation in which morph was the most conspicuous to females at each locality. Likewise, the most colorful morphs were the most conspicuous morphs to cichlid predators. If females are able to discriminate between conspicuous prospective mates and those preferred males are also more vulnerable to predation, variable visual habitats could influence the direction and strength of natural and sexual selection, thereby allowing for the persistence of color polymorphisms in natural environments.
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Affiliation(s)
| | - Ellis R. Loew
- Department of Biomedical Sciences, Cornell University, Ithaca, New York, United States of America
| | - J. Albert C. Uy
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
- Department of Biology, University of Miami, Coral Gables, Florida, United States of America
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28
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Tezuka A, Kasagi S, van Oosterhout C, McMullan M, Iwasaki WM, Kasai D, Yamamichi M, Innan H, Kawamura S, Kawata M. Divergent selection for opsin gene variation in guppy (Poecilia reticulata) populations of Trinidad and Tobago. Heredity (Edinb) 2014; 113:381-9. [PMID: 24690753 DOI: 10.1038/hdy.2014.35] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 12/03/2013] [Accepted: 02/24/2014] [Indexed: 11/09/2022] Open
Abstract
The guppy is known to exhibit remarkable interindividual variations in spectral sensitivity of middle to long wavelength-sensitive (M/LWS) cone photoreceptor cells. The guppy has four M/LWS-type opsin genes (LWS-1, LWS-2, LWS-3 and LWS-4) that are considered to be responsible for this sensory variation. However, the allelic variation of the opsin genes, particularly in terms of their absorption spectrum, has not been explored in wild populations. Thus, we examined nucleotide variations in the four M/LWS opsin genes as well as blue-sensitive SWS2-B and ultraviolet-sensitive SWS1 opsin genes for comparison and seven non-opsin nuclear loci as reference genes in 10 guppy populations from various light environments in Trinidad and Tobago. For the first time, we discovered a potential spectral variation (180 Ser/Ala) in LWS-1 that differed at an amino acid site known to affect the absorption spectra of opsins. Based on a coalescent simulation of the nucleotide variation of the reference genes, we showed that the interpopulation genetic differentiation of two opsin genes was significantly larger than the neutral expectation. Furthermore, this genetic differentiation was significantly related to differences in dissolved oxygen (DO) level, and it was not explained by the spatial distance between populations. The DO levels are correlated with eutrophication that possibly affects the color of aquatic environments. These results suggest that the population diversity of opsin genes is significantly driven by natural selection and that the guppy could adapt to various light environments through color vision changes.
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Affiliation(s)
- A Tezuka
- Department of Ecology and Evolutionary Biology, Graduate School of Science, Tohoku University, Sendai, Japan
| | - S Kasagi
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan
| | - C van Oosterhout
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | - M McMullan
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | - W M Iwasaki
- Department of Ecology and Evolutionary Biology, Graduate School of Science, Tohoku University, Sendai, Japan
| | - D Kasai
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan
| | - M Yamamichi
- Department of Evolutionary Studies of Biosystems, Graduate University for Advanced Studies (Sokendai), Hayama, Japan
| | - H Innan
- Department of Evolutionary Studies of Biosystems, Graduate University for Advanced Studies (Sokendai), Hayama, Japan
| | - S Kawamura
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan
| | - M Kawata
- Department of Ecology and Evolutionary Biology, Graduate School of Science, Tohoku University, Sendai, Japan
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Martin RA, Riesch R, Heinen-Kay JL, Langerhans RB. EVOLUTION OF MALE COLORATION DURING A POST-PLEISTOCENE RADIATION OF BAHAMAS MOSQUITOFISH (GAMBUSIA HUBBSI). Evolution 2013; 68:397-411. [DOI: 10.1111/evo.12277] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 09/05/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Ryan A. Martin
- Department of Biological Sciences and W. M. Keck Center for Behavioral Biology; North Carolina State University; Raleigh North Carolina 27695
- Current address: Department of Biology; Case Western Reserve University; Cleveland Ohio 44106
| | - Rüdiger Riesch
- Department of Biological Sciences and W. M. Keck Center for Behavioral Biology; North Carolina State University; Raleigh North Carolina 27695
- Current address: Department of Animal and Plant Sciences; University of Sheffield; Sheffield S10 2TN United Kingdom
| | - Justa L. Heinen-Kay
