title: The role of glycosylation in the function of a 48-kDa glycoprotein from carrot.
abstract: Carrot extracellular dermal glycoprotein (EDGP) may play an important role in plant defense systems and in signal transduction. Our experiments show that differences in pI values of EDGP isoforms are caused by differences in amino acid sequence and not by heterogeneity in phosphorylation. The binding affinity of native EDGP for a 4-kDa hormone-like peptide from soybean was approximately one-third that of deglycosylated EDGP, and deglycosylation of EDGP caused complete loss of its ability to inhibit xyloglucan-specific endo-beta-1,4-glucanase. Experiments using tunicamycin-treated carrot cell cultures showed that glycosylation is essential for correct EDGP folding and secretion, and that tunicamycin does not affect EDGP gene transcription.
authors.affiliation: Kihara Institute for Biological Research, Graduate School of Integrated Science, Yokohama City University, Japan.
authors.forename: Chengwei
authors.initials: C
authors.lastname: Shang
authors.forename: Hidenori
authors.initials: H
authors.lastname: Sassa
authors.forename: Hisashi
authors.initials: H
authors.lastname: Hirano
mesh_terms: D002478:Cells, Cultured; D018552:Daucus carota / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D006023:Glycoproteins / Q000737:chemistry* / Q000378:metabolism*; D006031:Glycosylation; D008970:Molecular Weight; D017510:Protein Folding; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D006023:Glycoproteins; D020033:Protein Isoforms