Functional analysis of a putative Ca2+ channel gene TaTPC1 from wheat.

The cytosolic free-calcium concentration [Ca2+](cyt) transiently increases under abiotic stresses and the proteins that control this process are gradually disclosed. The Ca2+-permeable channel is one type of these proteins in plants. In the present study, a novel Ca2+-permeable channel gene TaTPC1 encoding a putative membrane protein was cloned from wheat. It was induced under high salinity, polyethylene glycol, low temperature (4 degrees C), and abscisic acid. Expression of TaTPC1 in the yeast mutant lacking CCH1 can recover its growth under lithium stress through functional complementation. TaTPC1 transgenic plants exhibited more stomatal closing in the presence of Ca2+ than the control, supporting a role for the calcium channel in regulating plant responses to environmental change.