Linked Life Data

17711859

Source:http://linkedlifedata.com/resource/pubmed/id/17711859

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
41
pubmed:dateCreated
2007-10-8
pubmed:abstractText
A key issue regarding the role of alpha6beta4 in cancer biology is the mechanism by which this integrin exerts its profound effects on intracellular signaling, including growth factor-mediated signaling. One approach is to evaluate the intrinsic signaling capacity of the unique beta4 intracellular domain in the absence of contributions from the alpha6 subunit and tetraspanins and to assess the ability of growth factor receptor signaling to cooperate with this domain. Here, we generated a chimeric receptor composed of the TrkB extracellular domain and the beta4 transmembrane and intracellular domains. Expression of this chimeric receptor in beta4-null cancer cells enabled us to assess the signaling potential of the beta4 intracellular domain alone or in response to dimerization using brain-derived neurotrophic factor, the ligand for TrkB. Dimerization of the beta4 intracellular domain results in the binding and activation of the tyrosine phosphatase SHP-2 and the activation of Src, events that also occur upon ligation of intact alpha6beta4. In contrast to alpha6beta4 signaling, however, dimerization of the chimeric receptor does not activate either Akt or Erk1/2. Growth factor stimulation induces tyrosine phosphorylation of the chimeric receptor but does not enhance its binding to SHP-2. The chimeric receptor is unable to amplify growth factor-mediated activation of Akt and Erk1/2, and growth factor-stimulated migration. Collectively, these data indicate that the beta4 intracellular domain has some intrinsic signaling potential, but it cannot mimic the full signaling capacity of alpha6beta4. These data also question the putative role of the beta4 intracellular domain as an "adaptor" for growth factor receptor signaling.
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
12
pubmed:volume
282
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
30322-30
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Intrinsic signaling functions of the beta4 integrin intracellular domain.
pubmed:affiliation
Department of Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural