Reverse Genetic Analysis of Transcription Factor Os Hox9, a Member of Homeobox Family, in Rice

Homeobox transcription factors participate in the growth and development of plants by regulating cell differentiation, morphogenesis and environmental signal response. To reveal the functions of these transcription factors in rice, we constructed the RNAi vectors of OsHox9, a member of homeobox family, and analyzed the function of OsHox9 using reverse genetics. The plant height and tillering number of RNAi transgenic plants decreased compared with those of wild-type plants. Reverse transcdption-polymerase chain reaction analysis showed that OsHox9 expression reduced in the transgenic plants with phenotypic variance, whereas that in the transgenic plants without phenotypic variance was similar to that in the wild-type plants. This result suggests that the phenotypes of the transgenic plants were caused by RNAi effects. The tissue-specificity of OsHox9 expression indicated that it was expressed in different organs, with high expression in stem apical medstem and young panicles. Subcellular location of OsHox9 demonstrated that it was localized on the cell membrane.