Back to Search
Start Over
Clustering of the high affinity Fc receptor for immunoglobulin G (Fc gamma RI) results in phosphorylation of its associated gamma-chain.
- Source :
-
The Journal of biological chemistry [J Biol Chem] 1994 Apr 22; Vol. 269 (16), pp. 12111-7. - Publication Year :
- 1994
-
Abstract
- We are investigating the role of gamma-chain in functions mediated by the high affinity Fc receptor for IgG (Fc gamma RI). In a previous study, we found that gamma-chain, which is a member of the family of zeta-chain proteins, associates with Fc gamma RI. Here we show that clustering of Fc gamma RI leads to a rapid and transient tyrosine phosphorylation of gamma-chain in U937 cells. The response was limited to Fc gamma RI activation, and no phosphorylation of gamma-chain was observed after cross-linking of monoclonal antibodies to other surface receptors on these cells. The gamma-chain phosphorylated after Fc gamma RI clustering was the gamma-chain associated with the receptor. We also identified Syk as one of the kinases associated with the receptor complex. Upon Fc gamma RI activation, Syk, but not ZAP-70, was phosphorylated, and reimmunoadsorption experiments of phosphoproteins from immune complex in vitro kinase assays indicated that Syk is part of the activated gamma-chain-Fc gamma RI complex. These results suggest that gamma-chain links Fc gamma RI to intracellular transduction pathways.
- Subjects :
- Adenosine Triphosphate metabolism
Antibodies, Monoclonal
Blotting, Western
Cell Line
Electrophoresis, Polyacrylamide Gel
Humans
Macromolecular Substances
Phosphorylation
Phosphotyrosine
Receptors, IgG biosynthesis
Receptors, IgG isolation & purification
Tumor Cells, Cultured
Tyrosine analysis
Tyrosine metabolism
Immunoglobulin G metabolism
Receptors, IgG metabolism
Tyrosine analogs & derivatives
Subjects
Details
- Language :
- English
- ISSN :
- 0021-9258
- Volume :
- 269
- Issue :
- 16
- Database :
- MEDLINE
- Journal :
- The Journal of biological chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 7512959