New Light on the Mechanism of Phototransduction in Phototropin
(2020) In Biochemistry 59(35). p.3206-3215- Abstract
Phototropins are photoreceptor proteins that regulate blue light-dependent biological processes for efficient photosynthesis in plants and algae. The proteins consist of a photosensory domain that responds to the ambient light and an output module that triggers cellular responses. The photosensory domain of phototropin from Chlamydomonas reinhardtii contains two conserved LOV (light-oxygen-voltage) domains with flavin chromophores. Blue light triggers the formation of a covalent cysteine-flavin adduct and upregulates the phototropin kinase activity. Little is known about the structural mechanism that leads to kinase activation and how the two LOV domains contribute to this. Here, we investigate the role of the LOV1 domain from C.... (More)
Phototropins are photoreceptor proteins that regulate blue light-dependent biological processes for efficient photosynthesis in plants and algae. The proteins consist of a photosensory domain that responds to the ambient light and an output module that triggers cellular responses. The photosensory domain of phototropin from Chlamydomonas reinhardtii contains two conserved LOV (light-oxygen-voltage) domains with flavin chromophores. Blue light triggers the formation of a covalent cysteine-flavin adduct and upregulates the phototropin kinase activity. Little is known about the structural mechanism that leads to kinase activation and how the two LOV domains contribute to this. Here, we investigate the role of the LOV1 domain from C. reinhardtii phototropin by characterizing the structural changes occurring after blue light illumination with nano- to millisecond time-resolved X-ray solution scattering. By structurally fitting the data with atomic models generated by molecular dynamics simulations, we find that adduct formation induces a rearrangement of the hydrogen bond network from the buried chromophore to the protein surface. In particular, the change in conformation and the associated hydrogen bonding of the conserved glutamine 120 induce a global movement of the β-sheet, ultimately driving a change in the electrostatic potential on the protein surface. On the basis of the change in the electrostatics, we propose a structural model of how LOV1 and LOV2 domains interact and regulate the full-length phototropin from C. reinhardtii. This provides a rationale for how LOV photosensor proteins function and contributes to the optimal design of optogenetic tools based on LOV domains.
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- author
- Henry, L. ; Berntsson, O. LU ; Panman, M. R. ; Cellini, A. ; Hughes, A. J. ; Kosheleva, I. ; Henning, R. and Westenhoff, S. LU
- organization
- publishing date
- 2020
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Biochemistry
- volume
- 59
- issue
- 35
- pages
- 10 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:85090505067
- pmid:32786255
- ISSN
- 0006-2960
- DOI
- 10.1021/acs.biochem.0c00324
- language
- English
- LU publication?
- yes
- id
- 331b80a9-01cf-4e74-a7fd-43cdde26dbee
- date added to LUP
- 2020-09-29 13:40:01
- date last changed
- 2024-06-26 23:09:29
@article{331b80a9-01cf-4e74-a7fd-43cdde26dbee,
abstract = {{<p>Phototropins are photoreceptor proteins that regulate blue light-dependent biological processes for efficient photosynthesis in plants and algae. The proteins consist of a photosensory domain that responds to the ambient light and an output module that triggers cellular responses. The photosensory domain of phototropin from Chlamydomonas reinhardtii contains two conserved LOV (light-oxygen-voltage) domains with flavin chromophores. Blue light triggers the formation of a covalent cysteine-flavin adduct and upregulates the phototropin kinase activity. Little is known about the structural mechanism that leads to kinase activation and how the two LOV domains contribute to this. Here, we investigate the role of the LOV1 domain from C. reinhardtii phototropin by characterizing the structural changes occurring after blue light illumination with nano- to millisecond time-resolved X-ray solution scattering. By structurally fitting the data with atomic models generated by molecular dynamics simulations, we find that adduct formation induces a rearrangement of the hydrogen bond network from the buried chromophore to the protein surface. In particular, the change in conformation and the associated hydrogen bonding of the conserved glutamine 120 induce a global movement of the β-sheet, ultimately driving a change in the electrostatic potential on the protein surface. On the basis of the change in the electrostatics, we propose a structural model of how LOV1 and LOV2 domains interact and regulate the full-length phototropin from C. reinhardtii. This provides a rationale for how LOV photosensor proteins function and contributes to the optimal design of optogenetic tools based on LOV domains.</p>}},
author = {{Henry, L. and Berntsson, O. and Panman, M. R. and Cellini, A. and Hughes, A. J. and Kosheleva, I. and Henning, R. and Westenhoff, S.}},
issn = {{0006-2960}},
language = {{eng}},
number = {{35}},
pages = {{3206--3215}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Biochemistry}},
title = {{New Light on the Mechanism of Phototransduction in Phototropin}},
url = {{http://dx.doi.org/10.1021/acs.biochem.0c00324}},
doi = {{10.1021/acs.biochem.0c00324}},
volume = {{59}},
year = {{2020}},
}