Tobacco genetic engineering

The EPA approved the release of the first genetically engineered crop, gene-altered tobacco plants. 

Moffat, A.S. (1991h). Plant pharmers" transform tobacco to prodnce proteins. Genetic Engineering News November/ December, 1 55. 

Nevertheless, genetic engineering of a key enzyme in a chosen pathway does not always result in the enhancement of the end product thus, overexpression of pmt gene carried out in A. belladonna resulted in a 5-fold increased in pmt transcript level but an unchanged tropane alkaloid profile (hyoscyamine and scopolamine), as well as the tropane alkaloids biosynthetic precursors tropine, pseudotropine and tropinone which were not affected [134-135], Similarly, the overexpression of tobacco pmt gene in Dubosia hybrid hairy root cultures produced amounts of tropane alkaloid similar to control roots [131, 136]. All these results seem to indicate the presence of different points of control in the tropane alkaloid metabolic pathway. 

The second case of resistance involves larvae of the tobacco budworm selected with a genetically engineered strain of the epiphytic bacterium Pseudomonas fluorescens... 

Mori, M., et ah, Efficient production of human gamma interferon in tobacco protoplasts by genetically engineered brome mosaic vims RNAs. J Gen Virol, 1993 74 (Pt 7) 1255-1260. 

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