Research Of Regulatory Sequence Of PST2a Gene Of Sugarcane

Promoter is an important element in expression regulation. It highly effect the expression level of transgenic plant. So choose a high expression promoter is the key to make sure the foreign gene highly express in the transgenic plant. Constitutive promoters have been used extremely as useful tools in many plant transgenic researches. Because of lacking temporal and spatial regulation, constitutive promoters have a number of potential drawbacks in genetic improved crops. Tissue-specific promoter, a class of the most useful promoters, can drive genes expression in temporal and spatial patterns. They not only can increase transgene expression in specific organs or developmental stages, but also can avoid unnecessary energy waste. So find an high expression or tissue-specific promoters is important to transgene of sugarcane.1968bp of 5'regulatory sequence of PST2a gene was cloned and named pPST2a by our lab. To further identify it's expression characteristic, a list of plant deletion expression vectors was constructed:pCBI1900,pCBI1600,pCBI1300,pCBI1100; These deletion expression vectors were transferred into Agrobacterium tumerfaciens EHA105 by using "Freezing and thawing" method and transformed into sugarcane and obtained a lot of transformed plant. These transformed plants were confirmed by using the method of PCR. The result confirmed that there were 16,33,29 and 21 transgenic plant of pCBI1900,pCBI1600,pCBI1300 and pCBI1100. Choose some transgenic plants of each deletion vector for GUS histochemistry staining. Results show that GUS gene only express in root of transgenic plant of pCBI1900,pCBI1600,pCBI1300,but not in other tissue of transgenic plant. GUS gene was not express in any tissue of transgenic plant of pCBI1100 including root. Thus prove that pCBI1900,pCBI1600,pCBI1300 have root specific express characteristic. Also prove that regulatory sequence pPST2a have root specific express characteristic. To further indentify this regulatory sequence's express characteristic in other plant, we also do the transformation to the tobacco. Confirmed by PCR of GUS gene, we obtained 27 and 33 of transgenic tobaccos of pCBI1900 and pCBI1600. Further research of these transgenic tobaccos are under way.