Here we show that the major plasma membrane proton pumps in Arabidopsis, AHA1 and AHA2, interact directly in vitro and in planta with PSY1R, a receptor kinase of the plasma membrane that serves as a receptor for the peptide growth hormone PSY1.  The intracellular protein kinase domain of PSY1R phosphorylates AHA2/AHA1 at Thr-881, situated in the autoinhibitory region I of the C-terminal domain.  Application of PSY1 to plant seedlings induced rapid in planta phosphorylation at Thr-881, concomitant with an instantaneous increase in proton efflux from roots.  The direct interaction between AHA2 and PSY1R observed might provide a general paradigm for regulation of plasma membrane proton transport by receptor kinases.
PSY1
Here we show that the major plasma membrane proton pumps in Arabidopsis, AHA1 and AHA2, interact directly in vitro and in planta with PSY1R, a receptor kinase of the plasma membrane that serves as a receptor for the peptide growth hormone PSY1.  The intracellular protein kinase domain of PSY1R phosphorylates AHA2/AHA1 at Thr-881, situated in the autoinhibitory region I of the C-terminal domain.  The direct interaction between AHA2 and PSY1R observed might provide a general paradigm for regulation of plasma membrane proton transport by receptor kinases.
PSY1R
Here we show that the major plasma membrane proton pumps in Arabidopsis, AHA1 and AHA2, interact directly in vitro and in planta with PSY1R, a receptor kinase of the plasma membrane that serves as a receptor for the peptide growth hormone PSY1.  The intracellular protein kinase domain of PSY1R phosphorylates AHA2/AHA1 at Thr-881, situated in the autoinhibitory region I of the C-terminal domain.  Application of PSY1 to plant seedlings induced rapid in planta phosphorylation at Thr-881, concomitant with an instantaneous increase in proton efflux from roots.  The direct interaction between AHA2 and PSY1R observed might provide a general paradigm for regulation of plasma membrane proton transport by receptor kinases.
PSY1