Abstract
There are several types of K+ channel in organisms and they play various roles in cells. In order to investigate physiological meanings of K+ channel in rice, we studied expression and localization of putative outwardly rectifying K+ channel gene (ROK) cloned from 3 varieties of rice, Hitomebore, Hidekomochi and Nipponbare, Japonica cultivar. Phylogenetic analysis of plant K+ channels supported ROK in the outwardly rectifying groups. Specific expression of ROK in anthers revealed higher in the stage at 10 days than 5 days before the heading.
Microsomal membranes of ROK expressing yeast cells were fractionated through sucrose gradient and studied with using antibodies raised against organella marker proteins (PM Pma1, VM Vam3, ER Kar2, Golgi IDPase). Distribution pattern of the ROK protein showed mainly in the ER neither in tonoplast nor plasmamembrane, which was supported by the fusion protein of ROK-GFP expression in suspension-cultured cells of Arabidopsis thaliana.
