[Construction of RNAi binary vector of soybean receptor-like kinase gene (rlpk2) and its soybean transformation].

Plant receptor-like kinases (RLKs) play important roles in plant growth, development and responses to environmental stress. RNA interference (RNAi) is a powerful tool to study functions of RLKs. In this study, a 312bp 3'end cDNA fragment of the soybean receptor-like kinase gene rlpk2 was chosen to construct the rlpk2-RNAi expression cassette. The binary vector pART27-R2 harboring rlpk2-RNAi expression cassette was constructed through three times subcloning via mid-clone vector and then transformed into Agrobacterium LBA4404. Three independent transgenic plants were obtained by Agrobactium-mediated soybean cotyledon transformation method. RT-PCR analysis showed that rlpk2 gene was successfully knocked down in all transgenic plants. It was found that photosynthesis activities of rlpk2-RNAi transgenic leaves were much improved, suggesting rlpk2 may function as a negative regulator of soybean leaf functions and/or chloroplast structure.