Identification of the Channelrhodopsin Genes in the Green and Cryptophytic Algae from the White and Black Seas

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Olga V. Karpova^1,a*, Elizaveta N. Vinogradova^1,2, and Elena S. Lobakova¹

¹Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia

²Kurchatov Institute National Research Center, 123182 Moscow, Russia

^* To whom correspondence should be addressed.

Received July 6, 2022; Revised August 24, 2022; Accepted August 24, 2022

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Due to the unique capability of modulating cell membrane potential upon photoactivation, channelrhodopsins of green (Chlorophyta) and cryptophytic (Cryptophyta) algae are widely employed in optogenetics, a modern method of light-dependent regulation of biological processes. To enable the search for new genes perspective for optogenetics, we have developed the PCR tests for the presence of genes of the cation and anion channelrhodopsins. Six isolates of green algae Haematococcus and Bracteacoccus from the White Sea region and 2 specimens of Rhodomonas sp. (Cryptophyta) from the regions of White and Black Seas were analyzed. Using our PCR test we have demonstrated the known Haematococcus rhodopsin genes and have discovered novel rhodopsin genes in the genus of Bracteacoccus. Two distantly homologous genes of anion channelrhodopsins were also identified in the cryptophytic Rhodomonas sp. from the White and Black Seas. These results indicate that the developed PCR tests might be useful tool for a broad-range screening of the Chlorophyta and Cryptophyta algae to identify unique channelrhodopsin genes.

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KEY WORDS: cation channelrhodopsins, anion channelrhodopsins, green algae, cryptophytic algae, optogenetics

DOI: 10.1134/S0006297922100121

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