Palmitylation of an amino-terminal cysteine motif of protein tyrosine kinases p56lck and p59fyn mediates interaction with glycosyl-phosphatidylinositol-anchored proteins.

摘要: Abstract Cross-linking of glycosyl-phosphatidylinositol (GPI)-anchored membrane proteins on T cells can trigger cell activation. We and others have shown an association between GPI-anchored the protein tyrosine kinases (PTKs) p56lck p59fyn, suggesting a pathway for signaling through proteins. Studies decay-accelerating factor (DAF) or CD59 in either C32 line HeLa transfected with PTK cDNA demonstrated that associated noncovalently p59fyn but not p60src. Nonmyristylated versions also failed to associate Mutational analysis mapped unique amino-terminal domains PTK. A chimeric consisting 10 residues replacing corresponding amino acids p60src was sufficient DAF, converse constructs containing first plus remainder did DAF. Mutation cysteine serine at positions 3 6 5 abolished these conferred ability Direct labeling [3H]palmitate palmitylation this motif p56lck. Thus, residue(s) together myristylation glycine residue defines important motifs PTKs