Joint Sino-German-Project: Functional analysis and mutagenesis of GDSL genes for breeding oilseed rape (B. napus) with higher oil content GDSL

• Applicant: Professor Dr. Christian Jung
• Subject Area: Plant Breeding and Plant Pathology
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 272344271

Rapeseed is an important field crop and the major source of plant edible oil in both China and Germany. The first Sino-German Workshop on Genetics and Biotechnology of Rapeseed took place in Hangzhou on April 3-6, 2013. During the workshop Prof. Lixi Jiang of Zhejiang University (ZJU), Prof. Christian Jung of Christian-Albrechts-University Kiel (CAU) and their coworkers discussed the cooperation to systemically clone and analyze Seed Fatty Acid Reducer (SFAR) genes in Arabidopsis and identify BnSFAR knock-out mutants in Brassica napus. To increase seed oil content, many efforts have been made on the promotion of lipid biosynthesis efficiency, but little attention has been paid on the blocking of lipid decomposition in the process of oil accumulation. SFARs are defined as GDSL-type lipase genes that are expressed in seeds. They hydrolyze triacylglycerol and reduce the accumulation of seed lipids. Preliminary studies from Prof. Jiangs group pointed at ca. 25 SFARs in Arabidopsis. The disruption of 5 genes (SFAR1 - SFAR5) resulted in significant increases of fatty acids (FA) in seeds. Moreover, the loss of function at multiple sfar loci had an additive effect on promoting seed oil production. Since Arabidopsis thaliana and oilseed rape (Brassica napus) belong to the Brassicaceae family, it is expected that they share the same regulatory mechanisms to control metabolic pathways. Therefore we reason that disruption of a BnSFAR increases seed oil production in B. napus, and pyramiding Bnsfar mutants could lead to an even higher seed oil content. Prof. Jungs group at CAU has established a rapeseed mutant population which can be easily screened by a TILLING (targeting induced local lesions in genomes) protocol. The proposed joint project aims to (1) systematically clone putative Arabidopsis SFARs and to understand their functions and regulation, (2) to identify the orthologs of 5 SFAR genes (AtSFAR1 - AtSFAR5) in B. napus and to select knock down mutants, and (3) to characterize the effect of Bnsfar mutations on seed oil content and pyramide bnsfar mutations in oilseed rape (B. napus).

• DFG Programme: Research Grants
• International Connection: China
• Partner Organisation: Chinesisch-Deutsches Zentrum für Wissenschaftsförderung Beijing
• Cooperation Partner: Professor Lixi Jiang