Coordinated Photoreceptor Engineering for Improved Biomass Production
Lead Research Organisation:
University of Glasgow
Department Name: College of Medical, Veterinary, Life Sci
Abstract
A key challenge for plant biologists has been to increase plant yield by altering photosynthetic productivity to secure food, energy and environmental sustainability. Phototropin receptor kinases (phot1 and phot2) play an important role in this regard by coordinating multiple light-capturing processes. These include phototropism, chloroplast movements, leaf positioning, leaf expansion and stomatal opening all of which influence a plant's photosynthetic competence by improving the efficiency of light capture, reducing photodamage, and regulating gas exchange between leaves and the atmosphere. However, little effort has been made to target these pathways for improving biomass production.
We have recently shown that targeted engineering can be used successfully to modify the light-sensing properties of the phototropins and increase their sensitivity to light. Plants with these engineered photoreceptors exhibit more rapid and robust chloroplast movement responses and improved leaf positioning and expansion, leading to over 2-fold increases biomass accumulation under light-limiting conditions. These findings demonstrate the feasibility of engineering photoreceptors for improved plant growth and offer additional opportunities for enhancing plant yield through increases in photosynthetic competence.
This proposal capitalises on these findings and will use a combinatorial protein engineering strategy to better synchronise the actions of the phototropins more effectively over a wider range of light conditions without causing detrimental high-light stress. Design principles for better synchronisation between phototropin receptors will be established first in Arabidopsis and extended to crops using barley as a model. Thus, a major outcome of this interlinked effort will be to establish a structural and functional blueprint for constructing engineered photoreceptors that will provide a non-transgenic, genome editing-based approach to coordinate stepwise enhancements in photosynthetic performance with an aim to increasing crop yield.
This work will concurrently generate new photoreceptor components with tailored photochemical properties that will have utility in generating synthetic protein-based switches designed to regulate target cellular activities by light. As our knowledge of phototropin receptor signalling is still far complete, this proposal will also exploit the availability of a novel desensitised photoreceptor mutant background, identified from our phototropin engineering work, to identify new components of phototropin signalling through genetic suppressor screening. Together, the fundamental and applied aspects of this research will expand our understanding of phototropin receptor function and harness the ability to fine tune their action as a bona fide means to modulate yield for agronomic gain.
We have recently shown that targeted engineering can be used successfully to modify the light-sensing properties of the phototropins and increase their sensitivity to light. Plants with these engineered photoreceptors exhibit more rapid and robust chloroplast movement responses and improved leaf positioning and expansion, leading to over 2-fold increases biomass accumulation under light-limiting conditions. These findings demonstrate the feasibility of engineering photoreceptors for improved plant growth and offer additional opportunities for enhancing plant yield through increases in photosynthetic competence.
This proposal capitalises on these findings and will use a combinatorial protein engineering strategy to better synchronise the actions of the phototropins more effectively over a wider range of light conditions without causing detrimental high-light stress. Design principles for better synchronisation between phototropin receptors will be established first in Arabidopsis and extended to crops using barley as a model. Thus, a major outcome of this interlinked effort will be to establish a structural and functional blueprint for constructing engineered photoreceptors that will provide a non-transgenic, genome editing-based approach to coordinate stepwise enhancements in photosynthetic performance with an aim to increasing crop yield.
This work will concurrently generate new photoreceptor components with tailored photochemical properties that will have utility in generating synthetic protein-based switches designed to regulate target cellular activities by light. As our knowledge of phototropin receptor signalling is still far complete, this proposal will also exploit the availability of a novel desensitised photoreceptor mutant background, identified from our phototropin engineering work, to identify new components of phototropin signalling through genetic suppressor screening. Together, the fundamental and applied aspects of this research will expand our understanding of phototropin receptor function and harness the ability to fine tune their action as a bona fide means to modulate yield for agronomic gain.
