Regulation of (1,3;1,4)-beta-glucan synthesis in the grasses

Lead Research Organisation: The James Hutton Institute
Department Name: Cell & Molecular Sciences

Abstract

Non-cellulosic polysaccharides from cereal grain cell walls are not digested by enzymes in the human small intestine and so contribute to total dietary fibre intake, which has been shown to reduce the risk of serious human health conditions such as colorectal cancer, cardiovascular disease and type II diabetes. The effectiveness of these non-cellulosic cell wall polysaccharides, and in particular a specific class called the (1,3;1,4)-B-glucans (or B-glucans for short), in improving health outcomes is related to their levels in grain, to their fine structure and to their associated physicochemical properties. We have previously shown that barley B-glucans are synthesized by members of the CELLULOSE SYNTHASE-LIKE F and CELLULOSE SYNTHASE LIKE-H gene families (CslF and CslH). Allelic variation at individual members of these gene families (i.e. different versions of the same genes) and/or the genes that control where and when they are switched on and off and at what level, both directly or indirectly control their relative abundance and composition (e.g. molecular size) in both the grain and the rest of the plant. Indeed variation in B-glucan content is precisely what we have observed in different barley cultivars: we have shown that different varieties contain different amounts of B-glucans and that the levels observed are under both genetic and environmental control. Some 'extreme' barley varieties contain more than 30% total fibre (cf. 3.5% in brown rice, 7% in corn, 10% in oats and 12% in wheat) and have been marketed as health promoting super-foods (e.g. Sustagrain in the USA and BarleyMax in Australia). An interesting feature of these varieties is that they contain mutations in components of the starch biosynthetic pathway, suggesting a regulatory link between starch and B-glucan metabolism and accumulation. In this project we want to investigate precisely how individual members of the CELLULOSE SYNTHASE super-family, and in particular CslF and CslH gene family members, are regulated, paying particular attention to those that are switched on in the grain during grain development. The results will have important applications in barley breeding programs where low B-glucan is important for the feed, malting and distilling industries and the opposite, namely high B- glucan, is desirable in the context of human health. The likelihood of being able to exploit the knowledge we will gain about these gene families for future product development is therefore high (e.g. as a cholesterol lowering 'health superfood', as replacement thickening agents or novel food product development such as additives/replacements to wheat based flours).

Technical Summary

The overall aim of this project is to define the regulation and functional diversity of gene families that mediate the synthesis of plant cell wall polysaccharides, in particular the (1,3;1,4)-B-glucans, that are found in walls of commercially important grasses and cereals of the Poaceae. These are important because they contribute to total dietary fibre intake and have been shown to reduce the impact of serious human health conditions such as colorectal cancer, cardiovascular disease and type II diabetes. In addition, they have many potential uses in food and novel product development. (1,3;1,4)-B-Glucans are synthesised by members of the CELLULOSE SYNTHASE-LIKE (Csl) F and H subfamilies of the CELLULOSE SYNTHASE superfamily. This superfamily in rice and other cereals contains at least 46 members, with CslF genes usually numbering less than 12 and CslH genes less than four. We will use a combination of new and recently collected data to: characterise the CELLULOSE SYNTHASE super-family in cultivated barley, determine where and when each gene is expressed during barley development, examine the regulatory processes (transcriptional and post-transcriptional) that lead to variation in their abundance and activity, investigate the role of the genetic and metabolic relationships between (1,3;1,4)-B-glucan and starch synthesis, and define the genetic and enzymic determinants of (1,3;1,4)-B-glucan fine structure that affect physicochemical properties and potential end-uses. We will integrate the data in a genetic framework that will promote knowledge exchange, stimulate end-user pull and provide a mechanism for rapid exploitation by plant breeders. We will access state of the art genomics information, and employ informatics, molecular physiology, biochemistry, RNA-biology and genetics expertise in an integrated multi-disiplinary research program building on existing and highly productive interactions between large complementary groups in the UK and Australia.

