Glycosyltransferases for O-linked Plant Arabinogalactans

Plant cell walls are important for both growth and stability, embodying a delicate balance of flexibility and rigidity. Harnessing the potential of plant cell walls as sustainable resources has long been a goal of scientific inquiry. To unlock their full potential, a deeper understanding of plant cell walls and its components is required. In this FWF funded project, led by Dr. Colin Ruprecht from the University of Natural Resources and Life Sciences (BOKU), the research team will delve into the biosynthesis and function of arabinogalactan proteins (AGPs), key players in plant cell wall architecture. AGPs, anchored to the plasma membrane, are decorated with complex O-linked type II arabinogalactan (AG-II) polysaccharides, yet their precise role in cell wall properties has remained elusive. Especially the physiological function of the AG-II glycan is still enigmatic. By employing an innovative biochemical approach, the team aims at identifying and characterizing novel glycosyltransferases (GTs) involved in AG-II biosynthesis. Through heterologous expression in human embryonic kidney (HEK) cells and leveraging a cutting- edge glycan microarray platform, the researchers will be able to perform high-throughput screening of GT activities towards more than 100 substrates simultaneously. The research extends beyond biochemical analyses, with the team also conducting in planta experiments using Arabidopsis mutants deficient in corresponding glycosyltransferase genes. By correlating structural analyses of AG-II moieties with proposed functions of AGPs, the researchers aim to elucidate the biological significance of the AG-II glycan in plant development and growth. The project will offer novel insights into plant biology and provide a platform for future research endeavors. As society seeks sustainable solutions to pressing challenges, such as resource depletion and environmental degradation, the findings from this study may provide avenues to harness the potential of plant-based materials and technologies.