Linked Life Data

10766759

Source:http://linkedlifedata.com/resource/pubmed/id/10766759

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
2000-8-10
pubmed:abstractText
Osteopontin (OPN) is a non-collagenous, glycosylated phosphoprotein associated with biomineralization in osseous tissues, as well as ectopic calcification. We previously reported that osteopontin was co-localized with calcified deposits in atherosclerotic lesions, and that osteopontin potently inhibits calcium deposition in a human smooth muscle cell (HSMC) culture model of vascular calcification. In this report, the role of phosphorylation in osteopontin's mineralization inhibitory function was examined. The ability of OPN to inhibit calcification completely depended on post-translational modifications, since bacteria-derived recombinant OPN did not inhibit HSMC mineralization. Following casein kinase II treatment, phosphorylated OPN (P-OPN) dose-dependently inhibited calcification of HSMC cultured in vitro about as effectively as native OPN. The inhibitory effect of osteopontin depended on the extent of phosphorylation. To determine the specific structural domains of OPN important for inhibition of calcification, we compared OPN fragments (N-terminal, C-terminal, and full-length), and compared the inhibitory effect of both phosphorylated and non-phosphorylated fragments. While none of the non-phosphorylated OPN fragments effected calcification, P-OPN caused dose dependent inhibition of HSMC calcification. P-OPN was treated with alkaline phosphatase to create dephosphorylated OPN. Dephosphorylated OPN did not have an inhibitory effect on calcification. The expression of OPN mRNA and P-OPN secretion by HSMC were decreased in a time-dependent manner during culture calcification. These results indicate that phosphorylation is required for the inhibitory effect of OPN on HSMC calcification, and that regulation of OPN phosphorylation represents one way in which mineralization may be controlled by cells.
pubmed:grant
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
30
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
20197-203
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:10766759-Alkaline Phosphatase, pubmed-meshheading:10766759-Animals, pubmed-meshheading:10766759-Animals, Newborn, pubmed-meshheading:10766759-Blotting, Northern, pubmed-meshheading:10766759-Calcium, pubmed-meshheading:10766759-Casein Kinase II, pubmed-meshheading:10766759-Cells, Cultured, pubmed-meshheading:10766759-Dose-Response Relationship, Drug, pubmed-meshheading:10766759-Humans, pubmed-meshheading:10766759-Muscle, Smooth, Vascular, pubmed-meshheading:10766759-Osteopontin, pubmed-meshheading:10766759-Phosphorylation, pubmed-meshheading:10766759-Plasmids, pubmed-meshheading:10766759-Precipitin Tests, pubmed-meshheading:10766759-Protein-Serine-Threonine Kinases, pubmed-meshheading:10766759-RNA, Messenger, pubmed-meshheading:10766759-Rats, pubmed-meshheading:10766759-Recombinant Proteins, pubmed-meshheading:10766759-Sialoglycoproteins, pubmed-meshheading:10766759-Time Factors
pubmed:year
2000
pubmed:articleTitle
Phosphorylation of osteopontin is required for inhibition of vascular smooth muscle cell calcification.
pubmed:affiliation
Department of Bioengineering, University of Washington, Seattle, Washington, 98195, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't