- Department of Biological Sciences and W. M. Keck Center for Behavioral Biology; North Carolina State University; Raleigh North Carolina 27695
| | - R. Brian Langerhans
- Department of Biological Sciences and W. M. Keck Center for Behavioral Biology; North Carolina State University; Raleigh North Carolina 27695
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Sabbah S, Hawryshyn CW. What has driven the evolution of multiple cone classes in visual systems: object contrast enhancement or light flicker elimination? BMC Biol 2013; 11:77. [PMID: 23826998 PMCID: PMC3720213 DOI: 10.1186/1741-7007-11-77] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 06/27/2013] [Indexed: 11/10/2022] Open
Abstract
Background Two competing theories have been advanced to explain the evolution of multiple cone classes in vertebrate eyes. These two theories have important, but different, implications for our understanding of the design and tuning of vertebrate visual systems. The ‘contrast theory’ proposes that multiple cone classes evolved in shallow-water fish to maximize the visual contrast of objects against diverse backgrounds. The competing ‘flicker theory’ states that multiple cone classes evolved to eliminate the light flicker inherent in shallow-water environments through antagonistic neural interactions, thereby enhancing object detection. However, the selective pressures that have driven the evolution of multiple cone classes remain largely obscure. Results We show that two critical assumptions of the flicker theory are violated. We found that the amplitude and temporal frequency of flicker vary over the visible spectrum, precluding its cancellation by simple antagonistic interactions between the output signals of cones. Moreover, we found that the temporal frequency of flicker matches the frequency where sensitivity is maximal in a wide range of fish taxa, suggesting that the flicker may actually enhance the detection of objects. Finally, using modeling of the chromatic contrast between fish pattern and background under flickering illumination, we found that the spectral sensitivity of cones in a cichlid focal species is optimally tuned to maximize the visual contrast between fish pattern and background, instead of to produce a flicker-free visual signal. Conclusions The violation of its two critical assumptions substantially undermines support for the flicker theory as originally formulated. While this alone does not support the contrast theory, comparison of the contrast and flicker theories revealed that the visual system of our focal species was tuned as predicted by the contrast theory rather than by the flicker theory (or by some combination of the two). Thus, these findings challenge key assumptions of the flicker theory, leaving the contrast theory as the most parsimonious and tenable account of the evolution of multiple cone classes.
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Affiliation(s)
- Shai Sabbah
- Department of Biology, Queen's University, Kingston, Ontario K7L 3N6, Canada.
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Evolutionary changes of multiple visual pigment genes in the complete genome of Pacific bluefin tuna. Proc Natl Acad Sci U S A 2013; 110:11061-6. [PMID: 23781100 DOI: 10.1073/pnas.1302051110] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Tunas are migratory fishes in offshore habitats and top predators with unique features. Despite their ecological importance and high market values, the open-ocean lifestyle of tuna, in which effective sensing systems such as color vision are required for capture of prey, has been poorly understood. To elucidate the genetic and evolutionary basis of optic adaptation of tuna, we determined the genome sequence of the Pacific bluefin tuna (Thunnus orientalis), using next-generation sequencing technology. A total of 26,433 protein-coding genes were predicted from 16,802 assembled scaffolds. From these, we identified five common fish visual pigment genes: red-sensitive (middle/long-wavelength sensitive; M/LWS), UV-sensitive (short-wavelength sensitive 1; SWS1), blue-sensitive (SWS2), rhodopsin (RH1), and green-sensitive (RH2) opsin genes. Sequence comparison revealed that tuna's RH1 gene has an amino acid substitution that causes a short-wave shift in the absorption spectrum (i.e., blue shift). Pacific bluefin tuna has at least five RH2 paralogs, the most among studied fishes; four of the proteins encoded may be tuned to blue light at the amino acid level. Moreover, phylogenetic analysis suggested that gene conversions have occurred in each of the SWS2 and RH2 loci in a short period. Thus, Pacific bluefin tuna has undergone evolutionary changes in three genes (RH1, RH2, and SWS2), which may have contributed to detecting blue-green contrast and measuring the distance to prey in the blue-pelagic ocean. These findings provide basic information on behavioral traits of predatory fish and, thereby, could help to improve the technology to culture such fish in captivity for resource management.
