Cloning and expression of the growth hormone-dependent insulin-like growth factor-binding protein.
N-terminal as well as internal amino acid sequence data were obtained from the GH dependent, insulin-like growth factor (IGF) binding protein, BP-53, purified from human plasma. Based on these sequence data, full-length cDNA clones of BP-53 have been isolated, and the complete deduced sequence of BP-53 determined. This sequence contains a 27 amino acid putative signal sequence followed by a mature protein of 264 amino acids containing 18 cysteine residues clustered near the N- and C-terminus. The deduced protein sequence of BP-53 has 33% amino acid identity including conservation of all 18 cysteine residues with the recently cloned BP-28, a smaller human IGF-binding protein identified in amniotic fluid and also secreted by the cell line HEP G2. Expression of the cloned BP-53 cDNA in mammalian tissue culture cells results in secretion of the protein into the culture medium. This expressed protein is identical to plasma-derived BP-53 in its immunoreactivity, high affinity binding of IGF-I and IGF-II, and mobility on sodium dodecyl sulfate gel electrophoresis.
Wood
W I
WI
Department of Developmental Biology, Genentech, Inc., South San Francisco, California 94080.
Cachianes
G
G
Henzel
W J
WJ
Winslow
G A
GA
Spencer
S A
SA
Hellmiss
R
R
Martin
J L
JL
Baxter
R C
RC
D000595:Amino Acid Sequence; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D005786:Gene Expression Regulation; D013006:Growth Hormone / Q000494:pharmacology / Q000502:physiology*; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins; D008969:Molecular Sequence Data; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000378:metabolism; D017451:Receptors, Somatomedin
D002352:Carrier Proteins; D018969:Insulin-Like Growth Factor Binding Proteins; D011956:Receptors, Cell Surface; D017451:Receptors, Somatomedin; D013006:Growth Hormone