A protein scaffold essential for K+ transport and stomatal control
Lead Research Organisation:
University of Glasgow
Department Name: School of Life Sciences
Abstract
This proposal builds on the discovery in this laboratory of an unusual SNARE protein complex that is essential for K+ channel regulation in Arabidopsis, and of our recent finding of its impact on K+ uptake by the roots and plant growth. Because the SNARE, SYP121, is already known to have roles in pathogen defence and cell volume responses meidated by the plant hormone abscisic acid (ABA), these findings offer the first substantive evidence that physically links the protein complex to actions in abiotic stress, mineral nutrition, water use efficiency (defined as the amount of dry matter produced per unit of water transpired through stomata) and cell expansion in the plant. 'Closing the circle' of K+ channel control, its contributions to K+ assimilation, water flux and cell volume control in the growing plant is expected to yield substantive insights in future efforts towards 'hardening' and development of water-effcient crops. In general, eukaryotic cells engage SNARE proteins as part of a well-defined mechanism for traffic of membrane vesicles, proteins and soluble cargo between compartments within the cell. Work from this laboratory first identified genes encoding two plasma membrane SNAREs from tobacco and Arabidopsis, and demonstrated their association with the ABA signalling cascade leading stomata to close and reduce water loss from the plant. Much is known about these cellular signals as well as the mechanisms they engage in regulating transmembrane ion flux. By contrast, we have little knowledge of the mechanisms coordinating ion transport with cellular volume and membrane surface in guard cells. Indeed, how plant cells regulate transport of osmotically-active solutes (especially of K+) in parallel with cell volume, whether reversible as in guard cells or during irreversible expansive growth, remains a matter of considerable debate. Knowing how transport is coordinated with changes in cell surface area will be of great fundament importance to understanding cell volume control in plants generally, and is likely to have practical relevance in our ability to manipulate the growth and homeostasis of plants, for example in altering stomatal controls to improve water use efficiency of crops. Our working hypothesis is that SNARE-K+ channel interaction serves as a molecular governor, analogous to the mechanical invention of James Watt, to coordinate channel-mediated uptake of the osmotically-active K+ ion with cell expansion We want to explore the molecular mechanics of the interaction, its implications for such a governor model in cell volume control and, equally, we want to examine its potential for applications in agriculture. Our immediate goals are (1) to explore the dynamics of the protein partners and their interactions, (2) to analyse their impact on ion transport and its coordination with membrane traffic, and (3) to assess their importance for stomatal function and water use by plants under stress.
Technical Summary
This proposal builds on our discovery of an unusual SNARE protein complex that is essential for K+ channel regulation in Arabidopsis, and of our recent finding of its impact on K+ uptake and plant growth. In general, eukaryotic cells engage SNARE proteins as part of a well-defined mechanism for traffic of membrane vesicles, proteins and soluble cargo between compartments within the cell. Our discovery of a SNARE-K+ channel complex in plants, and evidence of its unusual role in controlling K+ uptake as well as facilitating cell expansion, provides the very first opportunity to explore how such interactions regulate transport of osmotically-active solutes in parallel with cell expansion in plants. Knowing how transport is coordinated with changes in cell surface area will be of great importance to understanding cell volume control in plants generally, and is likely to have practical relevance in our ability to manipulate the growth and homeostasis, for example in altering stomatal controls to improve water use efficiency of crops. Our working hypothesis is that SNARE-K+ channel interaction serves as a molecular 'governor' to coordinate channel-mediated uptake of the osmotically-active K+ ion with cell expansion. The immediate goals are to analyse the molecular basis for the interaction, its implications for cell volume control and, equally, to examine its potential for applications in agriculture. These studies will make use of site-directed mutagenesis, multi-component protein interaction analysis, electrophysiology and single-cell imaging technologies to identify the protein motifs essential for SNARE-K+ channel interaction and to characterise their role(s) in K+ transport control in parallel with changes in cell volume.
Planned Impact
This proposal is for fundamental research developing new concepts at the core of ideas emerging within the international plant cell biology community. The research should stimulate thinking about these topics and help facilitate a paradigm shift in approach. These studies will also extend our recent development of a novel 'bridge' assay for high-throughput molecular interaction analysis. Thus, the research is expected to benefit fundamental researchers as well as industry through conceptual developments as well as the introduction of new technologies for the analysis of multicomponent systems. The research will feed into higher education training programmes through research training at the postgraduate and postdoctoral levels. Finally it will help guide future efforts in applications to agricultural/industrial systems. MRB has established links with industrial/technology transfer partners (Agrisera, Dualsystems, Plant Bioscience) and research institutes (SCRI and JIC) to take advantage of these developments. Further details of these, and additional impacts will be found in Part 1 of the Case for Support and in the attached Impact Plan.
