Photoreceptor Engineering to Modulate Plant Growth
Lead Research Organisation:
University of Glasgow
Department Name: College of Medical, Veterinary, Life Sci
Abstract
Light is critical for coordinating plant growth and development. Blue light (320-500 nm) in particular acts to regulate a wide range of responses that serve to promote growth. These processes include chloroplast relocation movements, leaf positioning and expansion, stomatal opening and phototropism, all of which influence a plant's photosynthetic competence by improving efficiency of light capture, reducing photodamage, and regulating gas exchange between leaves and the atmosphere. Collectively, these responses elicit dramatic effects on plant growth and are controlled by phototropin blue-light receptors. Therefore, manipulation of phototropin receptor activity offers additional opportunities to increase photosynthetic performance and promote growth under specific light conditions. Indeed, our recent results demonstrate the potential to alter plant growth through changes in phototropin reactivity. Hence, a major outcome of this work will be to establish a structural and functional blueprint for constructing engineered photoreceptors directed at optimising photosynthetic productivity under specific light conditions. This proposal therefore offers an additional approach to coordinate stepwise enhancements in photosynthetic performance with an aim to increasing yield that should ultimately offer new strategies to grow crops more efficiently. The work outlined in this proposal will also 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.
Technical Summary
Increasing plant biomass has the potential to offer solutions for the food, energy, and environmental challenges of the future. Enhancing photosynthetic capacity and efficiency are recognised in this regard as bottlenecks to raising plant productivity. Recent engineering strategies have targeted diverse aspects of photosynthesis. However, an additional approach would be to target physiological processes that serve to optimise photosynthetic productivity. These include phototropism, leaf flattening and positioning, solar tracking, chloroplast relocation and stomatal opening, all of which are regulated by phototropin blue light receptors. Thus, engineering phototropin function has the potential to modulate plant growth through changes in photosynthetic efficiency. By using a directed evolution approach, we have identified key amino acid changes that markedly increase or decrease phototropin reactivity. This proposal focuses on harnessing these findings to fine-tune photoreceptor reactivity with an aim to modulate plant growth through changes in photosynthetic performance in Arabidopsis thaliana. Given the high degree of sequence conservation between higher plant phototropins, the design principles established here should extend to plant species important for producing sustainable food supplies and alternative fuel sources. This project is therefore of central importance to understanding how light is integrated to control a variety of responses that collectively promote plant growth and will ultimately provide new strategies to manipulate yield for agronomic gain. Knowledge gained from this work will also have relevance in the design of photosensory modules for emerging optogenetic applications.
Planned Impact
Beneficiaries: Beneficiaries of the research will include: academic scientists interested in plant photobiology and plant biotechnology, synthetic biologists interested in the design of artificial photoreceptor systems, commercial organisations interested in developing new strategies to improve crop production, individuals (text books for teaching), and organisations involved in science communication to schools and to the wider public (e.g. Glasgow Science Centre). Phototropin research will also appeal to the general public who can relate to the early phototropism work of Charles Darwin and its impact on science and evolution.
Benefits: The impact of the research is derived from its relevance to understand how blue light coordinates a variety of processes that serve to optimise photosynthetic efficiency and promote plant growth and the potential relevance to crop improvement for agronomic gain. Phototropin blue light receptors elicit dramatic effects on plant growth by collectively regulating chloroplast relocation movements, leaf positioning and expansion, stomatal opening and phototropism, all of which influence a plant's photosynthetic competence by improving efficiency of light capture, reducing photodamage, and regulating gas exchange between leaves and the atmosphere. Thus, research on engineering phototropin function has the potential to generate new strategies to further modulate plant growth through changes in photosynthetic efficiency. Phototropin signalling pathways are also known to prime plant defence responses and potentiate pathogen resistance. Hence, the engineering strategies devised in this proposal could also prove useful towards improving pathogen tolerance. Phototropins are universal in higher plants. Therefore, this project has the potential, in the longer term, to create new avenues for crop improvement that could benefit farmers, consumers and the environment and contribute to the economic competitiveness of the UK. 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 of the RA will also benefit directly from collaborative aspects of the research with Prof. Getzoff (The Scripps Research Institute, San Diego).
Activities: The project will be continually managed by the PI to engage potential beneficiaries. The PI will publish the research in high-impact scientific journals, write reviews and book chapters and inform the University Media Relations Office of research highlights. Discussions with relevant commercial organisations will be initiated when appropriate to promote exploitation. The PI will communicate the research to school and university students via visits and University open days, initiate discussions with the Glasgow Science Centre, and present lectures at national and international conferences, as well as within Universities throughout the UK. The PI's web site will be routinely updated to communicate the research to the general public.
