Community Research and Development Information Service - CORDIS

FP7

COMREC Report Summary

Project ID: 606956
Funded under: FP7-PEOPLE
Country: United Kingdom

Periodic Report Summary 1 - COMREC (Control of meiotic recombination: from Arabidopsis to crops)

The predicted increase in the human population combined with further industrialization is anticipated to result in the global demand for food doubling by 2050. This, in conjunction with the effects of climate change, has the result that over the next few decades sustained improvements in crop yield and resilience to biotic and abiotic stresses will be required if global Food Security is to be ensured.

Although the use of genetically modified organisms may contribute to achieving this, crop improvement remains and is likely to remain, highly dependent on harnessing the genetic variation that arises during meiosis, where the formation genetic crossovers (COs), the products of homologous recombination, create new combinations of alleles that confer new phenotypes on the next generation. This variation is exploited by plant breeders to identify improved crop varieties but there are a number of constraints that pose significant challenges for breeders in their crop improvement programmes. In particular, this approach presupposes that all gene encoding regions of each chromosome can undergo recombination. However, it is now clear that in some plant species, notably major crops such as the cereals, this is not the case and it is estimated that >30% % of their genes reside in recombinationally “cold” chromosomal regions.

As a result the plant breeder is unable to access all the potential genetic variation within these species. Also, CO frequency along chromosomes is generally low, typically 1-3 COs per chromosome and CO distribution is controlled such that they do not occur in physical proximity. This makes it difficult to exchange small chromosomal regions, such that desirable genes are often transferred together with genes that are not beneficial, necessitating a time consuming programme of backcrossing to remove the unwanted genes. That said, recent research, much of it focussed on the model plant Arabidopsis thaliana, has provided important insights into the control of meiotic recombination in plants. Although, significant gaps in our fundamental understanding of CO control remain, progress is such that it is now timely to develop novel approaches to address the challenges posed by meiotic recombination in crop species. These developments in the understanding of plant meiosis have provided the knowledge platform for establishment of the COMREC consortium.

Organized into 6 workpackages (WPs) COMREC comprises an integrated programme of research training for 13 ESRs. This is aimed at determining the factors that regulate the frequency and distribution of COs during plant meiosis and translating this knowledge to develop novel strategies for improving breeding methods in key crop species. Working alongside stakeholder breeding companies will provide the ESRs with insight into the major challenges that confront the industry over the next 5-10 years, thus enabling them to direct their research activities to best effect. COMREC has 3 scientific WPs: WP2: Influence of the chromatin landscape on CO distribution; WP3: Coordination of meiotic progression and CO control; WP4: Manipulating meiotic recombination in crops.

Since the start of COMREC WP2 has made progress towards identifying genes that influence recombination frequency, to date 9 candidate genes have been identified and are being analysed. Constructs have been made that will provide insight into the differentiation between regions of high and low recombination and how this might be manipulated. Good progress has been made in establishing a chromatin immunoprecipitation (ChIP) protocol that will allow an understanding of the properties of CO sites along tomato chromosomes.

WP3 has made significant progress in developing tools to elucidate a better understanding of the factors that control the entry into meiosis and progression through meiotic prophase I. In particular, a successful method for live imaging of Arabidopsis meiosis has been developed. The application of super-resolution microscopy is providing a more detailed insight into the role key meiotic proteins play in prophase I progression. Use of a novel construct is allowing the relative roles of the DNA strand-exchange proteins RAD51 and DMC1 to be dissected. This WP is also addressing how plants deal with whole genome duplication during polyploidization. To achieve this meiotic progression is been compared in established and de novo tetraploid A. thaliana lines and also through making use of natural variation between accessions to investigate whether this is influenced by the initial level of recombination in the diploid progenitors. How plants with holocentric centromeres, rather than the typical moncentric arrangement, have modified aspects of meiosis is being studied in relation to the SMC5/SMC6 proteins which have recently been implicated in meiotic recombination.

