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This study poplar the presence 飞絮 shedding problems, has obtained tomentosa (Populus tomentosa Carr) PtSEP3-1 on the basis of PtAP1-2 and PtMCP promoter, and further amplified from tomentosa genomic DNA can be obtained PtSEP2 gene 5 'flanking a sequence, expression characteristics through in tobacco and Populus conversion research 4 promoter organization directed regulation for genetic engineering of Populus tomentosa trait of shedding 飞絮 laid the basis for the work. The main findings are as follows: a study using PCR amplified from the genomic DNA in Populus tomentosa floral organ development SEPALLATA2 similar genetic PtSEP2 5 flanking a sequence of approximately 2.3kb, PlantCARE sequence analysis showed that the sequence containing the promoter conserved sequence and a variety of light-responsive element initially speculated for PtSEP2 gene promoter. Further to the GUS reporter gene constructed pPtSEP2 promoter :: GUS plant expression vector, named for PtSEP2 :: GUS. Tobacco roots, stems, leaves, flower buds receptor, transformed by Agrobacterium-mediated transient expression of these four promoter, GUS staining showed that: PtSEP2 promoter GUS activity exists only in the anthers; PtAP1 2 promoter GUS activity in the calyx and petals weakly expressed in roots, stems and leaves were not detected; PtSEP3-1 promoter in tobacco roots, stems, leaves and flowers of the organizations are not detected GUS activity; PtMCP promoter in tobacco roots, stems, leaves and flower buds of the organizations have expressed GUS activity, but the expression was significantly weaker than the 35S promoter, presumed to belong to the moderate constitutive promoter type. The expression vector in clones of Populus in TC1521 and tobacco. Genetic transformation, validation by PCR, Chinese white poplar positive transformed plants were obtained 37, 88 tobacco positive transformed plants. Roots, stems and leaves of transgenic tobacco stained staining of GUS staining results with transient expression results. Transgenic Populus tomentosa seedlings were stained, the results show that the PtSEP2 PtSEP3-1 and PtAP1 of-2 promoter was not detected in the whole plant seedlings, GUS activity. Four pairs to turn PtMCP promoter tobacco roots, stems, leaves and flowers of the organizations GUS activity was measured, the results show that with pBI121 to the promoter PtMCP GUS activity was significantly lower in transgenic tobacco roots, stems, leaves and the GUS activity spend the organizations to turn PtMCP promoter pBI121 GUS activity of 21.9%, 5.3%, 5.3% and 17.6%, respectively. GUS activity is not detected in various tissues of wild-type tobacco. Through the research and analysis concluded: PtSEP2 promoter can drive the GUS gene expressed only in anthers initially speculated that it belongs to anther-specific promoter; PtAP1-2 promoter GUS activity only weakly expressed in the calyx and petals, inferred its possible to spend tissue-specific promoter; roots, stems and leaves were not detected; the PtMCP promoter can drive GUS gene expression in tobacco roots, stems, leaves and flower tissue can, but the expression intensity was weaker than the 35S promoter, are mild constitutive promoter type. In this study, not only for the poplar flowering molecular regulation mechanism has important theoretical significance, but also has potential applications through genetic engineering to improve the poplar 飞絮 shedding problem.
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