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Kang JH, Schartl M, Walter RB, Meyer A. Comprehensive phylogenetic analysis of all species of swordtails and platies (Pisces: Genus Xiphophorus) uncovers a hybrid origin of a swordtail fish, Xiphophorus monticolus, and demonstrates that the sexually selected sword originated in the ancestral lineage of the genus, but was lost again secondarily. BMC Evol Biol 2013; 13:25. [PMID: 23360326 PMCID: PMC3585855 DOI: 10.1186/1471-2148-13-25] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 01/22/2013] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Males in some species of the genus Xiphophorus, small freshwater fishes from Meso-America, have an extended caudal fin, or sword - hence their common name "swordtails". Longer swords are preferred by females from both sworded and - surprisingly also, non-sworded (platyfish) species that belong to the same genus. Swordtails have been studied widely as models in research on sexual selection. Specifically, the pre-existing bias hypothesis was interpreted to best explain the observed bias of females in presumed ancestral lineages of swordless species that show a preference for assumed derived males with swords over their conspecific swordless males. However, many of the phylogenetic relationships within this genus still remained unresolved. Here we construct a comprehensive molecular phylogeny of all 26 known Xiphophorus species, including the four recently described species (X. kallmani, X. mayae, X. mixei and X. monticolus). We use two mitochondrial and six new nuclear markers in an effort to increase the understanding of the evolutionary relationships among the species in this genus. Based on the phylogeny, the evolutionary history and character state evolution of the sword was reconstructed and found to have originated in the common ancestral lineage of the genus Xiphophorus and that it was lost again secondarily. RESULTS We estimated the evolutionary relationships among all known species of the genus Xiphophorus based on the largest set of DNA markers so far. The phylogeny indicates that one of the newly described swordtail species, Xiphophorus monticolus, is likely to have arisen through hybridization since it is placed with the southern platyfish in the mitochondrial phylogeny, but with the southern swordtails in the nuclear phylogeny. Such discordance between these two types of markers is a strong indication for a hybrid origin. Additionally, by using a maximum likelihood approach the possession of the sexually selected sword trait is shown to be the most likely ancestral state for the genus Xiphophorus. Further, we provide a well supported estimation of the phylogenetic relationships between the previously unresolved northern swordtail groups. CONCLUSIONS This comprehensive molecular phylogeny of the entire genus Xiphophorus provides evidence that a second swordtail species, X. monticolus, arose through hybridization. Previously, we demonstrated that X. clemenciae, another southern swordtail species, arose via hybridization. These findings highlight the potential key role of hybridization in the evolution of this genus and suggest the need for further investigations into how hybridization contributes to speciation more generally.
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Affiliation(s)
- Ji Hyoun Kang
- Lehrstuhl für Zoologie und Evolutionsbiologie, Department of Biology, University of Konstanz, Universitätsstraße 10, Konstanz 78457, Germany
- Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Manfred Schartl
- Physiological Chemistry, Biozentrum, University of Würzburg, Am Hubland, Würzburg, 97074, Germany
| | - Ronald B Walter
- Department of Chemistry and Biochemistry, Texas State University-San Marcos, 601 University Dr, San Marcos, TX, 78666, USA
| | - Axel Meyer
- Lehrstuhl für Zoologie und Evolutionsbiologie, Department of Biology, University of Konstanz, Universitätsstraße 10, Konstanz 78457, Germany
- Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
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Sabbah S, Troje NF, Gray SM, Hawryshyn CW. High complexity of aquatic irradiance may have driven the evolution of four-dimensional colour vision in shallow-water fish. J Exp Biol 2013; 216:1670-82. [DOI: 10.1242/jeb.079558] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Summary
Humans use three cone photoreceptor classes for colour vision, yet many birds, reptiles and shallow-water fish are tetrachromatic and use four cone classes. Screening pigments, that narrow the spectrum of photoreceptors in birds and diurnal reptiles, render visual systems with four cone classes more efficient. To date, however, the question of tetrachromacy in shallow-water fish, that, like humans, lack screening pigments, is still unsolved. We raise the possibility that tetrachromacy in fish has evolved in response to higher spectral complexity of underwater light. We compared the dimensionality of colour vision in humans and fish by examining the spectral complexity of the colour-signal reflected from objects into their eyes. Here we show that fish require four to six cone classes to reconstruct the colour-signal of aquatic objects at the accuracy level achieved by humans viewing terrestrial objects. This is because environmental light, which alters the colour-signals, is more complex and contains more spectral fluctuations underwater than on land. We further show that fish cones are better suited than human cones to detect these spectral fluctuations, suggesting that the capability of fish cones to detect high-frequency fluctuations in the colour-signal confers an advantage. Taken together, we propose that tetrachromacy in fish has evolved to enhance the reconstruction of complex colour-signals in shallow aquatic environments. Of course, shallow-water fish might possess less than four cone classes; however, this would come with the inevitable loss in accuracy of signal reconstruction.
