Molecular cloning of a phosphatidylinositol-anchored membrane heparan sulfate proteoglycan from human lung fibroblasts.
Two mAbs raised against the 64-kD core protein of a membrane heparan sulfate proteoglycan from human lung fibroblasts also recognize a nonhydrophobic proteoglycan which accumulates in the culture medium of the cells. Pulse-chase studies suggest that the hydrophobic cell-associated forms act as precursors for the nonhydrophobic medium-released species. The core proteins of the medium-released proteoglycans are slightly smaller than those of the hydrophobic cell-associated species, but the NH2-terminal amino acid sequences of both forms are identical. The characterization of human lung fibroblast cDNAs that encode the message for these core proteins and the effect of bacterial phosphatidylinositol-specific phospholipase C suggest that the hydrophobic proteoglycan is membrane-anchored through a phospholipid tail. These data identify a novel membrane proteoglycan in human lung fibroblasts and imply that the shedding of this proteoglycan may be related to the presence of the phospholipid anchor.
David
G
G
Center for Human Genetics, University of Leuven, Belgium.
Lories
V
V
Decock
B
B
Marynen
P
P
Cassiman
J J
JJ
Van den Berghe
H
H
D000595:Amino Acid Sequence; D001483:Base Sequence; D002462:Cell Membrane / Q000378:metabolism; D011508:Chondroitin Sulfate Proteoglycans / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D003470:Culture Media; D005347:Fibroblasts; D006017:Glycolipids / Q000378:metabolism; D006031:Glycosylation; D017261:Glycosylphosphatidylinositols; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008168:Lung; D008969:Molecular Sequence Data; D010716:Phosphatidylinositols / Q000378:metabolism
D011508:Chondroitin Sulfate Proteoglycans; D003470:Culture Media; D006017:Glycolipids; D017261:Glycosylphosphatidylinositols; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate; D010716:Phosphatidylinositols