Benefits: The impact of the research is derived from its relevance to understand how blue light coordinates a variety of processes that serve to optimise photosynthetic efficiency and promote plant growth and the potential relevance to crop improvement for agronomic gain. Phototropin blue light receptors elicit dramatic effects on plant growth by collectively regulating chloroplast relocation movements, leaf positioning and expansion, stomatal opening and phototropism, all of which influence a plant's photosynthetic competence by improving efficiency of light capture, reducing photodamage, and regulating gas exchange between leaves and the atmosphere. Thus, research on engineering phototropin function has the potential to generate new strategies to further modulate plant growth through changes in photosynthetic efficiency. Phototropin signalling pathways are also known to prime plant defence responses and potentiate pathogen resistance. Hence, the engineering strategies devised in this proposal could also prove useful towards improving pathogen tolerance. Phototropins are universal in higher plants. Therefore, this project has the potential, in the longer term, to create new avenues for crop improvement that could benefit farmers, consumers and the environment and contribute to the economic competitiveness of the UK. 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 of the RA will also benefit directly from collaborative aspects of the research with Prof. Getzoff (The Scripps Research Institute, San Diego).
Activities: The project will be continually managed by the PI to engage potential beneficiaries. The PI will publish the research in high-impact scientific journals, write reviews and book chapters and inform the University Media Relations Office of research highlights. Discussions with relevant commercial organisations will be initiated when appropriate to promote exploitation. The PI will communicate the research to school and university students via visits and University open days, initiate discussions with the Glasgow Science Centre, and present lectures at national and international conferences, as well as within Universities throughout the UK. The PI's web site will be routinely updated to communicate the research to the general public.
Organisations
- University of Glasgow (Lead Research Organisation)
- Jagiellonian University (Collaboration)
- UNIVERSITY OF GLASGOW (Collaboration)
- Plant Bioscience Limited Technology (Collaboration)
- Southern Methodist University (Collaboration)
- Tianjin Institute of Industrial Biotechnology (Collaboration)
- University of Kyoto (Collaboration)
- UNIVERSITY OF ESSEX (Collaboration)
People |
ORCID iD |
John Christie (Principal Investigator) |
Publications
Agliassa C
(2018)
Geomagnetic field impacts on cryptochrome and phytochrome signaling
in Journal of Photochemistry and Photobiology B: Biology
Buckley AM
(2015)
LOV-based reporters for fluorescence imaging.
in Current opinion in chemical biology
Christie JM
(2021)
Optogenetics in plants.
in The New phytologist
Christie JM
(2018)
Shining Light on the Function of NPH3/RPT2-Like Proteins in Phototropin Signaling.
in Plant physiology
Cosentino C
(2015)
Optogenetics. Engineering of a light-gated potassium channel.
in Science (New York, N.Y.)
Fankhauser C
(2015)
Plant Phototropic Growth
in Current Biology
Hart JE
(2019)
Engineering the phototropin photocycle improves photoreceptor performance and plant biomass production.
in Proceedings of the National Academy of Sciences of the United States of America
Homans RJ
(2018)
Two photon spectroscopy and microscopy of the fluorescent flavoprotein, iLOV.
in Physical chemistry chemical physics : PCCP
Inoue SI
(2020)
CIPK23 regulates blue light-dependent stomatal opening in Arabidopsis thaliana.
in The Plant journal : for cell and molecular biology
Papanatsiou M
(2019)
Optogenetic manipulation of stomatal kinetics improves carbon assimilation, water use, and growth.
in Science (New York, N.Y.)
Petersen J
(2017)
Functional characterization of a constitutively active kinase variant of Arabidopsis phototropin 1.
in The Journal of biological chemistry
Schnabel J
(2018)
A chemical genetic approach to engineer phototropin kinases for substrate labeling.
in The Journal of biological chemistry
Sullivan S
(2016)
Functional characterization of Ostreococcus tauri phototropin.
in The New phytologist
Sullivan S
(2016)
Phytochrome A Mediates Blue-Light Enhancement of Second-Positive Phototropism in Arabidopsis.
in Frontiers in plant science
Sullivan S
(2019)
Deetiolation Enhances Phototropism by Modulating NON-PHOTOTROPIC HYPOCOTYL3 Phosphorylation Status.
in Plant physiology
Sullivan S
(2021)
Regulation of plant phototropic growth by NPH3/RPT2-like substrate phosphorylation and 14-3-3 binding.
