Improving Camelina seed oil production by modulating mucilage synthesis – CASOM

Camelina is emerging as an alternative oilseed crop due to its resistance to adverse growth conditions and the quality of its oil for nutrition or biofuel production. Camelina oil is rich in unsaturated fatty acids and in particular omega-3 fatty acids that are renowned for their health benefits. Essentially an ancient crop, relatively little selection has been carried out and there is an enormous potential for breeding and improvement. Camelina sativa is a member of the Brassicaceae family, which includes a number of economically important oilseed crops, and its agronomic attributes make it an excellent complement to their production. Nevertheless, development of the agronomic potential of Camelina is currently limited as relatively few genetic and genomic resources are available.
Increased oil contents have been achieved in Arabidopsis, a close relative of Camelina, by reducing the production of the polysaccharides that form seed mucilage through the mutation of a transcription factor. Mucilage polysaccharides are accumulated in the epidermal cells of the seed coat during seed development and these hydrophilic polymers are released during imbibition. Furthermore, mucilage polysaccharides act as emulsifiers and sequester oil, and their removal from seeds should improve extractability.
In the CASOM project we aim to increase oil production in Camelina by reducing the production of mucilage polysaccharides. This will be carried out in proof of concept studies by site-specific mutation of gene homologs for two transcription regulators identified in Arabidopsis as required for mucilage synthesis. A novel seed micropress system will be exploited to validate their effect on oil extraction. The molecular genetic characterization of one of the transcription factors, recently identified by the project partners, will also be carried out. In parallel, transcriptomic and genome wide association (GWAS) studies will be used to identify novel Camelina gene candidates that can be used to modify mucilage production and improve oil extraction. Transcriptome data will be obtained for the seed coat epidermal cells at different developmental stages and data will be filtered against transcriptomes from other plant tissues. For GWAS, sequence polymorphisms will be identified from genome resequencing data for around 200 Camelina accessions from diverse backgrounds. This data will also contribute to our characterisation of the genetic variability between Camelina. The transcriptome and genome sequence data will be made freely available to other researchers in a user friendly web resource and will thus contribute to improving the genomic resources available for future Camelina studies.
The CASOM project involves the collaboration of two international partners, one French and the other German with complementary expertise and a solid background in seed and polysaccharide research. The primary objectives of CASOM are (1) to validate that reducing mucilage production in Arabidopsis and Camelina through transcription regulators can increase oil contents and extractability and (2) to identify novel targets for the modulation of mucilage production in Camelina.