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Opsin Evolution in Damselfish: Convergence, Reversal, and Parallel Evolution Across Tuning Sites. J Mol Evol 2012; 75:79-91. [DOI: 10.1007/s00239-012-9525-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Accepted: 10/03/2012] [Indexed: 11/27/2022]
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Sandkam BA, Joy JB, Watson CT, Gonzalez-Bendiksen P, Gabor CR, Breden F. Hybridization leads to sensory repertoire expansion in a gynogenetic fish, the Amazon molly (poecilia formosa): a test of the hybrid-sensory expansion hypothesis. Evolution 2012; 67:120-30. [PMID: 23289566 DOI: 10.1111/j.1558-5646.2012.01779.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Expansions in sensory systems usually require processes such as gene duplication and divergence, and thus evolve slowly. We evaluate a novel mechanism leading to rapid sensory repertoire expansion: hybrid-sensory expansion (HSE). HSE occurs when two species with differently tuned sensory systems form a hybrid, bringing together alleles from each of the parental species. In one generation, a sensory repertoire is created that is the sum of the variance between parental species. The Amazon molly presents a unique opportunity to test the HSE hypothesis in a "frozen" hybrid. We compared opsin sequences of the Amazon molly, Poecilia formosa, to those of the parental species. Both parental species are homozygous at the RH2-1 locus and each of the four long wavelength sensitive loci, while P. formosa possess two different alleles at these loci; one matching each parental allele. Gene expression analysis showed P. formosa use the expanded opsin repertoire that was the result of HSE. Additionally, behavioral tests revealed P. formosa respond to colored stimuli in a manner similar or intermediate to the parental species P. mexicana and P. latipinna. Together these results strongly support the HSE hypothesis. Hybrid-sensory repertoire expansion is likely important in other hybrid species and in other sensory systems.
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Affiliation(s)
- Benjamin A Sandkam
- Department of Biological Sciences, Simon Fraser University, Burnaby BC, V5A 1S6, Canada.
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Rennison DJ, Owens GL, Taylor JS. Opsin gene duplication and divergence in ray-finned fish. Mol Phylogenet Evol 2011; 62:986-1008. [PMID: 22178363 DOI: 10.1016/j.ympev.2011.11.030] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 11/18/2011] [Accepted: 11/21/2011] [Indexed: 11/17/2022]
Abstract
Opsin gene sequences were first reported in the 1980s. The goal of that research was to test the hypothesis that human opsins were members of a single gene family and that variation in human color vision was mediated by mutations in these genes. While the new data supported both hypotheses, the greatest contribution of this work was, arguably, that it provided the data necessary for PCR-based surveys in a diversity of other species. Such studies, and recent whole genome sequencing projects, have uncovered exceptionally large opsin gene repertoires in ray-finned fishes (taxon, Actinopterygii). Guppies and zebrafish, for example, have 10 visual opsin genes each. Here we review the duplication and divergence events that have generated these gene collections. Phylogenetic analyses revealed that large opsin gene repertories in fish have been generated by gene duplication and divergence events that span the age of the ray-finned fishes. Data from whole genome sequencing projects and from large-insert clones show that tandem duplication is the primary mode of opsin gene family expansion in fishes. In some instances gene conversion between tandem duplicates has obscured evolutionary relationships among genes and generated unique key-site haplotypes. We mapped amino acid substitutions at so-called key-sites onto phylogenies and this exposed many examples of convergence. We found that dN/dS values were higher on the branches of our trees that followed gene duplication than on branches that followed speciation events, suggesting that duplication relaxes constraints on opsin sequence evolution. Though the focus of the review is opsin sequence evolution, we also note that there are few clear connections between opsin gene repertoires and variation in spectral environment, morphological traits, or life history traits.
