Characterization of synthetic hydroxyproline-rich proteoglycans with arabinogalactan protein and extensin motifs in Arabidopsis.
A series of gene constructs encoding synthetic glycomodule peptides with N-terminal signal sequences and C-terminal green fluorescent proteins were expressed in transgenic Arabidopsis (Arabidopsis thaliana) under the control of the 35S promoter. The synthetic glycomodule peptides were composed of repetitive proline-containing motifs that have been previously found to be substrates for prolyl hydroxylases and subsequent O-glycosylation of the hydroxyproline residues. All of the constructs were secreted in aerial tissues, but not in roots. The amount of hydroxylation and glycosylation of the various constructs varied depending on the tissue. Also, accumulation of the proteins exhibited a high degree of cell-type specificity within various tissues due to posttranscriptional effects. The observations reveal a high level of complexity in the synthesis, secretion, and turnover of the glycoproteins.
Estévez
José M
JM
Department of Plant Biology, Carnegie Institution, Stanford, California 94305, USA.
Kieliszewski
Marcia J
MJ
Khitrov
Natalie
N
Somerville
Chris
C
D020816:Amino Acid Motifs; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D005685:Galactans / Q000737:chemistry*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D006023:Glycoproteins / Q000737:chemistry*; D006031:Glycosylation; D006900:Hydroxylation; D006909:Hydroxyproline / Q000737:chemistry / Q000378:metabolism*; D018515:Plant Leaves / Q000166:cytology / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry*; D018517:Plant Roots / Q000166:cytology / Q000378:metabolism; D018547:Plant Stems / Q000166:cytology / Q000378:metabolism; D030821:Plants, Genetically Modified; D011499:Protein Processing, Post-Translational; D021381:Protein Transport; D011509:Proteoglycans / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D005685:Galactans; D006023:Glycoproteins; D010940:Plant Proteins; D011509:Proteoglycans; C005488:extensin protein, plant; D006909:Hydroxyproline; C005653:arabinogalactan