Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
43
pubmed:dateCreated
2002-10-25
pubmed:abstractText
Leukocyte migration from bloodstream to tissue requires rapid, coordinated regulation of integrin-dependent adhesion and de-adhesion. In a previous study we demonstrated that inhibition of protein geranylgeranylation inhibited phorbol ester-stimulated avidity modulation of beta(1) integrin in several leukocyte cell lines. Both RhoA and Rap1 require post-translational modification by geranylgeranylation for full function. In this report we identify Rap1, not RhoA, as a critical geranylgeranylated protein mediating phorbol ester-stimulated beta(1) and beta(2) integrin-dependent adhesion of Jurkat cells. Overexpression of the Rap1-specific GTPase-activating protein, SPA-1, or inactivated form of Rap1 (N17Rap1) blocked phorbol ester-stimulated adhesion of Jurkat cells to fibronectin (alpha(4)beta(1)) and ICAM-1 (alpha(L)beta(2)). With high concentrations of fibronectin as ligand, Jurkat cells adhered spontaneously without phorbol ester stimulation. Unlike the phorbol ester-stimulated adhesion, adhesion induced by high density ligand was not dependent upon Rap1 activation or actin cytoskeleton reorganization. Thus, the "inside-out" adhesion signal induced by phorbol ester and the "outside-in" signal induced by high density ligand involve different pathways.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
40893-900
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
The GTPase Rap1 regulates phorbol 12-myristate 13-acetate-stimulated but not ligand-induced beta 1 integrin-dependent leukocyte adhesion.
pubmed:affiliation
Department of Medicine, Division of Hematology, University of Washington, Seattle, WA 98104, USA. liliu@u.washington.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't