Planned Impact

Who will benefit from this research?
The Triticeae cereals are a dominant component of European agriculture and barley, as a simple diploid, is a model for genomics-assisted molecular breeding. Making the assumption that understanding and being able to manipulate soluble fibre content in barley and related cereal grains will, in the longer term, lead to novel uses in the food and health sectors we believe there will be an opportunity for commercial breeding organisations and farmers to benefit from the provision of new and higher value products. While the low B-glucan malting and distilling sectors need to be maintained, they comprise only a minor use of the crop, ~85% of which is currently used as relatively low value animal feed. Providing the opportunity to produce a higher value commodity would increase farmers' and breeders' returns on investment and benefit the whole sector. SMEs focused on the extraction and use of B-glucan in the food and health sectors may ultimately emerge.

How will they benefit from this research?
Breeders will benefit from royalties paid on higher value products. Farmers will benefit from being able to produce and sell a novel high value product with no additional investment, at a premium. Retailers will benefit from branding their produce 'healthy' and selling at a premium. Consumers will benefit from boosting their intake of natural fibre, offsetting the adverse social and personal impact of several serious human health conditions. The health sector could benefit from lower demand for their services and the tax payer could benefit from offsetting the costs of medical care.

What will be done to ensure that they have the opportunity to benefit from this research?
The conduit through which almost all genetic advances in crop production must pass to release their benefits to the broader community is the plant breeding / biotech sector. Translational activities from basic science to application are therefore crucial. The UK boasts one of the most efficient and successful commercial cereal breeding sectors in Europe and the PI maintains long lasting, strong and, importantly, funded collaborations with the majority of UK breeding companies. He has proactively engaged this community, through contacts with levy boards (farmers), maltsters, distillers, and to a certain extent the milling industry, and will continue to do so in the context of the aims and outcomes of this proposal. The team of PIs have links to the academic sector and each has a strong reputation and identity within the global community. A key distinguishing feature of this project is the international collaboration and the added value through the participation of the ARC Centre of Excellence in Plant Cell Walls in Adelaide, Australia and its Director, Professor Geoff Fincher, who has many years experience in researching barley cell-wall structure and function. Combined, the PIs have the relevant expertise, track record and motivation to ensure the project reaches a successful conclusion - while doing excellent science (on crops) along the way.
 
Description So far we have identified further members of the family of genes that are designated 'cellulose synthase like F'. Some of these have been shown to make beta glucan, the health providing soluble polysaccharide found in the grain of certain cereal grains (esp barley and oats). We have also shown that beta glucan content is likely to be controlled by a combination of synthesis and degradation rather than simply due to variation in the synthesis pathway per se. We have conducted a number of additional genetic studies, in particular using GWAS to identify candidate genes for Beta Glucan, ArabinoXylan, Ferulic Acid, and para Coumaric acid contents and other grain compositional traits. We have generated T0 knockouts of CslF3, 6, 9 and H using CRISPR-Cas9 and of other candidate genes possibly involved in beta glucan synthesis/breakdown. We have conducted a gene co-expression analysis of very early grain development. All completed work has been published. Some data remains to be written up for publication (e.g. work on Ferulic and para-coumaric acid)
Exploitation Route Beta glucan is of considerable interest in the functional foods area and as a food ingredient where high quantities are sought. In the brewing and distilling industries it is a problem, causing viscosity and as a result clogs filters and reduces overall processability. We think it could be taken down contrasting paths - one focussed on health, one on processing for the alcoholic beverage industry. There is considerable interest in the commercial sector. Consequently, we have submitted one BBSRC response mode application under the CROPNUT priority (Enhancing beta-glucan content and composition in cereal grains) have a new PhD student starting in October 2017 (with Wendy Russell, Rowett Institute) and more recently a collaborative 'Discovery' grant application to the Australian Research Council with colleagues in Melbourne (submitted Feb 2018). We submitted a response mode application in January 2018.
Sectors Agriculture, Food and Drink,Healthcare

