Abstract
Rice heterotrimeric G Protein α, β and γ subunits were localized on plasma membrane fraction. Gel filtration of solubilized plasma membrane proteins showed that all subunits were present in the large protein complexes (about 400kDa). Interestingly, β and γ subunits are present in the 60kDa fraction. As β and γ subunit form a dimmer in mammals and yeast, the 60kDa fraction may be the βγ dimmer in rice. In order to presume the function of the β subunit, we produced the transformants suppressed the expression of β subunit gene by using RNAi methods. First, transformants which the amount of the β subunit was decreased were selected. All transformants showed the abnormal phenotypes, dwarf, lethality and small seeds. These phenotypes were not same as that of the α subunit deficient mutant. These results indicate that the β subunit may be partially separated from the α subunit.
