Back to Search
Start Over
PKCß modulates antigen receptor signaling via regulation of Btk membrane localization.
- Source :
-
EMBO Journal . 10/15/2001, Vol. 20 Issue 20, p5692-5702. 11p. - Publication Year :
- 2001
-
Abstract
- Mutations in Bruton's tyrosine kinase (Btk) result in X-linked agammaglobulinemia (XLA) in humans and X-linked immunodeficiency (xid) in mice. While targeted disruption of the protein kinase C-β (PKCβ) gene in mice results in an immunodeficiency similar to xid, the overall tyrosine phosphorylation of Btk is significantly enhanced in PKCβ-deficient B cells. We provide direct evidence that PKCβ acts as a feedback loop inhibitor of Btk activation. Inhibition of PKCβ results in a dramatic increase in B-cell receptor (BCR)-mediated Ca2+ signaling. We identified a highly conserved PKCβ serine phosphorylation site in a short linker within the Tec homology domain of Btk. Mutation of this phosphorylation site led to enhanced tyrosine phosphorylation and membrane association of Btk, and augmented BCR and Fc∊RI-mediated signaling in B and mast cells, respectively. These findings provide a novel mechanism whereby reversible translocation of Btk/Tec kinases regulates the threshold for immunoreceptor signaling and thereby modulates lymphocyte activation. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 02614189
- Volume :
- 20
- Issue :
- 20
- Database :
- Academic Search Index
- Journal :
- EMBO Journal
- Publication Type :
- Academic Journal
- Accession number :
- 12955406
- Full Text :
- https://doi.org/10.1093/emboj/20.20.5692