Betaglycan presents ligand to the TGF beta signaling receptor.
Transforming growth factor beta (TGF beta) signals through a heteromeric protein kinase receptor that has a limited ability to bind ligand. This limitation is overcome by the action of betaglycan (TGF beta type III receptor), a separate TGF beta-binding membrane protein of previously unknown function. Betaglycan presents TGF beta directly to the kinase subunit of the signaling receptor, forming a high affinity ternary complex. Membrane betaglycan increases TGF beta binding to the signaling receptor, enhances cell responsiveness to TGF beta, and eliminates marked biological differences between TGF beta isoforms. Thus, betaglycan is a direct regulator of TGF beta access to the signaling receptors.
López-Casillas
F
F
Cell Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
Wrana
J L
JL
Massagué
J
J
D000595:Amino Acid Sequence; D001483:Base Sequence; D001667:Binding, Competitive; D002460:Cell Line; D006801:Humans; D008024:Ligands; D008565:Membrane Proteins / Q000378:metabolism*; D008954:Models, Biological; D008969:Molecular Sequence Data; D010770:Phosphotransferases / Q000378:metabolism; D011509:Proteoglycans / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D018125:Receptors, Transforming Growth Factor beta; D015398:Signal Transduction
D008024:Ligands; D008565:Membrane Proteins; D011509:Proteoglycans; D011956:Receptors, Cell Surface; D018125:Receptors, Transforming Growth Factor beta; C071736:betaglycan; D010770:Phosphotransferases