Intriguing, complex and everywhere: getting to grips with arabinogalactan-proteins

Abstract

In summing up the meeting, Adrienne Clarke (University of Melbourne, Australia) described the major technical challenges, especially in the area of carbohydrate structure, which remain before we can hope to define AGPs and their functions fully. The immediate challenge is to dissect the molecules currently regarded as AGPs into functional, as well as structural subgroups, within a range of developmental contexts. The key molecules with demonstrated activities and those disrupted by Yariv reagents and hydroxyproline synthesis antagonists need to be characterized as fully as possible and connections made between the various approaches to understanding function. We need to know much more about the biosynthesis of AGPs, how their biochemistry relates to their shapes and their hydrodynamic properties at the plasma membrane surfaces and within the cell wall matrix, what they bind to and the nature of any receptors. Exciting information was presented at this meeting on a great range of molecules, systems and approaches: it is inconceivable to any one who attended the symposium that AGPs do not carry out a range of important functions in plants – the challenge is to define what these are.