Functional Analysis Of OsPht1;3and OsPht1;5in Oryza Sativa

Plant phosphate (Pi) transporters (PTs) comprise a large family with important roles in Pi uptake, translocation and redistribution for plant growth and development. In rice (Oryza sativa)13PTs belonging to PHT subfamily (designated as PHT1-13) were identified. Among them some PTs functions have been reported, such as PT1, PT2, PT6, PT8, PT9, PT10and PT11, while the functions of others have not been described. In this study, we cloned PT3and PTS and developed the transgenic lines with overexpressions of them to in order to evaluate their functions. The results from the present study are summarized as follows:1. The To generation of transgenic plants were confirmed by Hygromycin PCR and Southern blotting analysis. We selected two independent single copy transformed PT3or PT5transgenic lines (PT3(0)1, PT3(O)3, PT5(O)1and PT5(O)3), respectively, for the genes expressions analysis using quantitative real time PCR (qRT-PCR). The result of qRT-PCR showed that the genes in the four lines were all overexpressed.2. Under HP hydroponic culture, the30-day-old transgenic plants exhibited significantly reduced biomass of shoots and roots compared to the wild type plants (Nipponbare cv. japonica) with necrosis symptoms in older leaf tips.3. The Pi concentration in shoots and roots of PT3transgenic plants is significantly higher than that of the wild type plants under both HP and LP hydropnic cultures, so does the PT5transgenic plants under HP hydropnic culture. But there is no difference in Pi concentration under LP hydropnic culture.4. We used the ICP-OES to measure the total P and some other elements of the plants, and founded that the PT3transgenic plants under both HP and LP hydropnic cultures, and the PT5transgenic plants under HP hydropnic culture have significantly higher total P in the shoots and roots than that of the wild type plants; But this dose not happen under LP condition.