A unique phosphorylation-dependent mechanism for the activation of Ca2+/calmodulin-dependent protein kinase type IV/GR
The activity of the Ca 2+/calmodulin-dependent protein kinase IV/Gr (CaMKIV/Gr) is shown
to be strictly regulated by phosphorylation of three residues both in vitro and in response to
antigen receptor-mediated signaling in lymphocytes. One residue, Thr-200, is indispensable
for enhancement of Ca 2+/calmodulin-dependent basal activity by CaMKIV/Gr kinase. This
event requires Ca 2+/calmodulin in the full-length CaMKIV/Gr but is Ca 2+/calmodulin-
independent when a truncated version of CaMKIV/Gr is used as a substrate (ΔCaMKIV/Gr 1 …
to be strictly regulated by phosphorylation of three residues both in vitro and in response to
antigen receptor-mediated signaling in lymphocytes. One residue, Thr-200, is indispensable
for enhancement of Ca 2+/calmodulin-dependent basal activity by CaMKIV/Gr kinase. This
event requires Ca 2+/calmodulin in the full-length CaMKIV/Gr but is Ca 2+/calmodulin-
independent when a truncated version of CaMKIV/Gr is used as a substrate (ΔCaMKIV/Gr 1 …
