Linked Life Data

2140053

Source:http://linkedlifedata.com/resource/pubmed/id/2140053

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1990-6-20
pubmed:abstractText
Plasma apolipoprotein(a) [apo(a)] shows considerable size heterogeneity, existing as discrete glycoprotein isoform variants that range in apparent molecular mass from approximately 400 to 800 kDa. To study the molecular basis of protein size variability, we have isolated liver RNA from individuals with different apo(a) isoforms, and identified apo(a)-specific transcripts using Northern blot analysis. Transcript sizes were shown to be variable (8.0-12 kb) and in all cases were closely correlated with protein masses (590-850 kDa) as determined from immunoblots. Thus, it is almost certain that apo(a) isoform size variation is due to allelic differences in the number of its tandemly repeated sequences of 114 amino acids that resemble kringle four of plasminogen. The high carbohydrate content of apo(a) makes true molecular weight estimations in SDS-PAGE gels difficult. However, a recombinant form of apo(a) containing 17 kringle repeats (calculated molecular mass of 250 kDa) migrates on SDS-PAGE gels only slightly below apoB-100, with an apparent molecular mass of approximately 500 kDa. Since smaller protein isoforms have been observed in the population, this suggests that plasma apo(a) isoforms contain from less than 17 to greater than 30 tandemly repeated kringle units.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
640-4
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Apolipoprotein(a) size heterogeneity is related to variable number of repeat sequences in its mRNA.
pubmed:affiliation
Department of Cardiovascular Research, Genentech, Inc., South San Francisco, California 94080.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't