Probing visual transduction in a plant cell: Optical recording of rhodopsin-induced structural changes from Chlamydomonas reinhardtii.

  title={Probing visual transduction in a plant cell: Optical recording of rhodopsin-induced structural changes from Chlamydomonas reinhardtii.},
  author={Rainer Uhl and Peter Hegemann},
  journal={Biophysical journal},
  volume={58 5},
Light scattering studies of vertebrate rod cells have greatly aided our understanding of the visual transduction process. This technique has now been successfully applied to study visual transduction in a unicellular alga. Flash-induced light scattering changes have been recorded which are repeatable, graded with photon exposure, and adaptive. They appear on a timescale of 15-1,000 ms and correlate kinetically with flash-induced movement responses. The responsible photoreceptor is a rhodopsin… Expand
In vitro identification of rhodopsin in the green alga Chlamydomonas.
The in vitro identification of endogenous retinal and a rhodopsin in Chlamydomonas cell extracts and purified membrane preparations is reported and it is concluded that this protein is the visual photoreceptor inChlamyDomonas. Expand
Chlamyrhodopsin represents a new type of sensory photoreceptor.
An improved strategy for the preparation of eyespot membranes containing a retinal binding protein, which reveals that chlamyopsin is not a typical seven helix receptor and shows some homology to invertebrate opsins but not to opsins from halobacteria. Expand
The Photoreceptor Current of the Green Alga Chlamydomonas
Several lines of evidences suggest that these photocurrents are the link between light absorption and alteration of the flagellar beating during a movement response. Expand
Rhodopsin-regulated calcium currents in Chlamydomonas
It is shown by ion current measurements that there are two distinct light-regulated inward currents which are localized in the eyespot and in the flagellar region of the cell and are part of the rhodopsin-regulated signal transduction chain controlling the cellular behaviour in light. Expand
Photophobic responses and phototaxis in Chlamydomonas are triggered by a single rhodopsin photoreceptor
The physiological, electrophysiological and biochemical experiments suggest that all behavioural responses are triggered by a single rhodopsin‐type receptor. Expand
Chapter 8 Algal eyes and their rhodopsin photoreceptors
Algal opsins and their genes show striking homologies to the animal counterparts, and the identification of proteins contributing to this signaling system just begun with the isolation and cloning of opsins from Chlamydomonas and Volvox. Expand
Channelrhodopsin-1: A Light-Gated Proton Channel in Green Algae
A complementary DNA sequence in the green alga Chlamydomonas reinhardtiithat encodes a microbial opsin-related protein, which is suggested to be Channelopsin-1, which shows homology to the light-activated proton pump bacteriorhodopsin. Expand
Photoreception in Chlamydomonas
When the unicellular photosynthetic alga Chlamydomonas is faced with changes in direction, wavelength or intensity of the ambient light, it exhibits distinct behavioral responses, which are directionExpand
Cell biology of phototaxis in flagellate algae
Different criteria can be applied for grouping the photoreceptive organelles of flagellate algae, such as ultrastructural characteristics, the used photoreceptor pigment, the mechanisms involved in primary signal amplification, and extension to low light intensities. Expand
Vision in microalgae
Elucidation of photoreception in flagellated algae will provide deeper insight into the development of visual systems, starting from single-celled organisms and moving up through higher animals. Expand


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