Project properties

Title Reviewing candidate genes for aliphatic glucosinolate biosynthesis
Group Plant Breeding, Laboratory of
Project type thesis
Credits 24
Supervisor(s) Elma Salentijn
Examiner(s) Luisa Trindade
Contact info elma.salentijn@wur.nl; luisa.trindade@wur.nl
Begin date 2020/05/01
End date 2020/12/31
Description Crambe abyssinica is a specialty crop that produces an industrial type of seed-oil. This oil is composed of around 60% of a specific fatty acid, erucic acid (C22:1), and can be used as an industrial lubricant or as raw material for oleochemistry. Furthermore, the erucic acid fraction can be converted into other chemicals, for instance in erucamide which serves as a slip agent in plastics. The high oil content of the seeds together with the high seed yield, low- input requirements and its relative resistance to salt stress, makes crambe a promising crop for low input farming on marginal soils. Like other Brassica species, crambe produces a special type of secondary metabolites in its leaves and seeds, called glucosinolates. This can be a wanted trait, as some glucosinolates are health promoting or serve as a defence against predators. However, a high content of glucosinolates and their degradation products may also have anti-nutritional effects. In crambe, the aliphatic glucosinolate epi-progoitrin can accumulate to high concentrations in seeds (>90 �mol/g DW). After tissue damage, when myrosinase enzymes come into contact with these glucosinolates, bioactive hydrolysates are formed (e.g. isothiocyanates and nitriles) which are unhealthy and reduce the value of the protein-rich seed meal. As a result, crambe meal is not recommended as feed for pigs and poultry and can only be mixed with cattle feed up to 5%. Reducing the glucosinolate content in the seeds has therefore become an important breeding trait in seed oil-producing Brassica species, including crambe. At WUR Plant breeding, we have an EMS mutant population of crambe available in which we search for plants with mutations in genes involved in glucosinolate biosynthesis. Crambe is an allohexaploid (2n=6x=90) and therefore has basically 3 loci of a gene that usually all have to be mutated to get a full effect on the phenotype. In this project you will review scientific literature to contribute to the identification of suitable candidate genes for mutagenesis. Important factors for such candidate genes are; the size of the gene family it belongs to, the number of loci that have to be mutated to obtain a mutant phenotype, functionalization within the gene family and expected side effects (pleiotropic effects) of mutations on other traits. The literature study will be focussed on genes involved in biosynthesis and transport of aliphatic glucosinolates in Brassicaceae. Peer reviewed literature will be evaluated to select the most promising target genes. This information may be derived from QTLs for glucosinolate content, natural genetic variation, induced mutations or transgenic research.
Used skills Literature study; searching and reviewing scientific literature
Requirements PBR30306; interest in molecular aspects of plant biology