Technical Summary
The ability to enhance photosynthetic capacity remains a recognised bottleneck to improving plant productivity. Phototropin receptor kinases (phot1 and phot2) play an important role in this regard as they coordinate multiple light-capturing processes that serve to maximise photosynthetic efficiency and promote growth. However, little effort has been made to target these pathways for improved biomass production. Our aims are (1) to optimise photocycle engineering of phot1 and phot2 in Arabidopsis with the goal of better synchronising their activities for gains in photosynthetic performance over a wider range of light conditions (2) apply these design principles to barley (Hordeum vulgrae) to increase productivity (3) establish a structural and functional blueprint for altering phot action that will be widely applicable across plant species and (4) capitalise on our photoreceptor engineering progress by using a novel, desensitised phot mutant background for genetic suppressor screening to identify new signalling components. This proposal integrates both fundamental and applied research that will expand our understanding of phototropin receptor kinase signalling and harness key optogenetic principles (tuning optical sensitivity for gain of function) to establish photoreceptor engineering as a bona fide means to modulate yield for agronomic gain. It builds on our recent success with improving biomass production in Arabidopsis by targeting phototropin receptors for optogenetic manipulation. The proposal draws on established methodologies to expand the array of phototropin variants with altered photochemical properties and identify the most promising of these prior to their use in Arabidopsis and barley. Given the high degree of sequence conservation between higher plant phototropins, the design principles established here should extend to other agronomically important plant species and further expand the array of phototropin-based modules for optogenetic applications.
Planned Impact
This proposal combines practical and fundamental research that is central to concepts emerging from the fields of plant photobiology and optogenetics. The research will stimulate new thinking around ways to improve crop yield and offers new strategies to manipulate plant biomass through alterations in photosynthetic performance. The research therefore has potential to create a new engineering framework for crop improvement that could, in the long-term, benefit farmers, consumers and the environment and contribute to the economic competitiveness of the UK. Commercial organisations interested in implementing new approaches to manipulate plant growth, particularly by altering processes associated with regulating photosynthetic efficiency will also benefit in the longer term. Likewise, these organisations together with fundamental researcher will benefit from the design principles for fine tuning the action of LOV-based optogenetic tools. Additional impact is proposed through summer studentships to develop and implement outreach resources designed to engage the general public and school pupils in key concepts of photobiology, plant science and sustainability. Likewise, the staff assigned to the project will obtain knowledge and expertise that can be applied in related research fields or more widely in the commercial or public sectors. Career progression and training of the staff will also benefit directly from the collaborative and inter-disciplinary nature of the project. Hence, the research will feed directly into higher education training programmes. Finally, the research will contribute to UK competitiveness and quality of life through agro-industrial applications. The PI and Co-Is have established links with industrial/technology transfer partners and research institutes to take advantage of development arising from the research.
Organisations
- University of Glasgow (Lead Research Organisation)
- Jagiellonian University (Collaboration)
- Bayer (Collaboration)
- Plant Bioscience Limited Technology (Collaboration)
- Southern Methodist University (Collaboration)
- John Innes Centre (Collaboration)
- UNIVERSITY OF DUNDEE (Collaboration)
- UNIVERSITY OF ESSEX (Collaboration)
Publications
Kjeldsen A
(2022)
The fluorescent protein iLOV as a reporter for screening of high-yield production of antimicrobial peptides in Pichia pastoris.
in Microbial biotechnology
Sullivan S
(2021)
Regulation of plant phototropic growth by NPH3/RPT2-like substrate phosphorylation and 14-3-3 binding.
in Nature communications
Waksman T
(2023)
Phototropin phosphorylation of ROOT PHOTOTROPISM 2 and its role in mediating phototropism, leaf positioning, and chloroplast accumulation movement in Arabidopsis.
