Receptor tyrosine phosphatase R-PTP-kappa mediates homophilic binding.
AUTOR(ES)
Sap, J
RESUMO
Receptor tyrosine phosphatases (R-PTPases) feature PTPase domains in the context of a receptor-like transmembrane topology. The R-PTPase R-PTP-kappa displays an extracellular domain composed of fibronectin type III motifs, a single immunoglobulin domain, as well as a recently defined MAM domain (Y.-P. Jiang, H. Wang, P. D'Eustachio, J.M. Musacchio, J. Schlessinger, and J. Sap, Mol. Cell. Biol. 13:2942-2951, 1993). We report here that R-PTP-kappa can mediate homophilic intercellular interaction. Inducible expression of the R-PTP-kappa protein in heterologous cells results in formation of stable cellular aggregates strictly consisting of R-PTP-kappa-expressing cells. Moreover, the purified extracellular domain of R-PTP-kappa functions as a substrate for adhesion by cells expressing R-PTP-kappa and induces aggregation of coated synthetic beads. R-PTP-kappa-mediated intercellular adhesion does not require PTPase activity or posttranslational proteolytic cleavage of the R-PTP-kappa protein and is calcium independent. The results suggest that R-PTPases may provide a link between cell-cell contact and cellular signaling events involving tyrosine phosphorylation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=358350Documentos Relacionados
- The receptor tyrosine kinase ARK mediates cell aggregation by homophilic binding.
- Cloning and characterization of R-PTP-kappa, a new member of the receptor protein tyrosine phosphatase family with a proteolytically cleaved cellular adhesion molecule-like extracellular region.
- PTP-PEST: a protein tyrosine phosphatase regulated by serine phosphorylation.
- Regulation by protein-tyrosine phosphatase PTP2 is distinct from that by PTP1 during Dictyostelium growth and development.
- Preferential oxidation of the second phosphatase domain of receptor-like PTP-α revealed by an antibody against oxidized protein tyrosine phosphatases