Regulation of cell wall synthesis and assembly in grasses

Lead Research Organisation: Aberystwyth University
Department Name: IBERS

Abstract

The composition and cross-linking of cell wall polymers determines the efficiency by which biomass can be processed to release the abundant cell wall sugars for biofuel production. A better understanding of the cell wall structure is therefore essential to optimise the energy-potential of grasses and to enable the engineering and breeding of varieties in which cell-wall composition and cross-linking is optimized for conversion. It is estimated that more than a thousand genes are involved in the synthesis and remodelling of cell walls, but only a handful of genes have been characterised. Despite the considerable interest in developing grasses as a renewable energy source, the discovery of genes involved in cell wall biogenesis in these monocots is particularly poor. To optimize the amount, composition, and structure of cell walls in grasses we are identifying some of the genes involved. Due to the available genetic tools, its close phylogenetic relationship with energy grasses including Miscanthus, and C4 photosynthesis, maize is an ideal model for the discovery of cell wall related genes and the translation of gene-function discovery to more genetically recalcitrant bioenergy crops such as Miscanthus. Differential gene expression profiles have been determined by comparing elongating and non-elongating maize internodes using maize microarrays. Key candidate genes predicted to fulfil crucial roles in cell wall biosynthesis and remodelling will be targeted for functional testing in models with the aim that results be translated into Miscanthus. New tools including the production of antibodies that specifically recognise ferulic acid dimers are also being developed (in collaboration with Prof. Paul Knox, University of Leeds and Prof. John Ralph, University of Wisconsin-Madison) as these can be used to study the temporal and spatial aspects of cell wall cross-linking mediated by ferulic acid dimers.

Publications

10 25 50

 
Description IBERS EGB researchers have built on their historical expertise in forage quality characterisation, to study the chemical composition of energy crops. This work has also involved collaboration with chemical engineers particularly at the Universities of Aston and Leeds. Wet chemistry methods for the evaluation of biomass are expensive and slow. We have therefore developed high throughput methods based on infrared spectroscopy and mass spectrometry for cell wall components including lignin, cellulose, hemicellulose, and cell wall phenolics. These methods enable the rapid phenotyping of large numbers of plants such as from the wild, breeding lines, mapping and association populations. For example by analysing samples from 5 sites in Europe, we were able to demonstrate that plant cell wall characteristics were consistent across environments.
Exploitation Route Results from the project indicate that there is the opportunity to develop Miscanthus of defined composition which will be reasonably consistent across years and environments. The matching of feedstocks to different end uses will improve overall efficiencies of conversion. The methods developed in Supergen-Bioenergy and the ISPG have been published and are informing some of the crosses made in the breeding programme at IBERS. It is also likely that in the future rapid high throughput chemotyping methods will be used in biorefineries to enable realtime monitoring and the optimisation of processes and reactions.
Sectors Agriculture, Food and Drink,Energy

 
Description Results from the project indicate that there is the opportunity to develop Miscanthus of defined composition which will be reasonably consistent across years and environments. The matching of feedstocks to different end uses will improve overall efficiencies of conversion. The methods developed in Supergen-Bioenergy and the ISPG have been published and are informing some of the crosses made in the breeding programme at IBERS. It is also likely that in the future rapid high throughput chemotyping methods will be used in biorefineries to enable realtime monitoring and the optimisation of processes and reactions.
First Year Of Impact 2008
Sector Agriculture, Food and Drink,Energy
Impact Types Societal,Economic

 
Description ADAS visit 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Other audiences
Results and Impact Presentation and discussion with representatives from ADAS as well as people from own institute on using grass as a feedstock for biorefining as well as for animal feed. Through these discussions, it is hoped that information will be conveyed to the farming community and industry.
Year(s) Of Engagement Activity 2018
 
Description BBC Wales Radio Science Cafe Programme 
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 Recorded discussion in a glasshouse growing Miscanthus

Increased awareness and programme was mentioned at subsequent interactions
Year(s) Of Engagement Activity 2009
URL http://www.bbc.co.uk/wales/radiowales/sites/sciencecafe/updates/20110809.shtml
 
Description Royal Welsh Show 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Annual displays and activities based on agriculature and environmental green issues, including on the planting of energy crops, non-food use of plants, use of grass to make ethanol and plastics. Activities sparked discussion with farmers, and public of all ages

Visit to activities at Royal Welsh Show leads to subsequent requests for information and visits to IBERS in Aberystwyth.
Year(s) Of Engagement Activity 2007,2008,2009,2010,2011,2012,2013,2014
 
Description Science Cafe talk and discussion on biofuels good or bad 
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 Talk sparked many questions and a long discussion

No immediate but subsequent reference to the engagement by some of those attending
Year(s) Of Engagement Activity 2010
URL http://www.ibers.aber.ac.uk/mailing_list/view_newsletter.asp?ID=42
 
Description Science Cafe talk and discussion on food vs fuel 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Talk sparked many questions and a long discussion afterwards.

The discussion resulted in greater understanding of the broader and deeper implications by the audience and myself.
Year(s) Of Engagement Activity 2009