Linked Life Data

16294008

Source:http://linkedlifedata.com/resource/pubmed/id/16294008

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2006-1-6
pubmed:abstractText
Two distinct mitogenic modes coexist in the physiologically relevant model of primary cultures of dog thyroid epithelial cells. The differentiation-associated mitogenic stimulation by TSH and cAMP specifically requires the assembly and activation of cyclin D3-cyclin-dependent kinase (CDK)4 associated to p27(kip1), while the dedifferentiating proliferation induced by growth factors is associated with induction of cyclin D1. Here, we suggest that the related CDK "inhibitors" p21(cip1) and p27 are differentially utilized as positive CDK4 regulators in these mitogenic stimulations. p21 was induced by EGF + serum, but repressed by TSH, which, as previously shown, upregulates p27. In response to EGF + serum, p21 supported the nuclear localization, phosphorylation and pRb-kinase activity of CDK4. Unexpectedly, partly different site-specificities of pRb-kinase activity, leading to similar differences in the phosphorylation pattern of pRb in intact cells, were associated with cyclin D3-CDK4 bound to p27 in TSH-stimulated cells, or with CDK4 bound to p21 in growth factor-stimulated cells. These differences were ascribed to the predominant association of the latter complex to cyclin D1. Indeed, in different cell types and species, cyclin D1 varied from cyclin D3 by more efficiently driving the phosphorylation of pRb at sites (Ser807/811 and Thr826) required for its electrophoretic mobility shift. Therefore, different D-type cyclins could differently impact some pRb functions, which should be considered not only in the understanding of the relationships between cell cycle and differentiation expression in the distinct mitogenic modes of thyroid cells, but also in various development or differentiation models associated with dramatic switches in the expression of individual D-type cyclins.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1551-4005
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
61-70
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:16294008-Animals, pubmed-meshheading:16294008-Cells, Cultured, pubmed-meshheading:16294008-Cercopithecus aethiops, pubmed-meshheading:16294008-Cricetinae, pubmed-meshheading:16294008-Cyclin D1, pubmed-meshheading:16294008-Cyclin D3, pubmed-meshheading:16294008-Cyclin-Dependent Kinase 4, pubmed-meshheading:16294008-Cyclins, pubmed-meshheading:16294008-Dogs, pubmed-meshheading:16294008-Enzyme Activation, pubmed-meshheading:16294008-Epithelial Cells, pubmed-meshheading:16294008-Humans, pubmed-meshheading:16294008-Mitosis, pubmed-meshheading:16294008-Models, Biological, pubmed-meshheading:16294008-Phosphorylation, pubmed-meshheading:16294008-Protein Transport, pubmed-meshheading:16294008-Retinoblastoma Protein, pubmed-meshheading:16294008-Substrate Specificity, pubmed-meshheading:16294008-Thyroid Gland
pubmed:year
2006
pubmed:articleTitle
Distinct specificities of pRb phosphorylation by CDK4 activated by cyclin D1 or cyclin D3: differential involvement in the distinct mitogenic modes of thyroid epithelial cells.
pubmed:affiliation
Institute of Interdisciplinary Research, Faculté de Médecine, Université Libre de Bruxelles, Campus Erasme, Brussels, Belgium.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't