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Affiliation(s)
- Diana J Rennison
- University of Victoria, Department of Biology, Station CSC, Victoria, BC, Canada V8W 3N5
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Rennison DJ, Owens GL, Allison WT, Taylor JS. Intra-retinal variation of opsin gene expression in the guppy (Poecilia reticulata). J Exp Biol 2011; 214:3248-54. [DOI: 10.1242/jeb.057836] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Although behavioural experiments demonstrate that colouration influences mate choice in many species, a complete understanding of this form of signalling requires information about colour vision in the species under investigation. The guppy (Poecilia reticulata) has become a model species for the study of colour-based sexual selection. To investigate the role of opsin gene duplication and divergence in the evolution of colour-based mate choice, we used in situ hybridization to determine where the guppy's nine cone opsins are expressed in the retina. Long wavelength-sensitive (LWS) opsins were more abundant in the dorsal retina than in the ventral retina. One of the middle wavelength-sensitive opsins (RH2-1) exhibited the opposite pattern, while the other middle wavelength-sensitive opsin (RH2-2) and the short wavelength-sensitive opsins (SWS1, SWS2A and SWS2B) were expressed throughout the retina. We also found variation in LWS opsin expression among individuals. These observations suggest that regions of the guppy retina are specialized with respect to wavelength discrimination and/or sensitivity. Intra-retinal variability in opsin expression, which has been observed in several fish species, might be an adaptation to variation in the strength and spectral composition of light entering the eye from above and below. The discovery that opsin expression varies in the guppy retina may motivate new behavioural experiments designed to study its role in mate choice.
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Affiliation(s)
- Diana J. Rennison
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, 2370-6270 University Boulevard, Vancouver, BC, Canada, V6T 1Z4
- Department of Biology, University of Victoria, PO Box 3020, Station CSC, Victoria, BC, Canada, V8W 3N5
| | - Gregory L. Owens
- Department of Biology, University of Victoria, PO Box 3020, Station CSC, Victoria, BC, Canada, V8W 3N5
- Department of Botany and Biodiversity Research Centre, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC, Canada, V6T 1Z4
| | - W. Ted Allison
- Department of Biological Sciences, University of Alberta, CW 405, Biological Sciences Building, Edmonton, AB, Canada, T6G 2E9
| | - John S. Taylor
- Department of Biology, University of Victoria, PO Box 3020, Station CSC, Victoria, BC, Canada, V8W 3N5
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Fuller RC, Claricoates KM. Rapid light-induced shifts in opsin expression: finding new opsins, discerning mechanisms of change, and implications for visual sensitivity. Mol Ecol 2011; 20:3321-35. [PMID: 21749514 DOI: 10.1111/j.1365-294x.2011.05180.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Light-induced shifts in cone frequency and opsin expression occur in many aquatic species. Yet little is known about how quickly animals can alter opsin expression and, thereby, track their visual environments. Similarly, little is known about whether adult animals can alter opsin expression or whether shifts in opsin expression are limited to critical developmental windows. We took adult wild-caught bluefin killifish (Lucania goodei) from three different lighting environments (spring, swamp and variable), placed them under two different lighting treatments (clear vs. tea-stained water) and monitored opsin expression over 4 weeks. We measured opsin expression for five previously described opsins (SWS1, SWS2B, SWS2A, RH2-1 and LWS) as well as RH2-2 which we discovered via 454 sequencing. We used two different metrics of opsin expression. We measured expression of each opsin relative to a housekeeping gene and the proportional expression of each opsin relative to the total pool of opsins. Population and lighting environment had large effects on opsin expression which were present at the earliest time points indicating rapid shifts in expression. The two measures of expression produced radically different patterns. Proportional measures indicated large effects of light on SWS1 expression, whereas relative measures indicated no such effect. Instead, light had large effects on the relative expression of SWS2B, RH2-2, RH2-1 and LWS. We suggest that proportional measures of opsin expression are best for making inferences about colour vision, but that measures relative to a housekeeping gene are better for making conclusions about which opsins are differentially regulated.
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Affiliation(s)
- Rebecca C Fuller
- Department of Animal Biology, School of Integrative Biology, University of Illinois, Champaign, IL 61820, USA.
