Title
Evidence for involvement of glycoprotein-CD45 phosphatase in reversing glycoprotein-CD3-induced microtubule-associated protein-2 kinase activity in Jurkat T-cells
UMMS Affiliation
Department of Molecular Genetics and Microbiology
Publication Date
1991-06-01
Document Type
Article
Subjects
Antigens, CD; Antigens, CD3; Antigens, CD45; Antigens, Differentiation; Antigens, Differentiation, T-Lymphocyte; Calcium; Calcium-Calmodulin-Dependent Protein Kinases; Cell Line; Enzyme Activation; Histocompatibility Antigens; Humans; Kinetics; Microtubules; Phosphoprotein Phosphatases; Phosphorylation; Phosphotyrosine; Protein Kinases; Receptors, Antigen, T-Cell; T-Lymphocytes; Tyrosine
Disciplines
Microbiology | Molecular Genetics
Abstract
Ligation of CD3/TCR on T-cells induces transient activation of lymphoid MAP-2 kinase (MAP-2K), a 43 kDa serine kinase which itself is a substrate of an unidentified tyrosine kinase (pp43). The reversibility of the MAP-2K response agrees with removal of tyrosine phosphates from pp43. Since both activity as well as tyrosine phosphorylation of MAP-2K could be prolonged by Na3VO4, a phosphotyrosine phosphatase inhibitor, we studied the effect of the common CD45 isoform, which is a member of the CD45 phosphatase family, on MAP-2K activity in vivo and in vitro. We demonstrate the ability of purified CD45 phosphatase to remove tyrosine phosphates from partially purified lymphoid MAP-2K. Utilizing the approach of heterologous receptor aggregation, we also showed that CD45 could inhibit the induction of MAP-2K activity in intact Jurkat cells during CD3 or CD3 + CD4 stimulation. We therefore suggest that this phosphatase may control the activity of lymphoid MAP-2K in vivo.
Source
Biochem J. 1991 Jun 1;276 ( Pt 2):481-5.
Journal/Book/Conference Title
The Biochemical journal
Related Resources
Repository Citation
Pollack S, Ledbetter JA, Katz R, Williams K, Akerley BJ, Franklin K, Schieven GL, Nel AE. (1991). Evidence for involvement of glycoprotein-CD45 phosphatase in reversing glycoprotein-CD3-induced microtubule-associated protein-2 kinase activity in Jurkat T-cells. Molecular Genetics and Microbiology Publications. Retrieved from https://escholarship.umassmed.edu/mgm_pp/2