Linked Life Data

3522569

Source:http://linkedlifedata.com/resource/pubmed/id/3522569

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1986-7-28
pubmed:abstractText
A protocol employing discontinuous sucrose gradient centrifugation was developed to prepare light mitochondrial (L) and Golgi fraction endosomes from simultaneously prepared parent L and microsomal fractions. As judged by the concentration of labeled hormone postinjection, L intermediate and heavy endosome subfractions were 40- to 175-fold purified and Golgi intermediate and heavy endosome subfractions were 30- to 45-fold purified. On electron microscopy, L endosomal fractions contained a predominance of lipoprotein-filled vesicles and were less heterogeneous than corresponding Golgi endosomal fractions. All endosomal fractions were enriched in receptors for insulin and prolactin but binding sites for the former were more broadly distributed in other subfractions than those for the latter. On Percoll gradient centrifugation, L endosomal fractions yielded one peak (rho 1.057) corresponding to the heavier of two peaks seen in Golgi endosomal fractions. The protein composition of high density L and Golgi endosomes, as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was similar. The bulk of marker enzymes assayed did not migrate with the endosomal components. Combined acid phosphatase cytochemistry and electron microscope radioautography established that about 80% of the L endosomes contained no acid phosphatase. By affinity labeling and immunological titration with insulin receptor antibody, insulin receptors were identical in L and Golgi endosomes. Insulin-stimulable receptor kinase was demonstrable in both L and Golgi endosome fractions. Following in vivo insulin administration, the insulin receptor kinase in both L and Golgi endosomes was significantly activated. This activated state was not inhibited by a large excess of antiserum to insulin and thus not due to insulin contaminating the partially purified receptor preparation. These observations are compatible with the maintenance and/or initiation of hormone-dependent phosphorylations intracellularly.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
261
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8462-72
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Characterization of rat liver endosomal fractions. In vivo activation of insulin-stimulable receptor kinase in these structures.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't