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Laver CRJ, Taylor JS. RT-qPCR reveals opsin gene upregulation associated with age and sex in guppies (Poecilia reticulata) - a species with color-based sexual selection and 11 visual-opsin genes. BMC Evol Biol 2011; 11:81. [PMID: 21447186 PMCID: PMC3078887 DOI: 10.1186/1471-2148-11-81] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 03/29/2011] [Indexed: 01/13/2023] Open
Abstract
Background PCR-based surveys have shown that guppies (Poecilia reticulata) have an unusually large visual-opsin gene repertoire. This has led to speculation that opsin duplication and divergence has enhanced the evolution of elaborate male coloration because it improves spectral sensitivity and/or discrimination in females. However, this conjecture on evolutionary connections between opsin repertoire, vision, mate choice, and male coloration was generated with little data on gene expression. Here, we used RT-qPCR to survey visual-opsin gene expression in the eyes of males, females, and juveniles in order to further understand color-based sexual selection from the perspective of the visual system. Results Juvenile and adult (male and female) guppies express 10 visual opsins at varying levels in the eye. Two opsin genes in juveniles, SWS2B and RH2-2, accounted for >85% of all visual-opsin transcripts in the eye, excluding RH1. This relative abundance (RA) value dropped to about 65% in adults, as LWS-A180 expression increased from approximately 3% to 20% RA. The juvenile-to-female transition also showed LWS-S180 upregulation from about 1.5% to 7% RA. Finally, we found that expression in guppies' SWS2-LWS gene cluster is negatively correlated with distance from a candidate locus control region (LCR). Conclusions Selective pressures influencing visual-opsin gene expression appear to differ among age and sex. LWS upregulation in females is implicated in augmenting spectral discrimination of male coloration and courtship displays. In males, enhanced discrimination of carotenoid-rich food and possibly rival males are strong candidate selective pressures driving LWS upregulation. These developmental changes in expression suggest that adults possess better wavelength discrimination than juveniles. Opsin expression within the SWS2-LWS gene cluster appears to be regulated, in part, by a common LCR. Finally, by comparing our RT-qPCR data to MSP data, we were able to propose the first opsin-to-λmax assignments for all photoreceptor types in the cone mosaic.
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Watson CT, Gray SM, Hoffmann M, Lubieniecki KP, Joy JB, Sandkam BA, Weigel D, Loew E, Dreyer C, Davidson WS, Breden F. Gene duplication and divergence of long wavelength-sensitive opsin genes in the guppy, Poecilia reticulata. J Mol Evol 2010; 72:240-52. [PMID: 21170644 DOI: 10.1007/s00239-010-9426-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 12/06/2010] [Indexed: 11/30/2022]
Abstract
Female preference for male orange coloration in the genus Poecilia suggests a role for duplicated long wavelength-sensitive (LWS) opsin genes in facilitating behaviors related to mate choice in these species. Previous work has shown that LWS gene duplication in this genus has resulted in expansion of long wavelength visual capacity as determined by microspectrophotometry (MSP). However, the relationship between LWS genomic repertoires and expression of LWS retinal cone classes within a given species is unclear. Our previous study in the related species, Xiphophorus helleri, was the first characterization of the complete LWS opsin genomic repertoire in conjunction with MSP expression data in the family Poeciliidae, and revealed the presence of four LWS loci and two distinct LWS cone classes. In this study we characterized the genomic organization of LWS opsin genes by BAC clone sequencing, and described the full range of cone cell types in the retina of the colorful Cumaná guppy, Poecilia reticulata. In contrast to X. helleri, MSP data from the Cumaná guppy revealed three LWS cone classes. Comparisons of LWS genomic organization described here for Cumaná to that of X. helleri indicate that gene divergence and not duplication was responsible for the evolution of a novel LWS haplotype in the Cumaná guppy. This lineage-specific divergence is likely responsible for a third additional retinal cone class not present in X. helleri, and may have facilitated the strong sexual selection driven by female preference for orange color patterns associated with the genus Poecilia.
