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Exclusion of CD45 Inhibits Activity of P56lck Associated with Glycolipid-enriched Membrane Domains

Overview
Journal J Cell Biol
Specialty Cell Biology
Date 1996 Dec 1
PMID 8978819
Citations 69
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Abstract

p56lck (Lck) is a lymphoid-specific Src family tyrosine kinase that is critical for T-cell development and activation. Lck is also a membrane protein, and approximately half of the membrane-associated Lck is associated with a glycolipid-enriched membrane (GEM) fraction that is resistant to solubilization by Triton X-100 (TX-100). To compare the membrane-associated Lck present in the GEM and TX-100-soluble fractions of Jurkat cells, Lck from each fraction was immunoblotted with antibody to phosphotyrosine. Lck in the GEM fraction was found to be hyperphosphorylated on tyrosine, and this correlated with a lower kinase specific activity relative to the TX-100-soluble Lck. Peptide mapping and phosphatase diagests showed that the hyperphosphorylation and lower kinase activity of GEM-associated Lck was due to phosphorylation of the regulatory COOH-terminal Tyr505. In addition, we determined that the membrane-bound tyrosine phosphatase CD45 was absent from the GEM fraction. Cells lacking CD45 showed identical phosphorylation of Lck in GEM and TX-100-soluble membranes. We propose that the GEM fraction represents a specific membrane domain present in T-cells, and that the hyperphosphorylation of tyrosine and lower kinase activity of GEM-associated Lck is due to exclusion of CD45 from these domains. Lck associated with the GEM domains may therefore consitute a reservoir of enzyme that can be readily activated.

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References
1.
Mayor S, Maxfield F . Insolubility and redistribution of GPI-anchored proteins at the cell surface after detergent treatment. Mol Biol Cell. 1995; 6(7):929-44. PMC: 301249. DOI: 10.1091/mbc.6.7.929. View

2.
Solomon K, Rudd C, Finberg R . The association between glycosylphosphatidylinositol-anchored proteins and heterotrimeric G protein alpha subunits in lymphocytes. Proc Natl Acad Sci U S A. 1996; 93(12):6053-8. PMC: 39187. DOI: 10.1073/pnas.93.12.6053. View

3.
Deckert M, Ticchioni M, Bernard A . Endocytosis of GPI-anchored proteins in human lymphocytes: role of glycolipid-based domains, actin cytoskeleton, and protein kinases. J Cell Biol. 1996; 133(4):791-9. PMC: 2120835. DOI: 10.1083/jcb.133.4.791. View

4.
Laemmli U . Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970; 227(5259):680-5. DOI: 10.1038/227680a0. View

5.
Fuerst T, Niles E, Studier F, Moss B . Eukaryotic transient-expression system based on recombinant vaccinia virus that synthesizes bacteriophage T7 RNA polymerase. Proc Natl Acad Sci U S A. 1986; 83(21):8122-6. PMC: 386879. DOI: 10.1073/pnas.83.21.8122. View