| Abstract Detail
Secondary Metabolism Gilliland, Laura UIlrich [1], Supplee, Andrea [1], Magallanes-Lundback, Maria [1], DellaPenna, Dean [1]. Utilizing QTL investigation to identify novel alleles affecting the tocopherol pathway in plants. Plants contain a variety of mechanisms to limit the production of reactive oxygen species (ROS) or to rapidly detoxify excess ROS produced and thereby limit the damage caused. In plants, tocopherols act as physiochemical stabilizers of membranes rich in polyunsaturated fatty acids, physical quenchers of singlet oxygen (1O2), chemical scavengers of ROS, and chain-breaking antioxidants during lipid oxidation. The health benefits of tocopherols as vitamin E include maintenance of healthy neurological, muscular, immune, and reproductive systems. While the core genes of the tocopherol pathway are known, our understanding of other loci that regulate the pathway or otherwise influence tocopherol levels is limited. We are utilizing the untapped genetic variation between Arabidopsis ecotypes to identify these genes. Quantitative trait loci (QTL) analysis of two recombinant inbred populations has identified several distinct QTL affecting tocopherol content and composition in seed. We are using fine mapping of near isogenic lines to find the underlying genes responsible for several of these QTL. QVE7 is responsible for altering gamma-tocopherol levels in seed and has been localized to At3g01310, a gene previously unassociated with tocopherol regulation. We are currently testing whether the biosynthetic pathway gene gamma-tocopherol methyl transferase is the underlying gene responsible for the QTL QVE3, which impacts the alpha-tocopherol level of seed. The identification of natural alleles affecting the level of these antioxidants in Arabidopsis will further our knowledge of the regulation of enzymatic pathways; and have ramifications for traditional crop breeding and metabolic engineering. Log in to add this item to your schedule
1 - Michigan State University, Biochemistry
Keywords: QTL biofortification phenylpropanoid metabolism tocopherol quantitative trait loci vitamin E seed metabolism.
Presentation Type: Plant Biology Abstract Session: P Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton Date: Sunday, July 8th, 2007 Time: 8:00 AM Number: P20011 Abstract ID:203 |