 
Description We have currently published eight manuscripts from this collaborative project and have established strong links with groups in Australia who were our original collaborators on the application and throughout the period of award. Some of the work was incorporated as preliminary information into a fellowship application submitted by Kelly Houston in 2016. Several Talks and presentations have been given by both Dr. Houston and Prof. Waugh and a range of public engagement activities have been conducted. We have progressed our research into the control of Beta Glucan breakdown (as opposed to synthesis) as we believe this may have a strong bearing on final concentrations in the grain. We applied for funding from the BBSRC CROPNUT initiative in a new collaborative effort with RRES, but despite good reviews, sadly it was not funded. Further manuscripts have been published that are the result of this award. A further grant application has been submitted to BBSRC Response mode in January 2018 and a collaborative Australian Research Council Discovery project application submitted in parallel (January 2018).
First Year Of Impact 2014
Sector Agriculture, Food and Drink,Energy,Healthcare
Impact Types Economic

 
Description UUKI Rutherford fund - strategic partner grants
Amount £150,000 (GBP)
Funding ID RF-2018-30 
Organisation Universities UK 
Sector Academic/University
Country United Kingdom
Start 03/2018 
End 03/2019
 
Title Barseed 
Description Co-expression gene network models from early barley grain development 
Type Of Material Database/Collection of data 
Year Produced 2015 
Provided To Others? Yes  
Impact Just released 
URL https://ics.hutton.ac.uk/barseed/index.html
 
Description Barley Away Days 
Organisation University of Adelaide
Department School of Agriculture, Food and Wine
Country Australia 
Sector Academic/University 
PI Contribution We Hosted Prof Rachel Burton at our Barley Away Days in Dunkeld (3 day meeting) where she gave a talk about her latest research
Collaborator Contribution Rachel attended the BAD and interacted with students and postdocs. She gave an excellent presentation of current research in her group and judged the poster competition and short talks.
Impact Strengthened relationships with the cell walls group in Adelaide
Start Year 2017
 
Description CSLF activity 
Organisation University of Adelaide
Department School of Agriculture, Food and Wine
Country Australia 
Sector Academic/University 
PI Contribution Miriam Schreiber visited Adelaide for 2 months to test the activity of three new CslF genes she identified in the released barley genome assembly
Collaborator Contribution Hosted Miriam and taught her how to do transient assays in nicotiana and how to assay for mixed linkage beta glucan
Impact Outputs listed as Schreiber et al under BB/J014869/1 outputs
Start Year 2014
 
Description Cell Walls 2 
Organisation University of Adelaide
Department School of Agriculture, Food and Wine
Country Australia 
Sector Academic/University 
PI Contribution Kelly Houston spent 1 month in Adelaide completing work for a paper, interacting with joint students and planning further collaborative research
Collaborator Contribution Rachel Burton and Matt Tucker hosted Kelly Houston in Adelaide and worked on completing work for a paper, interacting with joint students and planning further collaborative research.
Impact paper outputs are listed under the submission for BB/J014869/1
Start Year 2014
 
Description Cell walls 1 
Organisation University of Adelaide
Department School of Agriculture, Food and Wine
Country Australia 
Sector Academic/University 
PI Contribution Kelly Houston spent 3 months in Adelaide in 2015 and 1 month in 2017. The visits allowed us to extend collaborative work on barley plant cell walls. New Joint Student between Kelly Houston (Dundee) and Matt Tucker/Rachel Burton (Adelaide) has recently been awarded.
Collaborator Contribution Hosted Kelly, gave access to all research facilities and resources, Jointly formulated PhD position, shared materials for joint publications
Impact We have published many joint papers listed under outputs of BB/J014869/1. We have collaborative grants currently under consideration in both UK (BBSRC) and Australia (ARC)
Start Year 2015
 
Description Centre of Excellence 
Organisation University of Melbourne
Department The Peter Cook Centre for Carbon Capture and Storage Research
Country Australia 
Sector Academic/University 
PI Contribution RW visited the Annual Cell Walls Conference in Hahndorf, gave a talk and planned joint research proposal for ARC.
Collaborator Contribution Joint sharing of unpublished data, writing ARC grant application with Houston and Waugh as Co-I's
Impact Grant submitted to ARC in Feb 2017
Start Year 2016
 
