Mutated channelrhodopsins with increased sodium and calcium permeability
Please always quote using this URN: urn:nbn:de:bvb:20-opus-197435
- (1) Background: After the discovery and application of Chlamydomonas reinhardtii channelrhodopsins, the optogenetic toolbox has been greatly expanded with engineered and newly discovered natural channelrhodopsins. However, channelrhodopsins of higher Ca\(^{2+}\) conductance or more specific ion permeability are in demand. (2) Methods: In this study, we mutated the conserved aspartate of the transmembrane helix 4 (TM4) within Chronos and PsChR and compared them with published ChR2 aspartate mutants. (3) Results: We found that the ChR2 D156H(1) Background: After the discovery and application of Chlamydomonas reinhardtii channelrhodopsins, the optogenetic toolbox has been greatly expanded with engineered and newly discovered natural channelrhodopsins. However, channelrhodopsins of higher Ca\(^{2+}\) conductance or more specific ion permeability are in demand. (2) Methods: In this study, we mutated the conserved aspartate of the transmembrane helix 4 (TM4) within Chronos and PsChR and compared them with published ChR2 aspartate mutants. (3) Results: We found that the ChR2 D156H mutant (XXM) showed enhanced Na\(^+\) and Ca\(^{2+}\) conductance, which was not noticed before, while the D156C mutation (XXL) influenced the Na\(^+\) and Ca\(^{2+}\) conductance only slightly. The aspartate to histidine and cysteine mutations of Chronos and PsChR also influenced their photocurrent, ion permeability, kinetics, and light sensitivity. Most interestingly, PsChR D139H showed a much-improved photocurrent, compared to wild type, and even higher Na+ selectivity to H\(^+\) than XXM. PsChR D139H also showed a strongly enhanced Ca\(^{2+}\) conductance, more than two-fold that of the CatCh. (4) Conclusions: We found that mutating the aspartate of the TM4 influences the ion selectivity of channelrhodopsins. With the large photocurrent and enhanced Na\(^+\) selectivity and Ca\(^{2+}\) conductance, XXM and PsChR D139H are promising powerful optogenetic tools, especially for Ca\(^{2+}\) manipulation.…
Author: | Xiaodong Duan, Georg Nagel, Shiqiang Gao |
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URN: | urn:nbn:de:bvb:20-opus-197435 |
Document Type: | Journal article |
Faculties: | Fakultät für Biologie / Julius-von-Sachs-Institut für Biowissenschaften |
Language: | English |
Parent Title (English): | Applied Sciences |
ISSN: | 2076-3417 |
Year of Completion: | 2019 |
Volume: | 9 |
Issue: | 4 |
Pagenumber: | 664 |
Source: | Applied Sciences 2019, 9(4), 664; https://doi.org/10.3390/app9040664 |
DOI: | https://doi.org/10.3390/app9040664 |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie |
Tag: | DC gate; calcium; channelrhodopsins; optogenetics; sodium |
Release Date: | 2020/03/02 |
Date of first Publication: | 2019/02/15 |
Open-Access-Publikationsfonds / Förderzeitraum 2019 | |
Licence (German): | CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International |