in The Plant journal : for cell and molecular biology
Description | This work has led to a new understanding of how light controls the growth and development of plants. It has uncovered new molecular information on how photoreceptors located within a plant cell, can switch on cellular process to establish important light capturing responses, including phototropism, leaf positioning and chloroplast movement, all of which optimise photosynthetic productivity and growth. Our findings provide new information on the how phototropin photoreceptors attach to the plasma membrane and how their spatiotemporal dynamics, oligomeric status change upon light activation. More importantly, we have made important advances in understanding how these receptor proteins initiate specific cellular signalling pathways from the plasma membrane by directly phosphorylating members of the NPH3/RPT2-like (NRL) protein family. Our establishment a of a new means to identify phototropin kinase substrates (kinase gatekeeper engineering) has been instrumental in moving this field forward. |
Exploitation Route | The outcomes have provided key progress in address fundamental gaps in our knowledge of how phototropin blue light receptors initiate signalling from the plasma membrane in plants. In particular, this progress will be harnessed by researchers in the field to further investigate the biochemical function and mode of action of NRL proteins in plants. |
Sectors | Agriculture Food and Drink Construction Education |
Description | At present, our advances in engineering photoreceptor function has attracted interested from Bayer Crop Science. This interest is at a very early stage but something that we will pursue as progress continues. |
First Year Of Impact | 2018 |
Sector | Agriculture, Food and Drink |
Title | BLINK1 |
Description | Light regulated potassium channel that has potential in neural silencing. Now demonstrated utility in plants (Science paper pending). Patent has been filed in collaboration with PBL. US patent application 17/431,984; US patent grant 11,542,518. |
Type Of Material | Technology assay or reagent |
Year Produced | 2015 |
Provided To Others? | Yes |
Impact | Published in Science and awaiting further examination of its utility for optogenetics. |
Title | GORK Patent |
Description | Engineered K+ channel for manipulating plant physiological responses using blue light. Patent Application No. PCT/EP2023/053078 - PBL Ref: 20.665 |
Type Of Material | Technology assay or reagent |
Year Produced | 2021 |
Provided To Others? | No |
Impact | No impacts as yet as still to be published. |
Description | BLINK Patent |
Organisation | Plant Bioscience Limited Technology |
Country | United Kingdom |
Sector | Private |
PI Contribution | Data that has now secured a patent filing. |
Collaborator Contribution | Patent filing. |
Impact | Patent filed. |
Start Year | 2019 |
Description | John Innes Centre |
Organisation | John Innes Centre |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Work on barely is being carried out in collaboration with Wendy Harwood at JIC. |
Collaborator Contribution | JIC will perform gene editing in barely to introduce point mutations into phototropin blue light receptors that can modulate their photosensitivity. |
Impact | Work with barley will commence later this year. |
Start Year | 2021 |
Description | Justyna Labuz |
Organisation | Jagiellonian University |
Country | Poland |
Sector | Academic/University |
PI Contribution | We have successfully engineered the activity of phototropin receptors to modulate plant growth. |
Collaborator Contribution | Justyna Labuz has characterised chloroplast movement responses. |
Impact | A manuscript based on our work has been submitted to PNAS. |
Start Year | 2017 |
Description | Matt Jones |
Organisation | University of Essex |
Department | School of Biological Sciences |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Collaborative research on engineered photoreceptors. |
Collaborator Contribution | Collaborative research on engineered photoreceptors. |
Impact | Initial data obtained and studies being extended to contribute to publication. |
Start Year | 2017 |
Description | NMR |
Organisation | Southern Methodist University |
Country | United States |
Sector | Academic/University |
PI Contribution | Collaborative work using NMR spectroscopy for protein structure. |
Collaborator Contribution | Collaborative work using NMR spectroscopy for protein structure. Hosted visiting PhD student. |
Impact | New data that should contribute to publication. |
Start Year | 2016 |
Description | Phosphoproteomics |
Organisation | University of Dundee |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Christie and Lamont are collaborating to identify phosphorylation control of higher plant phototropism. |
Collaborator Contribution | Christie is leading the research and Lamont is providing expertise and facilities to characterise phosphorylation events associated with this process. |
Impact | Research published in Mol. Plant 1, 178-194 and in several review articles. Data has been presented at numerous international scientific conferences. |
Start Year | 2006 |
Description | Preliminary discussions with Bayer |
Organisation | Bayer |
Department | Bayer CropScience Ltd |
Country | United Kingdom |
Sector | Private |
PI Contribution | Initial discussions with Bayer have been made on how they could harness the approach we are taking to manipulate photosynthetic productivity. |
Collaborator Contribution | Very much an open dialogue at present until we translate our findings to a model crop. |
Impact | None yet. |
Start Year | 2022 |
Description | Host to school visit |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | Hosted school pupils for 1 week from Kelvinside Academy for them to learn and appreciate plant science research. |
Year(s) Of Engagement Activity | 2023,2024 |
Description | Invited speaker |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Plenary speaker, Young Researchers Symposium on Plant Photobiology, Online Event. Provided a historical overview of my research, career and discussed professional development, career plans with postgraduate students. |
Year(s) Of Engagement Activity | 2022 |
Description | New Phytologist Workshop: introducing Transformative Plant Biotechnology |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Audience comprised of early career researchers and the event focussed on discussing the key challenges facing plant biotechnology, commercialisation of approaches as well as covering key advances in the field. |
Year(s) Of Engagement Activity | 2023 |