RUI: Functional Analysis of VTC3, a Novel Regulator of Ascorbate Biosynthesis in Plants.

Suny College At Cortland, Cortland NY

Investigators

Abstract

Ascorbic acid is a small molecule that most people know as the antioxidant Vitamin C, which is a critical component of the human diet. In plants, the synthesis of ascorbic acid is a regulated process. For example, plants make little ascorbic acid in the dark and very high levels in the light in large part to detoxify oxygen free radicals produced as a by-product of photosynthesis. How such regulation is controlled is not well understood. In the model plant species Arabidopsis thaliana a gene has been identified (VTC3 for Vitamin C gene number 3) that encodes a protein likely involved in the regulation of ascorbic acid biosynthesis. The VTC3 protein contains predicted domains known to be involved in signal transduction pathways. Further, mutants lacking this protein are ascorbic acid-deficient. Given the identity of these domains, the VTC3 protein may be "dual purpose" and have a role in both the positive and negative regulation of ascorbic acid biosynthesis. This project aims to define how VTC3 is involved in this regulation via an integrated molecular genetic, biochemical, and proteomics-based approach. This approach will lead to an understanding of the biochemical activity of the VTC3 protein domains and how these domains (directly or indirectly via protein binding partners) impact the expression and/or activity of plant ascorbic acid biosynthetic enzymes, and ultimately ascorbic acid levels under differing environmental conditions. Broader Impacts: This project is certain to advance the understanding of signal transduction pathways in plants, in particular with regards to the regulation of ascorbic acid biosynthesis in plants. Applications in the field of agriculture are probable considering the role of this small molecule in the protection of plants against environmentally induced stresses. One of the strongest global impacts of this project will be the effect that it has on the undergraduates that are involved. The undergraduates and high school students working directly on this project during the semester and the summer months will gain confidence in their ability to conduct scientific research and the intellectual and hands-on tools to succeed in the rapidly advancing field of biology. A subset will benefit from a multi-week international research experience in the U.K. in the laboratory of a collaborator at the University of Exeter. On a local level, the research and educational capacities of the principal investigator's department and the college as a whole will be enhanced through the purchase of new equipment and the introduction of new technologies and techniques.