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Affiliation(s)
- Corey T Watson
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
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Fuller RC, Noa LA, Strellner RS. Teasing apart the many effects of lighting environment on opsin expression and foraging preference in bluefin killifish. Am Nat 2010; 176:1-13. [PMID: 20497054 DOI: 10.1086/652994] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Coloration and color vision covary with lighting in many taxa. Determining the mechanisms underlying these patterns is difficult because lighting environments can have multiple effects on signaling that occur at multiple timescales. Lighting environments can (1) immediately affect signal propagation and transmission, which determine the radiance spectrum reaching the receiver; (2) induce variation in visual systems via developmental plasticity; and (3) lead to genetic differences in visual systems due to a history of selection in different habitats. We tease apart these effects on pecking preference and examine the relationship between pecking preference and opsin expression. Using killifish from two visually distinct populations (clear vs. tea-stained water), we performed crosses (genetics), raised animals under different lighting conditions (developmental plasticity), and assayed the preference to peck at different-colored dots under different lighting conditions (immediate effects). Pecks are interpreted as foraging preference. Developmental plasticity affected both pecking preference and opsin expression. Lighting environments also had immediate effects on pecking preference, but these depended on the lighting conditions animals experienced during development. Genetic effects were detected in opsin expression, but there were no corresponding effects on pecking preference. Overall, only 3.36% of the variation in pecking preference was accounted for by opsin expression.
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Affiliation(s)
- Rebecca C Fuller
- Department of Animal Biology, School of Integrative Biology, University of Illinois, Champaign, Illinois 61820, USA.
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Female mating preferences, lighting environment, and a test of the sensory bias hypothesis in the bluefin killifish. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2010.03.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Watson CT, Lubieniecki KP, Loew E, Davidson WS, Breden F. Genomic organization of duplicated short wave-sensitive and long wave-sensitive opsin genes in the green swordtail, Xiphophorus helleri. BMC Evol Biol 2010; 10:87. [PMID: 20353595 PMCID: PMC3087554 DOI: 10.1186/1471-2148-10-87] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Accepted: 03/30/2010] [Indexed: 01/10/2023] Open
Abstract
Background Long wave-sensitive (LWS) opsin genes have undergone multiple lineage-specific duplication events throughout the evolution of teleost fishes. LWS repertoire expansions in live-bearing fishes (family Poeciliidae) have equipped multiple species in this family with up to four LWS genes. Given that color vision, especially attraction to orange male coloration, is important to mate choice within poeciliids, LWS opsins have been proposed as candidate genes driving sexual selection in this family. To date the genomic organization of these genes has not been described in the family Poeciliidae, and little is known about the mechanisms regulating the expression of LWS opsins in any teleost. Results Two BAC clones containing the complete genomic repertoire of LWS opsin genes in the green swordtail fish, Xiphophorus helleri, were identified and sequenced. Three of the four LWS loci identified here were linked in a tandem array downstream of two tightly linked short wave-sensitive 2 (SWS2) opsin genes. The fourth LWS opsin gene, containing only a single intron, was not linked to the other three and is the product of a retrotransposition event. Genomic and phylogenetic results demonstrate that the LWS genes described here share a common evolutionary origin with those previously characterized in other poeciliids. Using qualitative RT-PCR and MSP we showed that each of the LWS and SWS2 opsins, as well as three other cone opsin genes and a single rod opsin gene, were expressed in the eyes of adult female and male X. helleri, contributing to six separate classes of adult retinal cone and rod cells with average λmax values of 365 nm, 405 nm, 459 nm, 499 nm, 534 nm and 568 nm. Comparative genomic analysis identified two candidate teleost opsin regulatory regions containing putative CRX binding sites and hormone response elements in upstream sequences of LWS gene regions of seven teleost species, including X. helleri. Conclusions We report the first complete genomic description of LWS and SWS2 genes in poeciliids. These data will serve as a reference for future work seeking to understand the relationship between LWS opsin genomic organization, gene expression, gene family evolution, sexual selection and speciation in this fish family.
