Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
51
pubmed:dateCreated
2007-3-6
pubmed:abstractText
Recent studies have shown that a sizable fraction of PrPSc present in prion-infected tissues is, contrary to previous conceptions, sensitive to digestion by proteinase K (PK). This finding has important implications in the context of diagnosis of prion disease, as PK has been extensively used in attempts to distinguish between PrPSc and PrPC. Even more importantly, PK-sensitive PrPSc (sPrPSc) might be essential to understand the process of conversion and aggregation of PrPC leading to infectivity. We have isolated a fraction of sPrPSc. This material was obtained by differential centrifugation at an intermediate speed of Syrian hamster PrPSc obtained through a conventional procedure based on ultracentrifugation in the presence of detergents. PK-sensitive PrPSc is completely degraded under standard conditions (50 mug/mL of proteinase K at 37 degrees C for 1 h) and can also be digested with trypsin. Centrifugation in a sucrose gradient showed sPrPSc to correspond to the lower molecular weight fractions of the continuous range of oligomers that constitute PrPSc. PK-sensitive PrPSc has the ability to convert PrPC into protease-resistant PrPSc, as assessed by the protein misfolding cyclic amplification assay (PMCA). Limited proteolysis of sPrPSc using trypsin allows for identification of regions that are particularly susceptible to digestion, i.e., are partially exposed and flexible; we have identified as such the regions around residues K110, R136, R151, K220, and R229. PK-sensitive PrPSc isolates should prove useful for structural studies to help understand fundamental issues of the molecular biology of PrPSc and in the quest to design tests to detect preclinical prion disease.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1520-4995
pubmed:author
pubmed:issnType
Electronic
pubmed:day
26
pubmed:volume
45
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
15710-7
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Isolation and characterization of a proteinase K-sensitive PrPSc fraction.
pubmed:affiliation
Prion Research Unit, Department of Medicine, School of Medicine, University of Santiago de Compostela, Rue de S. Francisco s/n, Santiago de Compostela, Galiza, Spain 15782.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural