Linked Life Data

1371999

Source:http://linkedlifedata.com/resource/pubmed/id/1371999

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1992-4-14
pubmed:databankReference
pubmed:abstractText
When subjected to thiol reduction, purified intestinal mucins have been shown to undergo a decrease in molecular mass and to liberate a 118-kDa glycopeptide (Roberton, A. M., Mantle, M., Fahim, R. E. F., Specian, R., Bennick, A., Kawagishi, S., Sherman, P., and Forstner, J. F. (1989) Biochem. J. 261, 637-647). The latter has been called a putative "link" component because it is assumed to be important for disulfide bond-mediated mucin polymerization. Controversy exists as to whether the putative link is an integral mucin component or a separate mucin-associated glycopeptide. In the present study both NH2-terminal and internal amino acid sequences of the 118-kDa glycopeptide of rat intestinal mucin were used to generate opposing oligonucleotide primers for polymerase chain reaction. A specific 1.2-kilobase (kb) product was obtained, from which a 0.5-kb HindIII fragment was used as a probe to screen a lambda ZAP II cDNA library of rat intestine. A 2.6-kb cDNA (designated MLP 2677) was sequenced and revealed an open reading frame of 2.5 kb encoding 837 amino acids. The deduced amino acid sequence showed that the putative link peptide is equivalent to the carboxyl-terminal 689 amino acids of a larger peptide. Northern blots revealed a mRNA size of approximately 9 kb. Computer searches revealed no sequence homology with other proteins, but similarities were seen in the alignment of cysteine residues in the link and in several domains of human von Willebrand factor, as well as cysteine-rich areas of bovine and porcine submaxillary mucins and a frog skin mucin designated FIM-B.1. In keeping with earlier demonstrations of the presence of mannose in the 118-kDa glycopeptide, there were several (13) consensus sequences for attachment of N-linked oligosaccharides within the link domain. Further sequencing of MLP 2677 in a direction 5' to the codon specifying the NH2-terminal proline of the link has revealed a coding region for 148 amino acids, including a unique 75-amino acid domain rich in cysteine and proline, and a region containing 4.5-variable tandem repeats (each 11-12 amino acids) rich in serine, threonine, and proline. The presence of mucin-like tandem repeats suggests that the entire cysteine-rich link peptide represents the carboxyl-terminal region (75.5 kDa) of a mucin-like peptide (MLP). The latter is estimated to have a molecular mass of approximately 300 kDa.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
267
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5401-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
cDNA for the carboxyl-terminal region of a rat intestinal mucin-like peptide.
pubmed:affiliation
Department of Biochemistry, Hospital for Sick Children, Toronto, Ontario, Canada.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't