People |
ORCID iD |
Michael Blatt (Principal Investigator) |
Publications
Cai S
(2017)
Speedy Grass Stomata: Emerging Molecular and Evolutionary Features.
in Molecular plant
Cai S
(2017)
Evolutionary Conservation of ABA Signaling for Stomatal Closure.
in Plant physiology
Chen ZH
(2017)
Molecular Evolution of Grass Stomata.
in Trends in plant science
Chen ZH
(2010)
Dynamic regulation of guard cell anion channels by cytosolic free Ca2+ concentration and protein phosphorylation.
in The Plant journal : for cell and molecular biology
Chen ZH
(2012)
Systems dynamic modeling of the stomatal guard cell predicts emergent behaviors in transport, signaling, and volume control.
in Plant physiology
Chen ZH
(2012)
Protocol: optimised electrophyiological analysis of intact guard cells from Arabidopsis.
in Plant methods
Eisenach C
(2012)
The trafficking protein SYP121 of Arabidopsis connects programmed stomatal closure and K? channel activity with vegetative growth.
in The Plant journal : for cell and molecular biology
Eisenach C
(2014)
Clustering of the K+ channel GORK of Arabidopsis parallels its gating by extracellular K+.
in The Plant journal : for cell and molecular biology
Feroz H
(2018)
Light-Driven Chloride Transport Kinetics of Halorhodopsin.
in Biophysical journal
Description | Work on this project built on a long-standing interest in understanding how plants control turgor and cell volume. On the basis of these studies, we can now show that direct physical interactions between a subset of ion channels (for solute uptake and turgor) and a conserved group of vesicle-trafficking proteins are key to mutual control of the turgor and cell expansion. A key finding of this work is the direct coupling of vesicle traffic with ion channels to confer a coupling to solute uptake and growth. |
Exploitation Route | The work completely rewrites the textbooks on how vesicle traffic is controlled in eukaryotes, demonstrating that plants have a unique capacity to coordinate traffic with solute uptake. The knowledge gained should, in the long run, contribute to our understanding and application of plant growth. |
Sectors | Agriculture Food and Drink Education Environment Other |
URL | http://www.psrg.org.uk |
Title | 2in1 vector systems |
Description | Synthetic biology vectors for transient and stable transformation with quantitative visual reporting on cell-by-cell basis |
Type Of Material | Technology assay or reagent |
Year Produced | 2009 |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and over 100 research groups worldwide Vector system distributions to more than 500 research groups worldwide |
URL | http://psrg.org.uk |
Title | EZ-Rhizo |
Description | Computer software tool for quantitative measurement and analysis of root growth/development |
Type Of Material | Physiological assessment or outcome measure |
Year Produced | 2010 |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and research groups worldwide Online distribution has been accessed through the laboratory website with site views at a rate of >500 per month |
URL | http://psrg.org.uk |
Title | Henry |
Description | Software for electrophysiology and imaging data aquisition and analysis |
Type Of Material | Technology assay or reagent |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and research groups worldwide Online distribution has been accessed through the laboratory website with site views at a rate of >500 per month |
URL | http://psrg.org.uk |
Title | Multicistronic vector systems |
Description | Synthetic biology vector systems for transient and stable transformation for expressing multiple, tagged proteins and for quantitative analysis of membrane traffic and transport |
Type Of Material | Technology assay or reagent |
Year Produced | 2010 |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and over 100 research groups worldwide Vector system distributions to more than 500 research groups worldwide |
URL | http://psrg.org.uk |
Title | OnGuard |
Description | Systems biology software for quantitative modelling of cellular transport and homeostasis |
Type Of Material | Physiological assessment or outcome measure |
Year Produced | 2012 |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and research groups worldwide Online distribution has been accessed through the laboratory website with site views at a rate of >500 per month |
URL | http://psrg.org.uk |
Title | SUS vector systems |
Description | Synthetic biological vector systems for protein-protein interaction screening |
Type Of Material | Technology assay or reagent |
Year Produced | 2010 |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and over 100 research groups worldwide Vector system distributions to more than 500 research groups worldwide |
URL | http://psrg.org.uk |
Title | Software tools for electrophysiology and imaging |
Description | The laboratory continues to develop and refine software/hardware tools for data acquisition and analysis relevant to electrophysiology, single-cell imaging and analysis. These activities are long-standing and open-ended, and develop in line with the current research activities and needs of the laboratory. All software and related packages are made freely available to the research community through the laboratory website at psrg.org.uk |
Type Of Material | Technology assay or reagent |
Provided To Others? | Yes |
Impact | The various software tools and packages have furthered the research activities of the laboratory since the 1990s and continue to provide key support and drivers for advancing much of current research. These tools and packages are disseminated, on average, to over 100 laboratories per year. |
URL | http://psrg.org.uk |
Title | EZ-Rhizo |
Description | Software for quantitative trait analysis and acquisition for root growth/development |
Type Of Material | Database/Collection of data |
Year Produced | 2010 |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and research groups worldwide Online distribution has been accessed through the laboratory website with site views at a rate of >500 per month |
URL | http://psrg.org.uk |
Title | Henry |
