Channelrhodopsin-1: A Light-Gated Proton Channel in Green Algae

@article{Nagel2002Channelrhodopsin1AL,
  title={Channelrhodopsin-1: A Light-Gated Proton Channel in Green Algae},
  author={G. Nagel and D. Ollig and M. Fuhrmann and S. Kateriya and A. Musti and E. Bamberg and P. Hegemann},
  journal={Science},
  year={2002},
  volume={296},
  pages={2395 - 2398}
}
Phototaxis and photophobic responses of green algae are mediated by rhodopsins with microbial-type chromophores. We report a complementary DNA sequence in the green alga Chlamydomonas reinhardtiithat encodes a microbial opsin-related protein, which we term Channelopsin-1. The hydrophobic core region of the protein shows homology to the light-activated proton pump bacteriorhodopsin. Expression of Channelopsin-1, or only the hydrophobic core, inXenopus laevis oocytes in the presence of all-trans… Expand
Channelrhodopsins: directly light-gated cation channels.
TLDR
It is suggested that ChRs are involved in phototaxis of green algae and heterologous expression of ChR2 is useful to manipulate intracellular pCa or membrane potential of animal cells, simply by illumination. Expand
Channelrhodopsin-Dependent Photo-Behavioral Responses in the Unicellular Green Alga Chlamydomonas reinhardtii.
TLDR
This chapter introduces C. reinhardtii as an experimental organism and explains the current understanding of how the cell senses light and shows photo-behavioral responses. Expand
New Channelrhodopsin with a Red-Shifted Spectrum and Rapid Kinetics from Mesostigma viride
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Channelrhodopsins that function as phototaxis receptors in flagellate algae have recently come into the spotlight as genetically encoded single-molecule optical switches for turning on neuronal firing or other cellular processes, a technique called “optogenetics,” and MChR1, a promising candidate for optogenetic applications, is identified. Expand
Channelrhodopsin-2, a directly light-gated cation-selective membrane channel
  • G. Nagel, T. Szellas, +6 authors E. Bamberg
  • Biology, Medicine
  • Proceedings of the National Academy of Sciences of the United States of America
  • 2003
TLDR
It is demonstrated by functional expression, both in oocytes of Xenopus laevis and mammalian cells, that ChR2 is a directly light-switched cation-selective ion channel, and may be used to depolarize small or large cells, simply by illumination. Expand
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Light-driven proton pumping in a fungal rhodopsin from Leptosphaeria maculans is demonstrated, implying that in addition to oxidative phosphorylation and chlorophyll photosynthesis, some lower eukaryotes may have retained the archaeal route of building an electrochemical transmembrane gradient of protons. Expand
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Cytoplasmic extensions of the channelrhodopsins 1 and 2 interacts in Chlamydomonas reinhardtii
Unicellular bi-flagellated green alga, Chlamydomonas reinhardtii exhibits two types of photomotility responses (phototaxis and photophobic responses).1,2 These two Photo behavioral responses helpExpand
Lateral Gene Transfer of Anion-Conducting Channelrhodopsins between Green Algae and Giant Viruses
TLDR
The discovery of a new family of phylogenetically distinct ChRs encoded by marine giant viruses and acquired from their unicellular green algal hosts are reported, likely involved in behavioral responses to light. Expand
Structurally Distinct Cation Channelrhodopsins from Cryptophyte Algae.
TLDR
Despite their lack of residues characteristic of the chlorophyte cation channels, these proteins are cation-conducting channelrhodopsins that carry out light-gated passive transport of Na(+) and H(+). Expand
The multitalented microbial sensory rhodopsins.
  • J. Spudich
  • Biology, Medicine
  • Trends in microbiology
  • 2006
TLDR
New work on cyanobacteria, algae, fungi and marine proteobacteria is revealing how evolution has modified the common design of these proteins to produce a remarkably rich diversity in their signaling biochemistry. Expand
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