Linked Life Data

2962995

Source:http://linkedlifedata.com/resource/pubmed/id/2962995

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1988-3-7
pubmed:abstractText
C4b-binding protein, C4bp, is a regulatory factor of the complement system and is also known to be a binding protein of vitamin K-dependent coagulation factor, protein S. Whereas the C4b-binding site is known to be located in the middle part of the subunit chains of C4bp, the location and properties of protein S-binding site are uncertain. Therefore, we have examined the characteristics of the interaction between human protein S and C4bp. Proteolysis of C4bp-protein S complex with chymotrypsin yielded N-terminal-derived 48-kDa fragments of C4bp subunit chains and a C-terminal-derived 160-kDa core fragment of C4bp, to which protein S was still bound. This result suggested that the protein S-binding site is located in the core domain of C4bp. Gel filtration of guanidine-treated C4bp-protein S complex in the absence of guanidine resulted in the separation of C4bp and protein S. Binding assay with 125I-labeled protein S showed that the guanidine-treated C4bp lacked the protein S-binding activity. This result suggests that the protein S-binding site in C4bp is denatured irreversibly by guanidine treatment and therefore seems to be dependent on a specific conformation of C4bp. The C4bp-binding site of protein S was lost upon thrombin treatment, suggesting that the N-terminal thrombin-sensitive region of protein S may be related to the C4bp-binding site. Although free protein S was susceptible to chymotrypsin, leukocyte elastase, and cathepsin G, C4bp-bound protein S was found to be resistant to these proteases.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-924X
pubmed:author
pubmed:issnType
Print
pubmed:volume
102
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
599-605
pubmed:dateRevised
2007-12-19
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Characterization of the interaction between human protein S and C4b-binding protein (C4bp).
pubmed:affiliation
Department of Hygienic Chemistry, Faculty of Pharmaceutical Sciences, Hokkaido University.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't