Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1985-5-31
pubmed:abstractText
Insertion of the alpha- and beta-subunits of amphibian epithelial Na+,K+-ATPase into pancreatic microsomes in cell-free systems was shown to be the same as into membranes of intact cells. The glycoproteic beta-subunit was observed to be cotranslationally inserted into endoplasmic reticulum membranes and to adopt a different pattern of N-linked core and terminal sugars in two different amphibian species. The beta-subunit lacks a cleavable signal sequence but quantitative membrane integration required membrane addition at the start of synthesis. Proteolysis of beta-subunit assembled in vitro indicated a cleavable cytoplasmic domain of about 2000 daltons. The catalytic 98-kilodalton alpha-subunit was also membrane-associated during its synthesis in an alkali-resistant fashion and independent of newly synthesized beta-subunit. In contrast to the beta-subunit, membrane integration of the alpha-subunit was possible as late as a time point in its synthesis which corresponded to about 1/3-1/2 of completion of the nascent chain. A small 34 kDa trypsin-resistant fragment of the alpha-subunit was produced at an early stage of synthesis both in the intact cell and in the cell-free system. These results suggest that membrane insertion of both alpha- and beta-subunit occurs during their synthesis but with a different time course.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
260
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5154-60
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Membrane insertion of alpha- and beta-subunits of Na+,K+-ATPase.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't