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Convergent spectral shifts to blue-green vision in mammals extends the known sensitivity of vertebrate M/LWS pigments.

ABSTRACT: Daylight vision in most mammals is mediated predominantly by a middle/long wavelength-sensitive (M/LWS) pigment. Although spectral sensitivity and associated shifts in M/LWS are mainly determined by five critical sites, predicted phenotypic variation is rarely validated, and its ecological significance is unclear. We experimentally determine spectral tuning of M/LWS pigments and show that two highly divergent taxa, the gerbil and the elephant-shrew, have undergone independent dramatic blue-green shifts to 490 nm. By generating mutant proteins, we identify additional critical sites contributing to these shifts. Our results, which extend the known range of spectral tuning of vertebrate M/LWS, provide a compelling case of functional convergence, likely related to parallel adaptive shifts from nocturnal to brighter light conditions in similar habitats.

SUBMITTER: Chi H

PROVIDER: S-EPMC7165416 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Convergent spectral shifts to blue-green vision in mammals extends the known sensitivity of vertebrate M/LWS pigments.

Chi Hai H Cui Yimeng Y Rossiter Stephen J SJ Liu Yang Y

Proceedings of the National Academy of Sciences of the United States of America 20200402 15

Daylight vision in most mammals is mediated predominantly by a middle/long wavelength-sensitive (M/LWS) pigment. Although spectral sensitivity and associated shifts in M/LWS are mainly determined by five critical sites, predicted phenotypic variation is rarely validated, and its ecological significance is unclear. We experimentally determine spectral tuning of M/LWS pigments and show that two highly divergent taxa, the gerbil and the elephant-shrew, have undergone independent dramatic blue-green ...[more]

PMID: 32241894

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