in Nature communications
Sullivan S
(2016)
Functional characterization of Arabidopsis phototropin 1 in the hypocotyl apex
in The Plant Journal
Description | We have successfully engineered photoreceptors to improve photosynthetic productivity and plant growth. Publications have been published in Science and PNAS and a patent filed in connection with PBL for one of the approaches used. |
Exploitation Route | Further patent application/funding being discussed/pursued along with transfer of the technology to crop relevant species. |
Sectors | Agriculture Food and Drink Education |
Description | Research was publicised via poster displays at the Glasgow Science Centre for the general public. Interest in photobiological research was stimulated. In 2017, my group participated in a widely and well received public outreach event as a part of the Glasgow Botanic Gardens Bicentenary celebrations by presenting their research to the general public through fun activities and by unveiling a booklet that showcasing the rich history and diverse cutting-edge research carried out by the different plant science groups at Glasgow. Furthered in 2018 by showcasing plant science research at the Glasgow Science Festival. These activities were also continued in 2019. A key aim of the research was to engineer the photochemical reactivity of phototropin blue light receptors (phot1 and phot2) to manipulate plant growth and this was successfully achieved. A key challenge is to increase plant yield by altering photosynthetic productivity to secure food, energy, and environmental sustainability. In the model plant Arabidopsis thaliana, the plasma-membrane-associated phototropin kinases, phot1 and phot2, are activated by blue light and play important roles in regulating several responses that optimise photosynthetic efficiency. A main outcome from this research shows that the photocycle of phot1 and phot2 can be modulated through protein engineering to increase their sensitivity to light. Consequently, Arabidopsis plants with these engineered phototropins exhibit more rapid and robust chloroplast movement responses and improved leaf positioning and expansion, leading to improved biomass accumulation under light-limiting conditions. We anticipate that this approach will contribute to coordinating stepwise enhancements in photosynthesis to increase yield by growing crops more efficiently, particularly in low-light environments, which could be relevant to agricultural practices, such as intercropping. The work therefore establishes a robust approach for engineering photosensory modules which can be further expanded to optimise leaf photosynthesis. Accelerating the photocycle of phot2 for instance would increase the light intensity threshold for chloroplast avoidance movement. This, in combination with the slow photocycle tuning of phot1, could be harnessed to synchronise their actions more effectively over a wider range of light conditions without causing detrimental high light stress. |
First Year Of Impact | 2017 |
Sector | Agriculture, Food and Drink,Education |
Impact Types | Societal |
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. |
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 | 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 | Mike Blatt |
Organisation | University of Glasgow |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Collaboration has capitalised on using synthetic photosensory tools to manipulate plant physiology. The work produced has just been accepted for publication in Science. A patent application has been filed. |
Collaborator Contribution | Electrophysiological and physiological characterisation of transgenic Arabidopsis. |
Impact | The work produced has just been accepted for publication in Science. |
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 | Noriyuki Suetsugu |
Organisation | University of Kyoto |
Country | Japan |
Sector | Academic/University |
PI Contribution | This works is focussed on characterising NPH3/RPT2 proteins in plants and their contribution to optimising photosynthetic light capture. |
Collaborator Contribution | Dr Suetsugu visited and worked with us as a JSPS research fellow. |
Impact | One review has been published and another manuscript submitted to Plant Physiology. |
Start Year | 2016 |
Description | Protein Crystallography |
Organisation | Southern Methodist University |
Country | United States |
Sector | Academic/University |
PI Contribution | Provided constructs for protein expression/purification |
Collaborator Contribution | Protein Crystallography |
Impact | In progress |
Start Year | 2016 |
Description | iLOV |
Organisation | Tianjin Institute of Industrial Biotechnology |
Country | China |
Sector | Charity/Non Profit |
PI Contribution | Newton fellowship for IBioIC student to visit Tianjin to explore the utility of the iLOV FP in industrial bioprocessing. |
Collaborator Contribution | Hosting PhD student and training. |
Impact | N/A |
Start Year | 2017 |
Title | LOV-based optogenetics for plants |
Description | Artificial light-activated K+ channel that has been used to improve carbon assimilation, water use and growth in plants. |
Type Of Technology | New/Improved Technique/Technology |
Year Produced | 2019 |
Impact | Science paper pending and patent filed. |
Description | 6th and 7th Edition Plant Physiology and Development |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Undergraduate students |
Results and Impact | Worked with other editors and authors to formulate chapters for the teaching text book Plant Physiology. Edition still in press so difficult to gage at present but should provide an instrumental guide for school pupils and students. |
Year(s) Of Engagement Activity | 2015,2016,2017 |
