Linked Life Data

3104337

Source:http://linkedlifedata.com/resource/pubmed/id/3104337

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1987-5-6
pubmed:abstractText
We have studied the subcellular site of synthesis of the GalNAc(alpha-1-0) Ser/Thr linkage in rat liver. The specific and total activities of polypeptide:N-acetylgalactosaminyltransferase (using apomucin as exogenous acceptor) were highly enriched in membrane fractions derived from the Golgi apparatus; virtually no activity was detected in membranes from the rough and smooth endoplasmic reticulum. Vesicles of the above organelles (which were sealed and of the same membrane topographical orientation as in vivo) were able to translocate UDP-GalNAc into their lumen in an assay in vitro; the initial translocation rate into Golgi vesicles was 4-6-fold higher than that into vesicles from the rough and smooth endoplasmic reticulum. Translocation of UDP-GalNAc into Golgi vesicles was temperature dependent and saturable with an apparent Km of 8-10 microM. UDP-GalNAc labeled with different radioisotopes in the uridine and sugar was used to determine that the intact sugar nucleotide was being translocated in a reaction coupled to the exit of luminal UMP. Following translocation of UDP-GalNAc, transfer of GalNAc into endogenous macromolecular acceptors was detected in Golgi vesicles and not in those from the rough and smooth endoplasmic reticulum. The above results together with previous studies on the O-xylosylation of the linkage region of proteoglycans (Nuwayhid, N., Glaser, J.H., Johnson, J.C., Conrad, H.E., Hauser, S.C., and Hirschberg, C.B. (1986) J. Biol. Chem. 261, 12936-12941) strongly suggest that, in rat liver, the bulk of O-glycosylation reactions occur in the Golgi apparatus.
pubmed:grant
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
25
pubmed:volume
262
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4153-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Subcellular site of synthesis of the N-acetylgalactosamine (alpha 1-0) serine (or threonine) linkage in rat liver.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.