In vivo investigation of a new type of rhodopsin photoreceptors from lower plants

Project Information

Grant agreement ID: INTAS-RFBR95-1134

Start date

End date

Funded under

• International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993-

Total cost No data

EU contribution No data

Coordinated by

Universität Regensburg
Germany

Objective

Photosensory transduction in green flagellated algae (Chlamydomonas and related species) is mediated by a photoreceptor protein similar to animal visual pigments. This is the only example of rhodopsin-type proteins found in plants so far, yet not available for in vitro characterization.

In the proposed research project properties of this pigment and molecular mechanisms of photosensory transduction in Chlamydomonas will be studied in vivo by registration of the rhodopsin-mediated photoelectric responses originally described by the authors. Two experimental techniques of photoelectric measurements developed by the authors will be used in parallel studies.

Both methods (suction-pipette technique of microelectrode recording and registration of the photocurrents from cell suspensions) will be further developed to facilitate measurements in "blind" mutants of Chlamydomonas reinhardtii reconstituted with exogenous retinoid compounds.

Electrophysiological studies will be undertaken in conjunction with genetic research. New strains of "blind" mutants will be produced by genetic crossing to promote application of the suction-pipette technique of photoelectric measurements.
In order to achieve single-channel recording of the photoreceptor current, experimental procedures for formation of giga-ohm seals between the cell membrane and glass of the pipette will be developed. Artificial retinoid compounds with modified structure will be synthesized and their effect on the photocurrents in reconstituted Chlamydomonas cells will be investigated.

The expected results of reconsitution studies in "blind" mutants will provide information on the cycle of photochemical conversions of the photoreceptor rhodopsin from Chlamydomonas and on mechanisms of coupling the pigment excitation to generation of electric responses in the cell membrane and will be presented in form of scientific publications. These data will contribute to understanding of basic principles and general evolution of photosensory systems in living organisms.

Programme(s)

• IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993-

Topic(s)

• 4 - Life Sciences

Call for proposal

Data not available

Funding Scheme

Data not available

Coordinator

Universität Regensburg

• EU contribution: No data
• Address: 93040 Regensburg ; Germany
• Total cost: No data

Participants (1)

Moscow State University ' M.V. Lomonosov '

Russia

• EU contribution: No data
• Address: 119899 Moscow
• Total cost: No data