Identification and functional characterization of Ca²⁺-permeable stretch-activated channels from rice and tobacco

Abstract

Though Ca²⁺-permeable stretch-activated channels are postulated to play crucial roles in various signal transduction pathways in plants, their molecular identity is totally unknown. We here identified genes from rice (OsMID1) and tobacco (NtMID1A/B) that functionally complemented a yeast mutant defective in the MID1 gene encoding a putative Ca²⁺-permeable SA channel component. To investigate functions of these genes, we developed transgenic plants as well as suspension-cultured cells in which their expression are enhanced or repressed. Possible interaction of the plant MID1 family with other types of Ca²⁺ channels will also be discussed.