Study On The Expression Of Rice Sucrose Synthase Gene Family By RNAi And Prokaryotic Expression

As the main output of higher plant photosynthesis in higher plant, sucrose is also the main form of carbohydrate transport process, sucrose play an important role in long-distance transport of sugars and plays the role of signaling molecules. Studies suggest that in metabolic pathways associated with sucrose there are three basically types of enzymes, namely Invertase (Inv), sucrose phosphate synthase (SPS) and sucrose synthase (SUS). Sucrose synthase which has the ability of sucrose decomposition and sucrose synthesis, the former is the major role of sucrose synthase that decompose sucrose to provide precursors for cellulose synthesis or starch synthesis. Sucrose synthase also related to the sugar input, cell wall synthesis and storage capacity, these functions are achieved by sucrose synthase regulate the level of sugar decomposition.At present, the studies of sucrose synthase gene family show that there is a certain difference between the members’structure, but they are still similar to each other in high degree. Each family member plays a different role in different stages of plant growth, and ultimately all members of the family get together to complete the synthesis of sucrose metabolism-related functions. Rice sucrose synthase gene family members individual function is not yet clearly, researchers only infer gene function that lack of actual experimental data.In order to the function and interaction of each member of the rice sucrose synthase gene family, firstly, by optimizing the process of genetically modified Agrobacterium transformation method to improve the efficiency of gene transfer in rice, on this basis in accordance with the cDNA sequences of rice sucrose synthase gene family to designed primers, then constructed six RNA interfere expression vectors that SUS1-6RNAi of pGAQ3426h vectors. Through the Agrobacterium-mediated transformation method, the six expression vectors were transformed rice callus, then TO transgenic plants obtained by differentiation of callus. After identified by PCR program we got43positive lines. PCR analysis showed that the gene is stable in genome of T1transgenic plants and gene isolation rate of T1generation is3:1that accorded with genetic law. T1generation plants were randomly sampled for the RT-PCR analysis confirmed that the expression of RNA interference in the T1generation plants and inhibited function of sucrose synthase gene in transcription level, picked lines which was inhibited significantly and selected pure lines for next step of the experiment, in order to research rice sucrose synthase gene family features through the phenotype of pure lines.In this paper, we also determined the conditions for prokaryotic expression through the optimization of rice sucrose synthase gene prokaryotic expression conditions. And Immunofluorescence experiment further research expression patterns of transgenic rice callus. The above experiments has laid a good foundation for the research of rice sucrose synthase.