... protein kinase; MAPKK, mitogen-activated protein kinase kinase; MBP, myelin basic protein; OXI1, oxidativesignal-inducible 1; PDK1, 3-phosphoinositide-dependent kinase 1; PTI1, Pto-interacting ... alone. The kinase-deficient mutant,OXI1K45R, in which the lysine residue of the ATP bind-ing domain is mutated to arginine, still interacted withPTI1-4. These data indicate that the kinase activity ... PINOID. Cell 100, 469–478.12 Benjamins R, Quint A, Weijers D, Hooykaas P &Offringa R (2001) The PINOID protein kinase regulatesorgan development in Arabidopsis by enhancing polarauxin...