Linked Life Data

11356834

Source:http://linkedlifedata.com/resource/pubmed/id/11356834

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
28
pubmed:dateCreated
2001-7-9
pubmed:abstractText
Signaling through the B cell antigen receptor (BCR) is negatively regulated by the SH2 domain-containing protein-tyrosine phosphatase SHP-1, which requires association with tyrosine-phosphorylated proteins for activation. Upon BCR ligation, SHP-1 has been shown to associate with the BCR, the cytoplasmic protein-tyrosine kinases Lyn and Syk, and the inhibitory co-receptors CD22 and CD72. How SHP-1 is activated by BCR ligation and regulates BCR signaling is, however, not fully understood. Here we demonstrate that, in the BCR-expressing myeloma line J558L mu 3, CD72 expression reduces the BCR ligation-induced phosphorylation of the BCR component Ig alpha/Ig beta and its cytoplasmic effectors Syk and SLP-65. Substrate phosphorylation was restored by expression of dominant negative mutants of SHP-1, whereas the SHP-1 mutants failed to enhance phosphorylation of the cellular substrates in the absence of CD72. This indicates that SHP-1 is efficiently activated by CD72 but not by other pathways in J558L mu m3 cells and that inhibition of SHP-1 specifically activated by CD72 reverses CD72-induced dephosphorylation of cellular substrates in these cells. Taken together, BCR-induced SHP-1 activation is likely to require inhibitory co-receptors such as CD72, and SHP-1 appears to mediate the negative regulatory effect of CD72 on BCR signaling by dephosphorylating Ig alpha/Ig beta and its downstream signaling molecules Syk and SLP-65.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
26648-55
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
SHP-1 requires inhibitory co-receptors to down-modulate B cell antigen receptor-mediated phosphorylation of cellular substrates.
pubmed:affiliation
Department of Immunology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8510, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't