Abstract

Plant cell wall polysaccharides have important roles in growth, development, and resistance to pathogens. They are also of enormous importance in industry and agriculture, being substantial components of human and animal food, and determine the yield and properties of timber, paper and pulp. Recently, there has been great interest in using the polysaccharides as a source of renewable bioenergy, for example by degrading them to monosaccharides and fermenting to ethanol. Most plant cell wall polysaccharides are synthesized in the Golgi apparatus by a largely unknown set of enzymes. We do not understand either the role of the different wall components or how they might be altered to improve their properties for the various applications. To discover proteins involved in the synthesis of these glycans and in their sorting to the plasma membrane, we have been analyzing the protein composition of the Golgi apparatus by developing new proteomics tools. We have identified putative glycosyltransferases, sugar transporters and other novel proteins in the Golgi apparatus in Arabidopsis. We prioritise the study of candidates by integrating transcriptomic and proteomic datasets to predict function. We are studying the corresponding mutant plants using our enzymatic polysaccharide profiling technique PACE , which reveals structure and quantity of oligosaccharides released by cell wall digestion. Plants with altered cell wall polysaccharides have recently been identified.

http://www.bio.cam.ac.uk/~dupree/