Virus induced gene silencing for the study of starch metabolism

[摘要] ENGLISH ABSTRACT: Virus Induced Gene Silencing (VIGS) was optimized to allow for the study of starchmetabolism. The plastidial inorganic pyrophosphatase gene, for which a mutant hasnever been identified, was studied using VIGS and it was found to have a broad rolein this subcellular compartment. The accumulation of inorganic pyrophosphatelimited the production of starch, carotenoids, chlorophyll, and increased the plantssusceptibility to drought stress. These effects highlight the importance of this enzymein maintaining a low intraplastidial concentration of PPi providing an environmentwhich facilitates these anabolic processes. Several genes involved in starchsynthesis and degradation were also targeted with the aim of establishing a systemof multiple gene silencing for the study of metabolic pathways. One, two and threegenes were successfully silenced using this system which was validated based onpreviously published data. Interestingly, simultaneous silencing of the two isoformsof disproportionating enzyme led to a novel phenotype as a large reduction in starchinstead of the expected increase was observed.

[发布机构] Stellenbosch University