Evidence map›Paper›PMID 33243140›Full record

ArticleBMC evolutionary biology2020

Visual adaptation of opsin genes to the aquatic environment in sea snakes.

Takashi Seiko, Takushi Kishida, Mina Toyama, Takahiko Hariyama, Takashi Okitsu, Akimori Wada, Mamoru Toda, Yoko Satta, Yohey Terai

Open access · goldAbstract read
In one paragraph

Article in BMC evolutionary biology, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
0.5field-weighted citation impact, top 36% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed, 11 citations in OpenAlex.

  1. Article
  2. Article
  3. Why sequence the genome of every species? A view from evolutionary biology.Journal of the Marine Biological Association of the United Kingdom. Marine Biological Association of the United Kingdom · 2025
    Article
  4. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors at 5 institutions in 1 country.

Takashi SeikoDepartment of Evolutionary Studies of Biosystems, SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, Kanagawa, 240-0193, Japan.
Takushi KishidaWildlife Research Center, Kyoto University, 2-24 Tanaka Sekiden-cho, Sakyo, Kyoto, 606-8203, Japan.
Mina ToyamaDepartment of Biology, Faculty of Medicine, Hamamatsu University School of Medicine, Handayama, Hamamatsu, Japan.
Takahiko HariyamaDepartment of Biology, Faculty of Medicine, Hamamatsu University School of Medicine, Handayama, Hamamatsu, Japan.
Takashi OkitsuLaboratory of Organic Chemistry for Life Science, Kobe Pharmaceutical University, 4-19-1, Motoyamakita, Higashinada, Kobe, 658-8558, Japan.
Akimori WadaLaboratory of Organic Chemistry for Life Science, Kobe Pharmaceutical University, 4-19-1, Motoyamakita, Higashinada, Kobe, 658-8558, Japan.
Mamoru TodaTropical Biosphere Research Center, University of the Ryukyus, Nishihara, Okinawa, 903-0213, Japan.
Yoko SattaDepartment of Evolutionary Studies of Biosystems, SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, Kanagawa, 240-0193, Japan.
Yohey TeraiDepartment of Evolutionary Studies of Biosystems, SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, Kanagawa, 240-0193, Japan. terai_yohei@soken.ac.jp.ORCID 0000-0003-3353-3420
The Graduate University for Advanced Studies, SOKENDAI · JPHamamatsu University School of Medicine · JPKobe Pharmaceutical University · JPKyoto University · JPUniversity of the Ryukyus · JP

Funding

Japan Society for the Promotion of Science JP18K06361Japan Society for the Promotion of Science JP19H03289
6 · The paper itself

Abstract

backgroundEvolutionary transitions from terrestrial to aquatic life history cause drastic changes in sensory systems. Indeed, the drastic changes in vision have been reported in many aquatic amniotes, convergently. Recently, the opsin genes of the full-aquatic sea snakes have been reported. However, those of the amphibious sea snakes have not been examined in detail.

resultsHere, we investigated opsin genes and visual pigments of sea snakes. We determined the sequences of SWS1, LWS, and RH1 genes from one terrestrial, three amphibious and four fully-aquatic elapids. Amino acid replacements at four and one spectra-tuning positions were found in LWS and RH1, respectively. We measured or predicted absorption of LWS and RH1 pigments with A1-derived retinal. During their evolution, blue shifts of LWS pigments have occurred stepwise in amphibious sea snakes and convergently in both amphibious and fully-aquatic species.

conclusionsBlue shifted LWS pigments may have adapted to deep water or open water environments dominated by blue light. The evolution of opsins differs between marine mammals (cetaceans and pinnipeds) and sea snakes in two fundamental ways: (1) pseudogenization of opsins in marine mammals; and (2) large blue shifts of LWS pigments in sea snakes. It may be possible to explain these two differences at the level of photoreceptor cell composition given that cone and rod cells both exist in mammals whereas only cone cells exist in fully-aquatic sea snakes. We hypothesize that the differences in photoreceptor cell compositions may have differentially affected the evolution of opsins in divergent amniote lineages.

Indexed as

AnimalsAquatic OrganismsHydrophiidaeOpsinsRetinal Cone Photoreceptor CellsVision, OcularOpsinsAquatic amniotesOpsin genesSea snakesVisual adaptationVisual pigments

Identifiers

PMID33243140
PMCPMC7690139
OpenAlexW3108060584

What OpenQuestion holds

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LicenceCC BY
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.