Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1993-11-18
pubmed:abstractText
Secreted forms of the sialoglycoprotein designated cellular prion protein (PrPC) have been identified that cannot be explained by alternative splicing. We report that secreted forms of PrPC derive from precursors that are bound to the plasma membrane by glycoinositol phospholipid (GPI) anchors. Secreted PrPC slowly appeared in the culture medium of metabolically radiolabelled cells after incubations of 8-24 h. Digestion of nascent PrPC with phosphatidylinositol-specific phospholipase C (PIPLC) prevented the appearance of secreted PrPC. Secreted PrPC partitioned into the aqueous phase of Triton X-114 like PrpC-released PrPC. While the M(r) of PIPLC-released PrPC was reduced 2-4 kDa after treatment with aqueous hydroflouric acid, which removes the entire GPI anchor modification, the M(r) of secreted PrPC was unchanged. Both PIPLC-released and secreted PrPC were recognized by antiserum raised against a synthetic C-terminal peptide corresponding to residues 220-233 (amino acid 231 is the site of GPI attachment). We conclude that GPI-anchored PrPC is post-translationally processed to remove most, if not all, of the GPI modification and then shed into culture medium. Whether PrPC is shed after proteolysis near the C-terminus remains to be established. A minority of PrPC in normal Syrian hamster brain partitioned into the aqueous phase of Triton X-114 like shed PrPC, suggesting physiological significance.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0959-6658
pubmed:author
pubmed:issnType
Print
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
319-29
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:7691278-Amino Acid Sequence, pubmed-meshheading:7691278-Animals, pubmed-meshheading:7691278-Animals, Newborn, pubmed-meshheading:7691278-Brain, pubmed-meshheading:7691278-CHO Cells, pubmed-meshheading:7691278-Cells, Cultured, pubmed-meshheading:7691278-Cricetinae, pubmed-meshheading:7691278-Epitopes, pubmed-meshheading:7691278-Glycolipids, pubmed-meshheading:7691278-Mesocricetus, pubmed-meshheading:7691278-Models, Chemical, pubmed-meshheading:7691278-Molecular Sequence Data, pubmed-meshheading:7691278-Peptide Fragments, pubmed-meshheading:7691278-Phosphatidylinositols, pubmed-meshheading:7691278-PrPSc Proteins, pubmed-meshheading:7691278-Prions, pubmed-meshheading:7691278-Protein Processing, Post-Translational, pubmed-meshheading:7691278-Structure-Activity Relationship, pubmed-meshheading:7691278-Trypsin
pubmed:year
1993
pubmed:articleTitle
Release of the cellular prion protein from cultured cells after loss of its glycoinositol phospholipid anchor.
pubmed:affiliation
Department of Neurology, University of California, San Francisco 94143.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't