Linked Life Data

9335568

Source:http://linkedlifedata.com/resource/pubmed/id/9335568

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
42
pubmed:dateCreated
1997-11-20
pubmed:abstractText
Microsomal triglyceride transfer protein (MTP), a heterodimer of 97 kDa and protein disulfide isomerase, is required for the assembly of apolipoprotein B (apoB)-containing triglyceride-rich lipoproteins. These proteins have been shown to interact with each other during early stages of lipoprotein biosynthesis. Our studies indicated that binding between apoB and heterodimeric MTP was of high affinity (Kd 10-30 nM) due to ionic interactions. In contrast to MTP, protein disulfide isomerase alone interacted very poorly with lipoproteins, indicating the importance of the heterodimer in these bindings. Preincubation of lipoproteins with detergents enhanced their interaction with MTP. Native VLDL bound poorly to MTP, but its preincubation with Tween-20 resulted in significantly increased binding to MTP. Furthermore, binding of LDL was enhanced by preincubation with taurocholate, indicating that partial delipidation of apoB-containing lipoproteins results in increased binding to MTP. Subsequently, attempts were made to study interactions between C-terminally truncated apoB polypeptides and MTP. Binding of all the polypeptides to MTP was enhanced in the presence of taurocholate. Comparisons revealed that the binding of different apoB polypeptides to MTP was in the order of apoB18 > apoB28 > apoB42 > apoB100. These studies indicated that optimum interactions occur between apoB18 and MTP, and that the increase in apoB length beyond apoB18 has a negative effect on these interactions. Since apoB18 does not assemble triglyceride-rich lipoproteins, these studies suggest that apoB may interact with MTP before its lipidation. It is proposed that steps in lipoprotein biosynthesis may be dictated by the sequential display of different functional domains on the apoB polypeptide.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
36
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13060-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Apolipoprotein B binding to microsomal triglyceride transfer protein decreases with increases in length and lipidation: implications in lipoprotein biosynthesis.
pubmed:affiliation
Department of Pathology, Allegheny University of the Health Sciences, Philadelphia, Pennsylvania 19129, USA. Hussain@auhs.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't