WP4 is focused on translational research in a number of key species. Building on previous involving consortium partners (JHI, UoB) we are investigating how a moderate elevation in growth temperature may be used to influence the CO distribution in barley such that the proportion of recombination events in the interstitial and centromere proximal regions of the chromosomes is increased. Allotriploid Brassica hybrids have been found to exhibit greatly elevated levels of recombination. A range of meiotic mutants are being used to understand the mechanistic basis of this useful phenomenon. In order to begin to manipulate recombination in tomato, protocols are being developed to use CRISPR/Cas9 gene editing technology to assess how mutation of recombination pathway genes can be used to modify CO formation in this species. In order to access the full genetic variation that is available to breeders it is highly desirable to introgress chromosomal regions from close relatives. However this can be problematical due to the homoeologous (related but not identical) chromosomes, hence we are using a bioinformatics approach to investigate this in tomato to determine the influence of the genome landscape.

Although, increasing recombination is one of the goals of COMREC, it is also beneficial to develop approaches to stabilize elite lines. In this instance we wish to minimize recombination. Building on the “reverse breeding” methodology developed by a COMREC partner (UoW) and an associate partner (Rijk Zwaan), Virus induced gene silencing is being used to assess how silencing of specific recombination pathway genes may provide a route to achieving this goal.

The ESRs have completed a number of network training activities (WP1). This included a workshop on Recombination and Plant Breeding (10th July 2014) led by WP leaders and external invited speakers. Partner 11 (UoW/PRI) hosted a Bioinformatics Workshop at Wageningen University on the 4-6th of February 2015 (TA3.1.4). Topics covered were data resources such as NCBI dbs, Ensembl, and basic tools (e.g. BLAST, InterPro, Go annotation, Staden, Emboss, Primer3). The gathering also provided an opportunity to check that the ESRs are settling well in their respective RTPs. For ESRs requiring more detailed knowledge additional training will be provided by via additional secondments to UoW-PRI.

A Workshop on Advanced Methodologies in Meiosis Research was held on 5th June 2015 (TA3.1.6), organised by UCM and coordinated by P8. This was presented by COMREC partners and invited external speakers. Topics included, ChIP-seq, CRISPR/Cas9, molecular cytogenetics in cereals and the application of EM tomography. This was followed by TA3.1.7 a Workshop on Writing Scientific Papers, Reports and Grant Proposals on 6th June 2015 (Milestone 4, Deliverable 1.6). This supplemented the generic training received by ESRs in their host institutions and was led by COMREC partners and associate partners who have extensive experience in Journal reviewing, editorial work, report writing and as members of Research Funding Bodies such as DFG and BBSRC. The grant writing workshop was led by Dr Adrian Simmonds, the Research Support Manager from the College of Life and Environmental Sciences, UoB. The ESRs have undertaken or have set-up their secondments as planned and on-going.

Dissemination (WP5) of the ESRs research activity has occurred through a number of routes. ESRs have attended 9 International Conferences (for example: EMBO Meiosis Conference 2015, Oxford and Fundación Ramon Areces International Symposium: The biology of meiosis: implications for fertility and genetic disorders 2015, Salamanca) presenting 20 posters. ESRs 2 and 5 have given invited seminars in the University of New Hampshire, Chapel Hill and Karlsruhe Institute of Technology, respectively. Dissemination and outreach to the general public during 2015 has been achieved through a number of activities. For example, the ESRs organized a hands-on science event “Junior Plant Scientist for the day” at Thinktank Birmingham Science Museum Feb 2015 (Deliverable 5.2). Over 3000 people visited the museum on the day with several hundred visiting the COMREC exhibit. The ESRs have also produced a pamphlet (Deliverable 5.3) for distribution at University open-days and school visits and in their other Marie-Curie Ambassador roles. Further details of the ESRs dissemination are available at the COMREC website.

In conclusion the project has met all its planned milestones and deliverables for the period and is on course to deliver a cohort of 13 highly trained ESRs with the skills that will enable them to make a significant contribution to sustaining our future Food Security.

More information about COMREC can be found at www.birmingham.ac.uk/comrec or by contacting the project manager Rachael Batchelor (R.A.Batchelor@bham.ac.uk).

Contact

May Chung, (Research Finance Manager)
Tel.: +441214158202
Fax: +441214146056
E-mail

Subjects

Life Sciences
Record Number: 188958 / Last updated on: 2016-09-19