Cited by 75Photoreceptor and optogenetics researchProtein Structure and DynamicsHeat shock proteins research

Homologues of archaeal rhodopsins in plants, animals and fungi: structural and functional predications for a putative fungal chaperone protein

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Zhai, Yufeng, Heijne, Wilbert H.M, Smith, Douglas W, Saier, Milton H·2001·Biochimica et Biophysica Acta (BBA) - Biomembranes

Abstract

The microbial rhodopsins (MR) are homologous to putative chaperone and retinal-binding proteins of fungi. These proteins comprise a coherent family that we have termed the MR family. We have used modeling techniques to predict the structure of one of the putative yeast chaperone proteins, YRO2, based on homology with bacteriorhodopsins (BR). Availability of the structure allowed depiction of conserved residues that are likely to be of functional significance. The results lead us to predict an extracellular protein folding function and a transmembrane proton transport pathway. We suggest that protein folding is energized by a novel mechanism involving the proton motive force. We further show that MR family proteins are distantly related to a family of fungal, animal and plant proteins that include the human lysosomal cystine transporter (LCT) of man (cystinosin), mutations in which cause cystinosis. Sequence and phylogenetic analyses of both the MR family and the LCT family are reported. Proteins in both families are of the same approximate size, exhibit seven putative transmembrane alpha-helical spanners (TMSs) and show limited sequence similarity. We show that the LCT family arose by an internal gene duplication event and that TMSs 1-3 are homologous to TMSs 5-7. Although the same could not be demonstrated statistically for MR family members, homology with the LCT family suggests (but does not prove) a common evolutionary pathway. Thus, TMSs 1-3 and 5-7 in both LCT and MR family members may share a common origin, accounting for their shared structural features.

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  • In bacteria, opsins act as pumps for cations and anions.

    “in bacteria they function as cation and anion pumps,217−223”

    From Chemistry of the Retinoid (Visual) Cycle (2014) · cites this paper as [218]

    The Introduction (page not available) describes proton-translocating bacteriorhodopsins and chloride-translocating halorhodopsins, supporting the cation- and anion-pump functions. But it identifies these as archaeal rhodopsins, not opsins functioning as both types of pump in bacteria. (LLM, conf=0.86)

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Authors
Zhai, Y., Heijne, W. H. M., Smith, D. W., & Saier, M. H.
Affiliations
University of California San Diego (US)
Corresponding author
Saier, Milton H
Venue
Biochimica et Biophysica Acta (BBA) - Biomembranes
Publisher
Elsevier BV
Published
2001-04
Volume
1511
Issue
2
Pages
206-223
ISSN
0005-2736 (ISSN-L)
OpenAlex
W2026016918
Cited by
75
References
61
Citations by year
2025: 1 · 2023: 8 · 2021: 2 · 2020: 3 · 2019: 2 · 2016: 3 · 2015: 6 · 2014: 4 · 2013: 4 · 2012: 4
FWCI
0.51
Type
journal article
Language
en
Open access
Locations
  • Biochimica et Biophysica Acta (BBA) - Biomembranes (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institutes of Health (5r01ai021702-09)
  • U.S. Public Health Service
  • National Institute of General Medical Sciences (9 RO1 GM55434, GM55434, R01GM055434)
  • National Institute of Allergy and Infectious Diseases (5RO1 AI21702)
Topics
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Photoreceptor and optogenetics research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Protein Structure and Dynamics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Heat shock proteins research
Keywords
microbial rhodopsins, bacteriorhodopsin, retinal-binding proteins, protein folding, proton motive force, cystinosin, cystinosis, gene duplication, phylogenetic analysis, homology modeling
MeSH terms
Amino Acid Sequence, Animals, Bacteriorhodopsins, Fungal Proteins, Humans, Models, Molecular, Molecular Sequence Data, Plant Proteins, Rhodopsin, Sequence Alignment, Conserved Sequence, Sequence Homology, Amino Acid, Molecular Chaperones, Evolution, Molecular, Archaeal Proteins

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