Description Exploiting synergies 
Organisation University of Adelaide
Department School of Agriculture, Food and Wine
Country Australia 
Sector Academic/University 
PI Contribution I jointly wrote a grant with Peter Langridge to ARC as a Co-Investigator. It was funded this year but has not yet started. We did this remotely and during face to face meetings in both Adelaide (funding for me by this award) and Europe (funding for Langridge from Adelaide)
Collaborator Contribution We jointly conceived and wrote the applicatioin
Impact A AU$570,000 ARC Grant to look at aspects of meiosis and recombination in wheat and barley
Start Year 2016
 
Description Network analysis 
Organisation University of Adelaide
Department School of Agriculture, Food and Wine
Country Australia 
Sector Academic/University 
PI Contribution Collaboration was to develop an understanding of gene networks involved in very early grain development - with a particular focus on the cellularisation of the barley endosperm. We did microarray and network analysis
Collaborator Contribution Provision of v. early cellular material, validation (qPCR) and biological interpretation of cellular networks, particularly in relation to the newly forming cell wall.
Impact Nice paper in Plant Physiology http://www.plantphysiol.org/content/170/3/1549.full.pdf
Start Year 2014
 
Description Phylogeny 
Organisation University of Adelaide
Department School of Agriculture, Food and Wine
Country Australia 
Sector Academic/University 
PI Contribution We trained and assisted Julian Schwerdt from Adelaide on Phylogenetic analysis
Collaborator Contribution Julian made several visits to Dundee where he worked with Houston, Marshall, Wright and Waugh on establishing robust sequence based molecular phylogenies
Impact http://www.plantphysiol.org/content/early/2015/05/21/pp.15.00140 Paper published from outcome of collaboration
Start Year 2014
 
Description Student Placement 
Organisation University of Adelaide
Department School of Agriculture, Food and Wine
Country Australia 
Sector Academic/University 
PI Contribution Joint PhD student Guillermo Giminez spent 3 months working in the group of Matt Tucker in the cell walls centre of excellence building reported gene constructs for transformation and testing them in vivo
Collaborator Contribution Direct supervision of Guillermo in building reported gene constructs for transformation and how to test them in vivo
Impact Guillermo is still pursuing his PhD. Publications are planned but not yet written.
Start Year 2014
 
Description ARC CoE visit 
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 • Hosted a PhD student from the ARC CoE PCW for 1 month, October 2014.
• Spent 2 Months at the Adelaide node of the ARC CoE PCW, August- October 2014.
• Spent 2 Months at the Adelaide node of the ARC CoE PCW, April- June 2013.
Year(s) Of Engagement Activity 2013,2014
 
Description Away days 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Postgraduate students
Results and Impact Transcriptional Regulation of (1,3;1,4)-ß-Glucan Synthesis in Barley. Barley Away Days (Birnam, Scotland, UK). 11th- 12th February 2016.
Year(s) Of Engagement Activity 2016
 
Description BBC Scotland 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Interview with BBC Scotland about Barley Research
Year(s) Of Engagement Activity 2015
 
Description Carlsberg 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Invited Seminar • Carlsberg research laboratory, Copenhagen, October 2015. A genetic approach to understanding the plant cell wall in barley.
Year(s) Of Engagement Activity 2015
 
Description Carlsberg II 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact • Carlsberg Symposium, Plenary Speaker, Copenhagen October 2014
Year(s) Of Engagement Activity 2014
 
Description Eucarpia Cereals Section 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact • Eucarpia Cereals Section Conference, Werningerode, June 2014 (session organiser and chair
Year(s) Of Engagement Activity 2014
 
Description Fascination of Plants and Family Fun Day 
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 EPSO's Fascination of Plants day in Dundee is combined with an event called Family fun day that we run annually at the Botanic Gardens. It has a wide range of events - including plant sales from 'friends of the gardens', displays, activities, games, educational events (e.g. the genetics garden) and other activities.
Year(s) Of Engagement Activity 2013,2014,2015,2016
 
