Delineation of the CD28 signaling cascade was found to involve protein tyrosine kinase activity , followed by the activation of phospholipase A2 and 5-lipoxygenase .
delineation of the cd28 signaling cascade was found to involve protein tyrosine kinase activity , followed by the activation of phospholipase a2 and 5-lipoxygenase .
O O O B-protein_molecule O O O O O O B-protein_family_or_group I-protein_family_or_group I-protein_family_or_group O O O O O O O B-protein_molecule I-protein_molecule O B-protein_molecule O