Author
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Dong, Niu |
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MONTANEZ, BELEN - MENDEL BIOTECHNOLOGY |
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CREELMAN, ROBERT - MENDEL BIOTECHNOLOGY |
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CORNISH, KATRINA - YULEX CORPORATION |
Submitted to: Plant Cell Reports
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/30/2005 Publication Date: 8/1/2005 Citation: Dong, N., Montanez, B., Creelman, R., Cornish, K. 2005. Low light and low ammonium are key factors for guayule leaf tissue shoot organogenesis and transformation. Plant Cell Reports. 25(1):26-24 Interpretive Summary: It is easy for some plant species to regenerate shoots from their leaf tissues. However, it is very difficult for guayule to do so. We have developed a new method using leaf tissue for guayule regeneration. The key factors for success are low light intensity and low ammonium concentration. The new method can also be used for Agrobacterium-mediated transformation. A 35S promoter driven BAR gene and an ubiquitin-3 promoter driven GUS gene (with intron) have been successfully introduced into guayule. These transgenic guayule plants were resistant to the herbicide ammonium-glufosinate and were positive to GUS staining. Molecular analysis showed the expected band and signal in all GUS positive transformants. Technical Abstract: A new method has been developed for guayule tissue culture and transformation. Guayule leaf explants have a poor survival rate when placed on normal MS medium and under normal culture room light conditions. Low light and low ammonium treatment greatly improved shoot organogenesis and transformation from leaf tissues. Using this method, a 35S promoter driven BAR gene and an ubiquitin-3 promoter driven GUS gene (with intron) have been successfully introduced into guayule. These transgenic guayule plants were resistant to the herbicide ammonium-glufosinate and were positive to GUS staining. Molecular analysis showed the expected band and signal in all GUS positive transformants. Transformation with a pBIN19 based plasmid containing a NPTII gene and then selection with kanamycin also works well using this method. The ratio of kanamycin resistant calli to total start explants reached 50% in some experiments. |