Description | Botanics bicentenary |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | My group participated in a widely and well received public outreach event as a part of the Glasgow Botanic Gardens Bicentenary celebrations by presenting their research to the general public through fun activities and by unveiling a booklet that showcasing the rich history and diverse cutting-edge research carried out by the different plant science groups at Glasgow. |
Year(s) Of Engagement Activity | 2017 |
URL | https://www.ugplantsci.org |
Description | Chair of the GRC on Photosensory Receptors and Signal Transduction |
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 | I organised this biennial meeting which was attended by academics, students and from Industry as well as NASA. The meeting was highly successful based on questionnaire feedback and will run again in two years time. |
Year(s) Of Engagement Activity | 2016 |
Description | DFG Roundtable Discussion on Photoreceptors |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Other audiences |
Results and Impact | Invited to attend DFG discussion group evaluating status and future scope of photoreceptor research. |
Year(s) Of Engagement Activity | 2017 |
Description | Gatsby Summer School |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Schools |
Results and Impact | I gave a plenary lecture and participated in the summer school to encourage teachers and students to consider plant science and photo biological research. |
Year(s) Of Engagement Activity | 2015 |
URL | http://www.slcu.cam.ac.uk/outreach/gatsbyplants |
Description | Glasgow Science Festival: Science Sunday, June 2018 |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Contributed to and participated in activities for the Glasgow Science Festival: Science Sunday, June 2018 |
Year(s) Of Engagement Activity | 2018 |
Description | Interaction with James Hutton Institute, Dundee. |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Study participants or study members |
Results and Impact | Visited to initiate collaborative research. Collaborations now secured through a joint PhD student. |
Year(s) Of Engagement Activity | 2018 |
Description | Invited participant at the New Phytologist Next Generation Scientist meeting. John Innes Conference Centre, Norwich Research Park, Norwich, UK, July 2017. |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Other audiences |
Results and Impact | Invited participant at the New Phytologist Next Generation Scientist meeting. John Innes Conference Centre, Norwich Research Park, Norwich, UK, July 2017.Myself (Editor, New Phytologist), Chris Surridge (Chief Editor, Nature Plants), Anne Knowlton (Senior Editor, Current Biology), Adam Wheeler (Senior Publisher, Wiley) and Ashlynne Merrifield (Publisher, Taylor & Francis) sat on an expert panel and offered advice on the processes of communicating science and publishing, as well as an Q&A sessions. |
Year(s) Of Engagement Activity | 2017 |
Description | Invited seminar speaker, Freie Universitat Berlin |
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 | Invited as one of two plenary speakers to a workshop on photobiology organised by PhD students at the Freie Universitat Berlin. Participated in discussions of future research directions |
Year(s) Of Engagement Activity | 2015 |
Description | Invited speaker and session chair, International Congress of Light and Light Barcelona, August 2019. |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Study participants or study members |
Results and Impact | Invited speaker and session chair, International Congress of Light and Light Barcelona, August 2019. Presented two talks in different session on opotgenetic strategies to improve plant growth. |
Year(s) Of Engagement Activity | 2019 |
Description | Invited speaker and session chair, International Symposium on Plant Photobiology, Barcelona, June 2019. |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Invited speaker and session chair, International Symposium on Plant Photobiology, Barcelona, June 2019. Presented research on how to engineer photoreceptor to improve plant growth. |
Year(s) Of Engagement Activity | 2019 |
Description | Invited speaker, SEB Meeting - From Proteome to Phenotype (Dec, 2017). Edinburgh, UK |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Study participants or study members |
Results and Impact | Invited speaker, SEB Meeting - From Proteome to Phenotype (Dec, 2017). Edinburgh, UK. Presented research on how to engineer photoreceptor to improve plant growth. |
Year(s) Of Engagement Activity | 2017 |
Description | Invited speaker, Symposium in Honour of Winslow Briggs (April, 2018). Stanford, USA. |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Study participants or study members |
Results and Impact | Invited speaker, Symposium in Honour of Winslow Briggs (April, 2018). Stanford, USA. Prof. Briggs sadly passed away at the age of 90 in Feb. 2019. Fund raising has been established to provide support/honour for plant scientists in his recognition. |
Year(s) Of Engagement Activity | 2018 |
Description | Nagoya Institute of Technology International Symposium on Frontier Materials |
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 | Invited speaker and workshop participant |
Year(s) Of Engagement Activity | 2016 |
Description | Royal Society |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | Yes |
Geographic Reach | National |
Primary Audience | Other audiences |
Results and Impact | Invited to serve on the Royal Society University Research Fellowship (URF) Biological Panel as of 2015. Yet to implement. |
Year(s) Of Engagement Activity | 2015 |
Description | Summer students |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Undergraduate students |
Results and Impact | Host summer students to gain laboratory experience and educate them about plant science. Can be effective in changing students views towards plant science and help make them decide to pursue this as a degree or career. |
Year(s) Of Engagement Activity | Pre-2006,2006,2007,2008,2011,2012,2013,2014 |