The expression of tga1a gene from tobacco affects the expression of exogenous gene in transgenic plant
- 13 Downloads
The DNA-binding protein TGA1a of tobacco can specially interact with the enhancer sequence as-1 (-83 to-63) of CaMV35S promoter and show the function of transcriptional activation. In order to study the expression of exogenous gene affected by TGA1a, a trans-acting regulation system was formed by tandem connecting tga1a under the control of the phloem-specific promoter rolC with reporter gene under the control of CaMV35S. Then, the system above was utilized to construct a plant expression vector. Moreover, two plant expression vectors were constructed with the report gene controlled by CaMV35S and rolC promoter respectively as positive controls. Tobacco leaf disc transformed by Agrobacterium-mediated method and transgenic plants were regenerated. It was proved that the reporter gene existed in the genome of transgenic plants by Southern hybridization. The results of GUS activity indicated that the expression of tga1a controlled by rolC remarkably increased the expression of the reporter gene controlled by CaMV35S. GUS activity of transgenic plants containing trans-acting regulation system was higher than that of transgenic plants containing the reporter gene under the control of CaMV35S and rolC respectively, with the highest GUS activity of about tenfolds of two positive controls. Histochemical method demonstrated that GUS staining amassed mainly in phloem tissue of transgenic plants containing the trans-acting regulation system. A new model for arising the expression level and tissue-specific expression of exogenous gene in transgenic plant was established in this study.
Keywordsgene expression and regulation DNA-binding protein TGA1a plant transformation reporter gene
Unable to display preview. Download preview PDF.
- 6.Li Xugang, Lu Zixian, Feng Dejiang et al., The construction of a novel binary plant expression vector and its application, Progess in Natural Science (in Chinese), 2001, 11(4): 368–373.Google Scholar
- 7.Gao Yuefeng, Zhu Zhen, Xiao Guifang et al., Isolation of soybean kuntiz trypsin inhibitor gene and its application in plant insect-resistant genetic engineering, Acta Botanica Sinica (in Chinese), 1998, 40(5): 405–441.Google Scholar
- 9.Sambrook, J., Russell, D. W., Molecular Cloning: A Laboratory Manual, 3rd ed., New York: Cold Spring Harbor Laboratory Press, 2001.Google Scholar
- 13.Li Zhengli, ed., Techniques in Paraffin Section Cutting (in Chinese), Beijing: Science Press, 1987.Google Scholar
- 14.Li Xugang, Lu Zixian, Chen Lei et al., The influence of MARs on transgene expression in transgenic tobaccos, Acta Botanica Sinica (in Chinese), 2001, 43(4): 405–408.Google Scholar