PDWallMech: Harnessing PlasmoDesma Wall Mechanics for plant biotech and biomaterials

Plant cells communicate with each other despite the rigid cell wall surrounding them. Communication is essential to coordinate development and responses to environmental inputs perceived locally or in distant organs. Some small molecules can move freely between cells using cell specific transport machineries. Cell walls limit diffusion of larger molecules, such as proteins and RNAs, however these can move via small channels that connect the insides of neighboring cells known as Plasmodesmata (singular, plasmodesma). Plasmodesmata function impacts all aspects of plant growth and development, including spreading of diseases, capacity to exploit soils resources, adaptation and survival to climatic changes. Despite their fundamental importance to all forms of plant life, we know very little about plasmodesmata and consequently this is one of the most promising but least exploited targets when developing new strategies to improve crop growth and resilience to climate change. The work that will be carried out in this project will fill key knowledge gaps on plasmodesmata, such as how different components in the surrounding cell walls affects plasmodesmata structural organization and function in different plants, cells and tissues. The mechanical properties of cell wall components affecting plasmodesmata function will be analysed to identify genes that can be targeted to modify intercellular communication, plant growth and environmental resilience. I will develop plant-type specific platforms that allow exploitation of plasmodesmata knowledge for the improvement of desirable crop traits, thus addressing their untapped potential to modify root branching (to improve access to water and nutrients uptake in depleted soils), resistance to viruses (plasmodesmata serve as a conduit for virus spreading) or the response to toxic metals and other abiotic stress conditions, through modulating intercellular signalling. At the end of the program the goal is to have novel, accessible tools to modify plasmodesmata in a targeted and specific manner that allow the design of strategies to mitigate the effects of climate change on plant growth, thus agricultural sustainability and food security, in a wide range of plant species including food crops such as wheat and tomato. Complementary to the fundamental work, the properties of cell walls controlling plasmodesmata will be exploited in the design of new products, such as novel biomaterials. The project, which integrates plant biomechanics, biotechnology and material engineering, has a wide range of outputs and impacts, thus offering maximal societal and economic benefits. The Fellowship will deliver crucial knowledge for the development of novel applications in the biopolymer and bioplastic sector and in crop biotechnology strengthening the UK's leading position worldwide in industrial biotechnology. Knowledge translation also addresses global priorities to ensure food security for a growing global population and to discover new resources to manufacture products with green credentials for sustainable living.

The project will generate new strategies to improve plant growth and new biomaterials derived from cell wall polymers. It will advance knowledge on plasmodesmata (PD) and unravel factors affecting PD function in coordinating responses to developmental and environmental cues. It will impact plant biotechnologists, breeders and synthetic engineers which can use the information in the design of strategies for improvement of crop growth, responses to adverse environments and to engineer the production of high value plant biopolymers. Translation of knowledge from this Fellowship will in the longer-term support growth in UK agriculture which currently produces ~60% of food needs and underpin progress on BBSRC strategic priority on 'Food security'. Increased understanding on the physics of biopolymers will reveal information for industrial application as bioplastics and biomaterials responding to RC calls for valorisation of natural resources and also to the grand challenge area 'Understanding the physics of life' and 'manufacturing the future'. In the UK alone over eight million tonnes of unused agricultural residues are generated which can be a valuable source for biopolymers. New applications for plant biopolymers will support the UK manufacturing sector which contributes £6.7 trillion to the global economy (themanufacturer.com) and support growth in the biopolymer/ bioplastic sector which is predicted to contribute £1.92 billion to the UK economy in the next decade (biomebioplastics.com). Innovations of this nature will attract considerable international interest, industrial investments and strengthen the UK's leader position in industrial biotechnology. In brief, in the short term (4 years) major beneficiaries are:
- The UK workforce, through developing highly skilled people in multidisciplinary and translational research. Interdisciplinarity at the Bioscience-Physic interface is highlighted as strategically important and vulnerable area in the latest BBSRC/MRC report. The project targets this skill area, increasing the employability of the staff involved and their transferrable skills.
- The UK economy and international industrial scientific community by identifying new factors affecting plant growth and new biopolymers for novel biomaterials. UK rain fed crops, such as wheat, are at risk because the greater inter-annual variability in climate. New diseases (such as the tomato chlorosis virus) have also negative impacts on the UK economy. The project will identify new genes to target PD (a path for signaling and virus spreading) in wheat and tomato, providing new strategies for crop improvement through breeding and/or biotechnology. New biomaterials will sustain development and innovations in a variety of industries using cellulose and other plant polymers as, for example, scaffolds for tissue engineering and drug delivery, textiles and packaging products. Such advancements in plant research will provide opportunities to reduce costs and environmental damage (carbon footprint) associated with biomaterial production (e.g. by enabling use of agricultural waste).
- Policy influencers (e.g. public bodies within DEFRA) by gathering evidence on gene editing (relevant on the GMO agenda) and its impact on crop improvement and biomaterial design. The project will deliver new applications for 'rare' plant polymers which may be relevant in the context of government research priorities and funding to promote innovations in, for example, bioplastic research.
- The general public through greater understanding of plant structural biology and biomechanics and on the importance of plant cell walls for providing sustainable food and natural products. In the long term the global population will benefit from the research as it will support innovations on key food crops (e.g. wheat and tomato) addressing concerns on food security and the development of plant-biomaterials that are biodegradable and more environmentally sustainable.