Activation of a plant plasma membrane Ca2+ channel by TGalpha1, a heterotrimeric G protein alpha-subunit homologue

Abstract

Wild-type and GTPase-deficient recombinant TGalpha1 were used along patch-clamp techniques to study the role of heterotrimeric G proteins in the regulation of the hyperpolarized active tomato plasma membrane Ca2+ channel. Recombinant alpha-subunits induced an increase in channel activity as shown by the increase in channel events and the mean open probability of the channel. Our results suggest a membrane-delimited pathway involving heterotrimeric G proteins in Ca2+ channel activation.