Transgenic tobacco simultaneously overexpressing glyphosate N-acetyltransferase and 5-enolpyruvylshikimate-3-phosphate synthase are more resistant to glyphosate than those containing one gene

• Published in: Transgenic research 2015-08, Vol.24 (4), p.753-763
• Main Authors: Liu, Yunjun, Cao, Gaoyi, Chen, Rongrong, Zhang, Shengxue, Ren, Yuan, Lu, Wei, Wang, Jianhua, Wang, Guoying
• Format: Article
• Language: English
• Subjects: 3-Phosphoshikimate 1-Carboxyvinyltransferase - genetics; 3-Phosphoshikimate 1-Carboxyvinyltransferase - metabolism; Acetyltransferases - genetics; Acetyltransferases - metabolism; Animal Genetics and Genomics; Biomedical and Life Sciences; Biomedical Engineering/Biotechnology; Drug Resistance - genetics; Genetic Engineering; Glycine - analogs & derivatives; Glycine - pharmacology; Glyphosate; Herbicides - pharmacology; Life Sciences; Molecular Medicine; Nicotiana - drug effects; Nicotiana - enzymology; Nicotiana - genetics; Original Paper; Plant Genetics and Genomics; Plant Leaves - drug effects; Plant Leaves - enzymology; Plants, Genetically Modified - drug effects; Plants, Genetically Modified - enzymology; Plants, Genetically Modified - genetics; Polymerase Chain Reaction - methods; Transgenics
• ISSN: 0962-8819; 1573-9368
• DOI: 10.1007/s11248-015-9874-8

5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS) and glyphosate N-acetyltransferase (GAT) can detoxify glyphosate by alleviating the suppression of shikimate pathway. In this study, we obtained transgenic tobacco plants overexpressing AM79 aroA, GAT, and both of them, respectively, to evaluate whether overexpression of both genes could confer transgenic plants with higher glyphosate resistance. The transgenic plants harboring GAT or AM79 aroA, respectively, showed good glyphosate resistance. As expected, the hybrid plants containing both GAT and AM79 aroA exhibited improved glyphosate resistance than the transgenic plants overexpressing only a single gene. When grown on media with high concentration of glyphosate, seedlings containing a single gene were severely inhibited, whereas plants expressing both genes were affected less. When transgenic plants grown in the greenhouse were sprayed with glyphosate, less damage was observed for the plants containing both genes. Metabolomics analysis showed that transgenic plants containing two genes could maintain the metabolism balance better than those containing one gene after glyphosate treatment. Glyphosate treatment did not lead to a huge increase of shikimate contents of tobacco leaves in transgenic plants overexpressing two genes, whereas significant increase of shikimate contents in transgenic plants containing only a single gene was observed. These results demonstrated that pyramiding both aroA and GAT in transgenic plants can enhance glyphosate resistance, and this strategy can be used for the development of transgenic glyphosate-resistant crops.