Linked Life Data

6179771

Source:http://linkedlifedata.com/resource/pubmed/id/6179771

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1982-10-29
pubmed:abstractText
The glycoprotein hormone alpha-subunit was extracted and purified from the urine of a patient with undifferentiated carcinoma producing isolated alpha-subunit. Its final specific immunoactivity was 0.92 (mg alpha-subunit/mg protein). The alpha-subunit exhibited virtually identical immunoantigenicity to hCG-alpha antiserum with standard hCG-alpha. The molecular weight of the alpha-subunit determined by gel chromatography on Sephadex G-100 was greater than that of standard hCG-alpha dissociated by urea in vitro. By SDS disc electrophoresis, however, the alpha-subunit moved faster than hCG-alpha separated by mercaptoethanol reduction. The amino acid composition of the alpha-subunit was quite similar to that of standard hCG-alpha. In the isoelectric focusing, the major components of the alpha-subunit from undifferentiated carcinoma and the alpha-subunit from urine of normal pregnant women (third trimester) were distributed over the range from pH 3.5 to 6.0, while standard hCG-alpha was distributed in the fractions ranging from pH 6.0 to 8.0. The result of a combination study in vitro indicated that both alpha-subunits from undifferentiated carcinoma and from urine of normal pregnant women did not actively combine with hCG-beta. These results suggest that the alpha-subunit secreted by undifferentiated carcinoma is virtually identical with standard hCG-alpha as the protein moiety but differs in regard to carbohydrate moiety, and also suggest that the excess of alpha-subunit, which is not associated with beta-subunit, may have undergone some intracellular modification, and consequently, the electric charge of the freely secreted alpha-subunit changes and it no longer has the ability to combine with the beta-subunit.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0013-7219
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
The characterization of alpha-subunit of glycoprotein hormone produced by undifferentiated carcinoma.
pubmed:publicationType
Journal Article, Comparative Study, Case Reports