Understanding plant cell wall structure

Ohio University, Athens OH

Investigators

Abstract

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Plant growth depends crucially on the action of glycosyltransferase enzymes designed to build an extracellular cell wall matrix around plant cells. Yet we lack a comprehensive description of these enzymes and how they construct such an intricate supramolecular structure which is important to plant biology and industry, particularly agriculture, forestry, and renewable energy. The U.S. is capable of producing substantial amounts of biofuel in the form of ethanol by microbial fermentation of plant cell wall material; however, optimization of these procedures will require a deep understanding of the synthesis of cell wall components. Arabinogalactan-proteins (AGPs) are one such component; they are highly glycosylated hydroxyproline-rich glycoproteins. AGPs are implicated in many physiological processes including plant somatic embryogenesis, programmed cell death, wound responses, and hormone signaling pathways. Identifying AGP glycosyltransferase genes will facilitate crop improvement and plant-breeding programs. However, no AGP glycosyltransferase genes have been identified. The objective of this proposal is to identify and analyze the function of AGP-galactosyltransferase (AGP-GalT) genes involved in the first steps of AGP O-linked glycosylation. The approach builds upon an AGP-GalT assay we developed, which will enable purification and testing of candidate AGP GalTs. This project will lead to an understanding of cell wall biosynthesis and biomass growth to meet needs of the wood, paper, textile, fuel, and food industries. It will also allow for designing new AGP-based bioproducts including benign non-antigenic drug delivery products. Finally, it will provide valuable training opportunities at the undergraduate, graduate, and postdoctoral levels to create a diverse work force that will be able to pursue these needs in the future for the benefit of the U.S. economy and the environment. The investigators believe strongly in the mission of research in science education and make every effort to incorporate research activities and current literature into their teaching mission at the university.