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Affiliation(s)
- Corey T Watson
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
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Windsor DJ, Owens GL. The opsin repertoire of Jenynsia onca: a new perspective on gene duplication and divergence in livebearers. BMC Res Notes 2009; 2:159. [PMID: 19656397 PMCID: PMC2732921 DOI: 10.1186/1756-0500-2-159] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 08/05/2009] [Indexed: 11/26/2022] Open
Abstract
Background Jenynsia onca, commonly known as the one sided livebearer, is a member of the family Anablepidae. The opsin gene repertoires of J. onca's close relatives, the four-eyed fish (Anableps anableps) and the guppy (Poecilia reticulata), have been characterized and each found to include one unique LWS opsin. Currently, the relationship among LWS paralogs and orthologs in these species are unclear, making it difficult to test the hypotheses that link vision to morphology or life history traits. The phylogenetic signal appears to have been disrupted by gene conversion. Here we have sequenced the opsin genes of J. onca in order to resolve these relationships. Findings We identified nine visual opsins; LWS S180r, LWS S180, LWS P180, SWS1, SWS2A, SWS2B, RH1, RH2-1, and RH2-2. Key site analysis revealed only one unique haplotype, RH2-2, although this is unlikely to shift λmax significantly. LWS P180 was found to be a product of a gene conversion event with LWS S180, followed by convergence to a proline residue at the 180 site. Conclusion Jenynsia onca has at least 9 visual opsins: three LWS, one RH1, two RH2, one SWS1 and two SWS2. The presence of LWS P180 moves the location of the LWS P180-S180 tandem duplication event back to the base of the Poeciliidae-Anablepidae clade, expanding the number of species possessing this unusual blue shifted LWS opsin. The presence of the LWS P180 gene also confirms that gene conversion events have homogenized opsin paralogs in fish, just as they have in humans.
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Affiliation(s)
- Diana J Windsor
- Department of Biology, University of Victoria, 3800 Finnerty Rd, Victoria, British Columbia, Canada.
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Hofmann CM, Carleton KL. Gene duplication and differential gene expression play an important role in the diversification of visual pigments in fish. Integr Comp Biol 2009; 49:630-43. [DOI: 10.1093/icb/icp079] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Owens GL, Windsor DJ, Mui J, Taylor JS. A fish eye out of water: ten visual opsins in the four-eyed fish, Anableps anableps. PLoS One 2009; 4:e5970. [PMID: 19551143 PMCID: PMC2696081 DOI: 10.1371/journal.pone.0005970] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Accepted: 05/27/2009] [Indexed: 11/30/2022] Open
Abstract
The “four-eyed” fish Anableps anableps has numerous morphological adaptations that enable above and below-water vision. Here, as the first step in our efforts to identify molecular adaptations for aerial and aquatic vision in this species, we describe the A. anableps visual opsin repertoire. We used PCR, cloning, and sequencing to survey cDNA using unique primers designed to amplify eight sequences from five visual opsin gene subfamilies, SWS1, SWS2, RH1, RH2, and LWS. We also used Southern blotting to count opsin loci in genomic DNA digested with EcoR1 and BamH1. Phylogenetic analyses confirmed the identity of all opsin sequences and allowed us to map gene duplication and divergence events onto a tree of teleost fish. Each of the gene-specific primer sets produced an amplicon from cDNA, indicating that A. anableps possessed and expressed at least eight opsin genes. A second PCR-based survey of genomic and cDNA uncovered two additional LWS genes. Thus, A. anableps has at least ten visual opsins and all but one were expressed in the eyes of the single adult surveyed. Among these ten visual opsins, two have key site haplotypes not found in other fish. Of particular interest is the A. anableps-specific opsin in the LWS subfamily, S180γ, with a SHYAA five key site haplotype. Although A. anableps has a visual opsin gene repertoire similar to that found in other fishes in the suborder Cyprinodontoidei, the LWS opsin subfamily has two loci not found in close relatives, including one with a key site haplotype not found in any other fish species. A. anableps opsin sequence data will be used to design in situ probes allowing us to test the hypothesis that opsin gene expression differs in the distinct ventral and dorsal retinas found in this species.
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Affiliation(s)
- Gregory L. Owens
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Diana J. Windsor
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Justin Mui
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - John S. Taylor
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
- * E-mail:
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Davies WL, Collin SP, Hunt DM. Adaptive Gene Loss Reflects Differences in the Visual Ecology of Basal Vertebrates. Mol Biol Evol 2009; 26:1803-9. [DOI: 10.1093/molbev/msp089] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Jones JC, Gunter HM, Meyer A. Will he still look good with the lights on? Spectral tuning of visual pigments in fish. J Biol 2008; 7:26. [PMID: 18828890 PMCID: PMC2776405 DOI: 10.1186/jbiol86] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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