Plants are an ancient, rich and sustainable source of natural chemodiversity in the form of alkaloids, terpenoids, flavonoids, tannins and other classes of small-molecular-weight compounds (phytochemicals). Lacking the adaptive immunity of animals, plants evolved to rely on small molecules for their survival, proliferation and reproduction.
Department of Biochemistry and Molecular Biology
Plants are capable of producing a great diversity of relatively small organic chemicals that are called “secondary”, or, more recently, “specialized” metabolites, because they are not involved in central metabolism (Gang, 2005; Weng and Noel, 2012). Currently, well over 200,000 distinct molecules are known to be produced by plants and found to serve many important roles. As pigments, scents, and flavors they attract pollinators and seed dispersers (Gang, 2005).
Potato (Solanum tuberosum L.) is an important crop in the United States and approximately 38,000 tons were produced in Massachusetts in 2006, with a value of $7.5M (National Agricultural Statistics Service, USDA). About 92-percent of the Massachusetts crop is consumed fresh or marketed as processed products, while 8-percent is re-used as seed tubers. Tuber sprouting during storage, caused by dormancy release of tuber buds, leads to undesirable loss of weight, turgidity and texture alterations.
Unique among crop species, legumes produce their own nitrogen nutrient through a symbiosis with nitrogen-fixing bacteria collectively known as rhizobia. This nitrogen-fixing symbiosis is a complex system, and currently we know too few of the molecular players involved. This project will optimize two methods to reduce the activity of a given gene, and use these methods to screen for legume genes required for the function of the nitrogen-fixing symbiosis.