1a.Objectives (from AD-416):
The objectives of this cooperative research project are. 1)to investigate the genetic elements that control carotenoid and selenium metabolisms in plants; and. 2)to develop food crops with enhanced nutritional quality.
1b.Approach (from AD-416):
The approaches will include:. 1)to use molecular, biochemical, and genetic tools to isolate and characterize novel genes and to examine metabolites for nutritional improvement;. 2)to employ genomic and proteomic approaches to investigate global expression changes associated with altered nutritional characteristics and identify novel genes/proteins involved in the biosynthesis and accumulation of carotenoids and selenium compounds in plants; and. 3)to use plant biotechnology and breeding approaches to alter the content and/or composition of these compounds in crops.
To elucidate the network that regulates a gene that controls high carotenoid accumulation, the Or gene, we performed coimmunoprecipitation (Co-IP) experiments which looks for proteins interacting with Or, and identified some candidates as potential OR-interacting proteins. We carried out complimentary biochemical assays and confirmed that OR interacted with the phytoene synthase enzyme, which controls a limiting step in the carotenoid synthesis pathway. We show that OR controls carotenoid accumulation by increasing phytoene synthase activity through regulating its protein stability.