Description | Software package for electrophysiology and imaging data acquisition and analysis |
Type Of Material | Data handling & control |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and research groups worldwide Online distribution has been accessed through the laboratory website with site views at a rate of >500 per month |
URL | http://psrg.org.uk |
Title | OnGuard |
Description | Quantitative systems biology modelling of cellular transport and homeostasis |
Type Of Material | Computer model/algorithm |
Year Produced | 2012 |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and research groups worldwide Online distribution has been accessed through the laboratory website with site views at a rate of >500 per month |
URL | http://psrg.org.uk |
Title | SDM-assist |
Description | Software for molecular primer design that enables introduction of silent markers for molecular cloning |
Type Of Material | Data analysis technique |
Year Produced | 2013 |
Provided To Others? | Yes |
Impact | Multiple publications from my own research group and research groups worldwide Online distribution has been accessed through the laboratory website with site views at a rate of >500 per month |
URL | http://psrg.org.uk |
Description | PBL |
Organisation | Plant Bioscience Limited Technology |
Country | United Kingdom |
Sector | Private |
PI Contribution | IPR on ABA receptor technology and ABA signalling |
Collaborator Contribution | Funding related to IPR on ABA receptor technology and ABA signalling |
Impact | Multiple outcomes in publications and industrial contacts |
Description | PSG |
Organisation | POSCO - South Korea |
Country | Korea, Republic of |
Sector | Private |
PI Contribution | Base support for meetings and exchange of materials |
Collaborator Contribution | Base support for meetings and exchange of materials |
Impact | Base support for meetings and exchange of materials |
Title | Software tools and packages for electrophysiology and imaging |
Description | The laboratory continues to develop and refine software/hardware tools for data acquisition and analysis relevant to electrophysiology, single-cell imaging and analysis. These activities are long-standing and open-ended, and develop in line with the current research activities and needs of the laboratory. All software and related packages are made freely available to the research community through the laboratory website at psrg.org.uk |
Type Of Technology | Software |
Impact | The various software tools and packages have furthered the research activities of the laboratory since the 1990s and continue to provide key support and drivers for advancing much of current research. These tools and packages are disseminated, on average, to over 100 laboratories per year. |
URL | http://psrg.org.uk |
Description | International online services |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Prof. Blatt and members of his laboratory have contributed to various media events over the years, including online interview contributions (e.g. People behind the Science, a US-based media program) |
Year(s) Of Engagement Activity | Pre-2006,2006,2008,2011,2015,2016,2017,2018 |
Description | Invited presentations |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | I regularly speak to audiences, from small groups (5-20) to large audiences (>1000) in a variety of settings. In addition to teaching and extramural activities associated with the university, I also speak on invitation to national and international groups a number of times each year and in a variety of settings, academic as well as public. I also reach audiences through short video presentations mounted on the web, these primarily via my laboratory website and the ASPB websites. Anyone reading this entry is welcome to visit these sites to learn more. The impacts arising from my presentations are varied. For example, a common consequence of my speaking in academic settings is to attract potential researchers to visit my laboratory and, frequently, to interest potential collaborators and students/postdocs to my research group. At scientific meetings, my talks often attract interest also from researchers interested in the various tools and materials that my research has produced, including the various vector systems and software packages that I |
Year(s) Of Engagement Activity | Pre-2006,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018 |
URL | http://psrg.org.uk |
Description | Schools and displays |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | As these were multiple events, this question is not informative or useful. Participants varied from numbers in the tens to several thousands Extensive training of participating laboratory members as well as broad scope reach to schools and communities, in the case of the GCC science days to the west of Scotland and in the case of the IFPD activities to audiences within and outside the UK |
Year(s) Of Engagement Activity | 2010,2011,2012,2013,2014,2015,2016,2017,2018 |
URL | http://psrg.org.uk |
Description | Teaching Tools |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Schools |
Results and Impact | The PI has supported the editor in developing these tools since their inception in 2009 and has contributed to recent tools relating to membranes and transport education The Tool received an international award in 2010 for excellence in education and has an acknowledged takeup worldwide in over 3000 institutions |
Year(s) Of Engagement Activity | 2009,2010,2011,2012,2013,2014,2015,2016,2017,2018 |
URL | http://psrg.org.uk |
Description | Teaching Tools |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Schools |
Results and Impact | The PI has supported the editor in developing these tools since their inception in 2009 and has contributed to recent tools relating to membranes and transport education The Tool received an international award in 2010 for excellence in education and has an acknowledged takeup worldwide in over 3000 institutions |
Year(s) Of Engagement Activity | 2009,2010,2011,2012,2013,2014,2015,2016,2017,2018 |
URL | http://psrg.org.uk |