Linked Life Data

1508225

Source:http://linkedlifedata.com/resource/pubmed/id/1508225

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1992-9-24
pubmed:abstractText
Testicular androgen-binding protein (ABP) and liver sex hormone-binding globulin are encoded by the same gene. These proteins have the same primary amino acid sequences, but they differ in attached oligosaccharides; the differences are presumably due to cell-specific glycosylation mechanisms. To investigate the role of oligosaccharides in ABP/sex hormone-binding globulin subunit structure, secretion, and steroid binding, mutant rat ABP proteins were constructed that eliminated one or both of the two potential sites of asparagine (Asn)-linked glycosylation. Immunoblot analysis of wild type recombinant ABP yielded the typical heterogeneous banding pattern. Secreted ABP was composed of two protomers of M(r) 46,000 and M(r) 43,000, while cellular ABP yielded three mol wt species (M(r) 43,000, 41,000, and 39,000). Substitution of the Asn residue in either consensus sequence for Asn-linked glycosylation with an Ile residue resulted in increased mobility of the immunoreactive ABP species. These changes are consistent with the loss of an Asn-linked oligosaccharide. Substitution of both Asn residues yielded a single immunoreactive species in the medium and cell extracts that migrated as a M(r) 39,000 protein. These results demonstrate that the mol wt heterogeneity of ABP is due to differential Asn-linked glycosylation of both potential sites. All three mutant forms of ABP were secreted by the COS cells. However, the amount of immunoreactive ABP and [3H]5 alpha-dihydrotestosterone binding in the medium was lower than wild type (100%) in one of the single mutants (65%) and in the double mutant (29%). Unlike the glycosylation mutants, alteration of other residues, not involved in glycosylation, yielded cellular ABP and no detectable medium ABP.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1127-34
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
The role of asparagine-linked oligosaccharides in the subunit structure, steroid binding, and secretion of androgen-binding protein.
pubmed:affiliation
Department of Pediatrics, University of North Carolina, Chapel Hill 27599.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't