The 34 kilodalton insulin-like growth factor binding proteins in human cerebrospinal fluid and the A673 rhabdomyosarcoma cell line are human homologues of the rat BRL-3A binding protein.
Three members of a family of insulin-like growth factor binding proteins have been identified by nucleotide sequencing of cDNA clones: the binding subunit of the 150 kDa IGF-binding protein complex in human serum, the 30 kDa IGF binding protein in human amniotic fluid, and a 30 kDa binding protein (BP-3A) isolated from the rat BRL-3A cell line. The present study demonstrates by molecular hybridization and immunoreactivity that the human counterpart of rat BP-3A is a 34 kDa IGF binding protein that is present in human cerebrospinal fluid and is synthesized and secreted by the A673 human rhabdomyosarcoma cell line.
Romanus
J A
JA
Molecular, Cellular and Nutritional Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Diseases, MD 20892.
Tseng
L Y
LY
Yang
Y W
YW
Rechler
M M
MM
D000653:Amniotic Fluid / Q000378:metabolism; D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D002352:Carrier Proteins / Q000378:metabolism*; D002460:Cell Line; D004247:DNA / Q000235:genetics; D015342:DNA Probes; D004591:Electrophoresis, Polyacrylamide Gel; D005786:Gene Expression Regulation; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins; D008970:Molecular Weight; D009693:Nucleic Acid Hybridization; D051381:Rats; D012208:Rhabdomyosarcoma / Q000378:metabolism*; D012689:Sequence Homology, Nucleic Acid; D013002:Somatomedins / Q000134:cerebrospinal fluid*; D014407:Tumor Cells, Cultured / Q000378:metabolism
D002352:Carrier Proteins; D015342:DNA Probes; D018969:Insulin-Like Growth Factor Binding Proteins; D013002:Somatomedins; D004247:DNA