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Optogenetic control of plant growth by a microbial rhodopsin


While rhodopsin-based optogenetics has revolutionized neuroscience1,2, poor expression of opsins and the absence of the essential cofactor all-trans-retinal has complicated the application of rhodopsins in plants. Here, we demonstrate retinal production in plants and improved rhodopsin targeting for green light manipulation of plant cells using the Guillardia theta light-gated anion channelrhodopsin GtACR13. Green light induces a massive increase in anion permeability and pronounced membrane potential changes when GtACR1 is expressed, enabling non-invasive manipulation of plant growth and leaf development. Using light-driven anion loss, we could mimic drought conditions and bring about leaf wilting despite sufficient water supply. Expressed in pollen tubes, global GtACR1 activation triggers membrane potential depolarizations due to large anion currents. While global illumination was associated with a reversible growth arrest, local GtACR1 activation at the flanks of the apical dome steers growth direction away from the side with increased anion conductance. These results suggest a crucial role of anion permeability for the guidance of pollen tube tip growth. This plant optogenetic approach could be expanded to create an entire pallet of rhodopsin-based tools4, greatly facilitating dissection of plant ion-signalling pathways.

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Fig. 1: Ret–eYFP-expressing N. tabacum plants produce retinal and show similar growth characteristics to WT plants.
Fig. 2: Functional expression of improved ACR1 2.0 in N. tabacum.
Fig. 3: Optogenetic manipulation of pollen tube growth by ACR1.

Data availability

The source data and DNA sequences of this study are provided as supplementary data files. Source data are provided with this paper.


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This study is funded by the Deutsche Forschungsgemeinschaft (DFG) Projektnummer 374031971 TRR 240 A04 and 417451587. G.N. acknowledges the support provided by the Prix Louis-Jeantet. Financial support by the Deutsche Forschungsgemeinschaft is accredited to K.R.K. (DFG KO3657/2-3). Y.Z., M.D. and X.D. are supported by the Chinese Scholarship Council. We acknowledge A. Reyer for help with plant cell impalement.

Author information

Authors and Affiliations



G.N., S.G., M.K., M.J.M., R.H. and K.R.K. conceived the project. S.G., K.R.K. and G.N. designed and supervised the experiments. Y.Z., M.D., J.Y.-S. and S.G. performed the plant experiments and analysed the data. J.Y.-S. and X.D. performed the Xenopus oocyte experiments. M.K. performed the retinal and carotenoids analysis. J.L. and M.R. performed the leaf cuticular wax analysis. S.G., K.R.K. and G.N. wrote the paper. All authors edited and approved the final version of the manuscript to be published.

Corresponding authors

Correspondence to Shiqiang Gao, Kai R. Konrad or Georg Nagel.

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Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Plants thanks Toshinori Kinoshita, Matias Zurbriggen and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Methods, Figs. 1–8, legends for Videos and DNA sequences used in this study.

Reporting Summary

Supplementary Video 1

Transient expression of RC2–eYFP in pollen tubes. Pollen transiently transformed with RC2–eYFP were pre-incubated in semi-solid pollen germination medium for 5–7 h at room temperature in the dark. Real time is indicated in the top left corner. eYFP fluorescence is indicated by yellow colour. Scale bar, 10 μm.

Supplementary Video 2

Growths of WT, LeLAT52::Ret–eYFP and LeLAT52::Ret–ACR1 2.0 pollen tubes in response to the global illumination. WT, LeLAT52::Ret–eYFP #1 and LeLAT52::Ret–ACR1 2.0 #1 transgenic expressed pollen were pre-incubated in semi-solid pollen germination medium for 5–7 h at room temperature in the dark. Red light was used to perform the bright-field imaging. Pollen tubes growing in 10 min dark, 10 min green light illumination and then 20 min dark were captured. Both WT and Ret–eYFP-expressing pollen tubes showed no response to green light (532 nm, 2 mW mm−2 (9,600 μmol m−2 s−1)) illumination. Global illumination had a negative effect on the growth of Ret–ACR1 2.0-expressing transgenic pollen tubes. Real time (min:s) is indicated in the top left corner.

Supplementary Video 3

Growth of LeLAT52::Ret–ACR1 2.0 #1-1 pollen tubes in response to local illumination.

Supplementary Video 4

Growth of LeLAT52::Ret–ACR1 2.0 #1-2 pollen tubes in response to local illumination.

Supplementary Video 5

Growth of LeLAT52::Ret–ACR1 2.0 #1-3 pollen tubes in response to local illumination.

Supplementary Video 6

Growth of LeLAT52::Ret–ACR1 2.0 #2-1 pollen tubes in response to local illumination.

Supplementary Video 7

Growth of LeLAT52::Ret–ACR1 2.0 #2-2 pollen tubes in response to local illumination.

Supplementary Video 8

Growth of LeLAT52::Ret–ACR1 2.0 #2-3 pollen tubes in response to local illumination.

Supplementary Video 9

Growth of WT pollen tubes in response to local illumination #1.

Supplementary Video 10

Growth of WT pollen tubes in response to local illumination #2.

Supplementary Video 11

Growth of WT pollen tubes in response to local illumination #3.

Source data

Source Data Fig. 1

Statistical source data.

Source Data Fig. 2

Statistical source data.

Source Data Fig. 3

Statistical source data.

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Zhou, Y., Ding, M., Gao, S. et al. Optogenetic control of plant growth by a microbial rhodopsin. Nat. Plants 7, 144–151 (2021).

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