title: Cellular receptors for type beta transforming growth factor. Ligand binding and affinity labeling in human and rodent cell lines.
abstract: Type beta transforming growth factor (beta TGF) purified from human platelets to homogeneity as judged by NH2-terminal amino acid sequence analysis has been labeled with 125I to characterize its interaction with cellular receptors. Binding of 125I-beta TGF to target cells is temperature- and time-dependent, specific, saturable, and reversible. About 1.6-1.9 X 10(4) binding sites/cell with high affinity for beta TGF (Kd = 5.6-7.8 X 10(-11) M and 9.1-14 X 10(-11) M, respectively) are found in NRK-49F and BALB/c 3T3 cells. beta TGF receptors do not appear to undergo acute down-regulation by the ligand. Specific binding of 125I-beta TGF has been observed in several human, rat, and mouse fibroblast lines and in some, but not all, tumor-derived cell lines examined. 125I-beta TGF has been cross-linked to intact cells and isolated membrane preparations using disuccinimidyl suberate. Cells and isolated membranes from human, rat, and mouse origin affinity labeled with 125I-beta TGF exhibit a major labeled species of approximately 280 kilodaltons that has the properties of high affinity and specificity expected from a physiologically relevant beta TGF receptor. Minor labeled species of 70-90 kilodaltons are also labeled by 125I-beta TGF, but they correspond to molecular species with low apparent affinity (Kd approximately 10(-8) M) for 125I-beta TGF.
authors.forename: J
authors.initials: J
authors.lastname: Massagué
authors.forename: B
authors.initials: B
authors.lastname: Like
mesh_terms: D000345:Affinity Labels / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001792:Blood Platelets / Q000032:analysis; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D066246:ErbB Receptors; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007668:Kidney / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D010455:Peptides / Q000378:metabolism*; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism*; D012995:Solubility; D013388:Succinimides / Q000494:pharmacology; D013696:Temperature; D013997:Time Factors; D015291:Transforming Growth Factors
chemical_list: D000345:Affinity Labels; D010455:Peptides; D011956:Receptors, Cell Surface; D013388:Succinimides; D015291:Transforming Growth Factors; D066246:ErbB Receptors; C019358:disuccinimidyl suberate