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Updated: Jul 8, 2025
08:39
Whole-cell Patch-clamp Recordings for Electrophysiological Determination of Ion Selectivity in Channelrhodopsins
Published on: May 22, 2017
17.2K
Retinal-Based Anion Pump from the Cyanobacterium Tolypothrix campylonemoides.
Tatyana I Rokitskaya1, Aleksey A Alekseev2, Fedor M Tsybrov2
1Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia. rokitskaya@belozersky.msu.ru.
Biochemistry. Biokhimiia
|December 17, 2023
Summary
A novel microbial anion transporter, TcaR rhodopsin, was identified and characterized. This protein functions as a powerful anion pump, offering potential applications in optogenetics and membrane protein research.
Area of Science:
- Microbiology
- Biochemistry
- Molecular Biology
Background:
- Rhodopsins are light-activated proteins involved in various cellular functions.
- Microbial rhodopsins, particularly anion pumps, are of interest for their potential applications.
Purpose of the Study:
- To characterize the TcaR rhodopsin from Tolypothrix campylonemoides.
- To investigate its function as an anion transporter.
Main Methods:
- Amino acid sequence analysis of TcaR.
- Expression and purification of TcaR in E. coli.
- Functional assays using proteoliposomes, nanodiscs, planar bilayer lipid membranes (BLMs), and voltage-sensitive dyes.
Main Results:
- TcaR possesses a TSD motif, similar to known halorhodopsins.
- TcaR was successfully expressed, purified, and reconstituted into membranes.
- Functional studies confirmed TcaR operates as a potent anion pump.
Conclusions:
- TcaR rhodopsin is a novel microbial anion transporter with significant functional activity.
- TcaR warrants further investigation for fundamental membrane protein studies and optogenetic applications.
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