Description FoP day 
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 Kelly Houston and Guillermo Garcia: Fascination of Plants Day. Dundee Botanic Gardens (Dundee, UK). May 2015.
Year(s) Of Engagement Activity 2015
 
Description IBGS talk 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Kelly Houston - International Barley Genetics Symposium, July 2016, Minneapolis- Podium presentation: Breaking down the (Plant Cell ) walls.
Year(s) Of Engagement Activity 2016
 
Description ITMI 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact • International Triticeae Mapping Initiative Conference Fargo, June 2012(session organiser and chair)
Year(s) Of Engagement Activity 2012
 
Description Internal seminar 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact Transcriptional Regulation of (1,3;1,4)-ß-Glucan Synthesis in Barley. Internal Seminar at The James Hutton Institute (Scotland, UK). 30th March 2016
Year(s) Of Engagement Activity 2016
 
Description Landward 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Media (as a channel to the public)
Results and Impact Interview on BBC Landward program about new breeding technologies in relation to barley and potatoes
Year(s) Of Engagement Activity 2015
 
Description Monogram 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Talk at Monogram, University of Reading, March 2014. Identifying loci associated with grain (1,3;1,4)-ß-D-glucan content; a GWAS approach.
Year(s) Of Engagement Activity 2014
 
Description Monogram talk 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Kelly Houston - Monogram, April 2016, Cambridge - Breaking down the wall- genome editing to validate genes putatively contributing to grain (1,3;1,4)-ß-glucan content.
Year(s) Of Engagement Activity 2016
 
Description Palm Cove 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Conference talk at The 5th International Conference on Plant Cell Wall Biology, Palm Cove, Queensland, July 2014. Identifying loci associated with grain (1,3;1,4)-ß-D-glucan content; a GWAS approach.
Year(s) Of Engagement Activity 2014
 
Description PhD event 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact Regulation of (1,3;1,4)-ß-Glucan Synthesis in Barley. PhD Annual Event at The James Hutton Institute (Scotland, UK). March 2016
Year(s) Of Engagement Activity 2016
 
Description Poster 1 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Transcriptional Regulation of (1,3;1,4)-ß-Glucan Synthesis in Barley. EPSO/FESPB Plant Biology Europe (Prague, Czech Republic). 26th May - 30th June 2016.
Year(s) Of Engagement Activity 2016
 
Description Poster 2 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Transcriptional Regulation of (1,3;1,4)-ß-Glucan Synthesis in Barley. ARC CoE Plant Cell Walls Retreat (Adelaide, Australia). 3rd - 4th November 2015.
Year(s) Of Engagement Activity 2015
 
Description Poster 3 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Regulation of (1,3;1,4)-ß-Glucan Synthesis in Barley. MonoGram (Rothamsted, UK). April 29th - May 1st, 2015.
Year(s) Of Engagement Activity 2015
 
Description Public engagement 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Open day at the botanic gardenss with displays, activities, demonstrations etc.
Year(s) Of Engagement Activity 2014,2015,2016
 
Description Rank Prize symposium 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Research Seminar • Rank Prize Mini-symposium on Cereal Genomics to Address Grand Challenges, May 2015.
Year(s) Of Engagement Activity 2015
 
Description Research Seminar 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Talk informed business managers, marketing experts and company execs about the science behind the commodity their business is built on. Sparked lots of discussion.

Discussed common research themes and possible interactions in future.
Year(s) Of Engagement Activity 2014
 
Description Translational cereal genomics (Vienna) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Research talk at Translational Cereal Genomics, Vienna, February 2014. Identifying loci associated with grain (1,3;1,4)-ß-D-glucan content; a GWAS approach
Year(s) Of Engagement Activity 2014
 
Description Women in Science Festival 
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 Participated in Science in the Overgate shopping centre in Dundee, Scotlands Women in Science Festival, March 2013
Year(s) Of Engagement Activity 2013
 
Description newcastle seminar 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Postgraduate students
Results and Impact Research seminar • School of Biology, University of Newcastle, October 2013. Mechanisms, Mutants, and Mapping
Year(s) Of Engagement Activity 2015