Regulator t cells Signal 1 activates tyrosine kinase Adds phosphate groups to tyrosine in proteins Enzyme phospholipase cvi cleaves phosphatidyl inositol bisphosphate in T cell helper membrane Two cleavage products; two pathways First diacyl glycerol activates protein kinase C Protein kinase C moves into nucleus catalyzes formation protein complex aP1 BIOL 533 17 Lecture 7BIOL 533 17 Lecture 7 Regulator T Cells • Signal 1 activates tyrosine kinase – Adds phosphate groups to tyrosine in proteins • Enzyme phospholipase CI cleaves phosphatidyl inositol bisphosphate in T cell helper membrane • Two cleavage products; two pathways – First diacyl glycerol activates protein kinase C • Protein kinase C moves into nucleus catalyzes formation protein complex AP1