Please use this identifier to cite or link to this item: http://hdl.handle.net/2440/11309
Citations
Scopus Web of ScienceĀ® Altmetric
?
?
Type: Journal article
Title: Localization of an Insulin-like Growth Factor (IGF) Binding Site of Bovine IGF Binding Protein-2 Using Disulfide Mapping and Deletion Mutation Analysis of the C-terminal Domain
Author: Forbes, B.
Turner, D.
Hodge, S.
McNeil, K.
Forsberg, G.
Wallace, J.
Citation: Journal of Biological Chemistry, 1998; 273(8):4647-4652
Publisher: AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
Issue Date: 1998
ISSN: 0021-9258
1083-351X
Abstract: We have investigated which region(s) of bovine insulin-like growth factor binding protein-2 (bIGFBP-2) interact with insulin-like growth factors (IGFs) using C-terminally truncated forms of bIGFBP-2. Initially to aid in mutant design, we defined the disulfide bonding pattern of bIGFBP-2 C-terminal region using enzymatic digestion. The pattern is Cys186-Cys220, Cys231-Cys242, and Cys244-Cys265. In addition, cyanogen bromide cleavage of bIGFBP-2 revealed that the N- and C-terminal cysteine-rich domains were not linked by disulfide bonds. Taking the disulfide bonding pattern into consideration, C-terminal truncation mutants were designed and expressed in COS-1 mammalian cells. Following IGF binding assays, a region between residues 222 and 236 was identified as important in IGF binding. Specifically, mutants truncated by 14, 36, and 48 residues from the C terminus bound IGFs to the same extent as wild type (WT) bIGFBP-2. Removal of 63 residues resulted in a greatly reduced (up to 80-fold) ability to bind IGF compared with WT bIGFBP-2. Interestingly this mutant lacked the IGF-II binding preference of WT bIGFBP-2. Residues 236-270 also appeared to play a role in determining IGF binding specificity as their removal resulted in mutants with higher IGF-II binding affinity.
Keywords: Animals; Cattle; Disulfides; Trypsin; Somatomedins; Insulin-Like Growth Factor Binding Protein 2; Chromatography, High Pressure Liquid; Peptide Mapping; Mutagenesis; Sequence Deletion; Binding Sites; Amino Acid Sequence; Molecular Sequence Data
RMID: 0030004395
DOI: 10.1074/jbc.273.8.4647
Appears in Collections:Biochemistry publications

Files in This Item:
There are no files associated with this item.


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.