The complex structures of arabinogalactan-proteins and the journey towards understanding function.
Arabinogalactan-proteins (AGPs) are a family of complex proteoglycans found in all higher plants. Although the precise function(s) of any single AGP is unknown, they are implicated in diverse developmental roles such as differentiation, cell-cell recognition, embryogenesis and programmed cell death. DNA sequencing projects have made possible the identification of the genes encoding a large number of putative AGP protein backbones. In contrast, our understanding of how AGPs undergo extensive post-translational modification is poor and it is important to understand these processes since they are likely to be critical for AGP function. Genes believed to be responsible for post-translational modification of an AGP protein backbone, include prolyl hydroxylases, glycosyl transferases, proteases and glycosylphosphatidylinositol-anchor synthesising enzymes. Here we examine models for proteoglycan function in animals and yeast to highlight possible strategies for determining the function(s) of individual AGPs in plants.
Gaspar
Y
Y
Plant Cell Biology Research Centre, University of Melbourne, Australia.
Johnson
K L
KL
McKenna
J A
JA
Bacic
A
A
Schultz
C J
CJ
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism; D006031:Glycosylation; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D008969:Molecular Sequence Data; D009088:Mucoproteins / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D017261:Glycosylphosphatidylinositols; D009088:Mucoproteins; D010940:Plant Proteins; C006619:arabinogalactan proteins