[Objective] This study aimed to conduct prokaryotic expression of rice SDG711 C-terminal and to prepare its polyclonal antibody. [Method] C-terminal of rice SDG711 containing relatively intensive antigen determinants was selected for prokaryotic expression, prokaryotic expression vector pET28a-711C was constructed and the recombinant plasmid was transformed into Escherichia coli BL21 （DE3） competent cells. The recombinant fusion protein was induced by IPTG and purified to immunize a New Zealand white rabbit as the antigen, and polyclonal antibody was obtained and confirmed by Western-blot analysis. [Result] The polyclonal anti- body was successfully prepared and could efficiently detect the expressed antigen. [Conclusion] This study laid the foundation for further investigating the functions of SDG711 protein in rice.
Based on the evidence that Al resistance is an inducible process and rice is an Al-resistant crop, identification of Al-responsive genes from rice may help to further clone Al.resistant genes in plants. Semi-quantitative and real-time polymerase chain reaction （PCR） is widely applied in gene transcrip- tional analyses, particularly for those genes with low transcript abundance. Normalization with proper endogenous control （EC） genes is critical for these two approaches in terms of reliability and precision. We first noticed that the expression of several commonly-used EC genes was depressed under AI stress, while sulfite reductase gene （SR） was stable throughout the AI treatment. The reliability of SR as an EC gene was further tested by analyzing the expression of a number of genes in response to Al challenge. Except for the consistent results obtained for the four previously-identified genes, nine additional genes were newly defined as Al-responsive in this study. Collectively, our results suggest that SR can be used as a novel EC gene for semi-quantitative and real-time PCR analysis of Al responsive genes, and that activated transport of silicon and stimulated metabolism of carotenoid and terpenoid could be involved in Al resistance in rice plants.
