title: An improved chemically inducible gene switch that functions in the monocotyledonous plant sugar cane.
abstract: Chemically inducible gene switches can provide precise control over gene expression, enabling more specific analyses of gene function and expanding the plant biotechnology toolkit beyond traditional constitutive expression systems. The alc gene expression system is one of the most promising chemically inducible gene switches in plants because of its potential in both fundamental research and commercial biotechnology applications. However, there are no published reports demonstrating that this versatile gene switch is functional in transgenic monocotyledonous plants, which include some of the most important agricultural crops. We found that the original alc gene switch was ineffective in the monocotyledonous plant sugar cane, and describe a modified alc system that is functional in this globally significant crop. A promoter consisting of tandem copies of the ethanol receptor inverted repeat binding site, in combination with a minimal promoter sequence, was sufficient to give enhanced sensitivity and significantly higher levels of ethanol inducible gene expression. A longer CaMV 35S minimal promoter than was used in the original alc gene switch also substantially improved ethanol inducibility. Treating the roots with ethanol effectively induced the modified alc system in sugar cane leaves and stem, while an aerial spray was relatively ineffective. The extension of this chemically inducible gene expression system to sugar cane opens the door to new opportunities for basic research and crop biotechnology.
authors.affiliation: Syngenta Centre for Sugar Cane Biofuels Development, Centre for Tropical Crops and Biocommodities, Queensland University of Technology, Brisbane, QLD, 4001, Australia, Mark.Kinkema@qut.edu.au.
authors.forename: Mark
authors.initials: M
authors.lastname: Kinkema
authors.forename: R Jason
authors.initials: RJ
authors.lastname: Geijskes
authors.forename: Kylie
authors.initials: K
authors.lastname: Shand
authors.forename: Heather D
authors.initials: HD
authors.lastname: Coleman
authors.forename: Paulo C
authors.initials: PC
authors.lastname: De Lucca
authors.forename: Anthony
authors.initials: A
authors.lastname: Palupe
authors.forename: Mark D
authors.initials: MD
authors.lastname: Harrison
authors.forename: Ian
authors.initials: I
authors.lastname: Jepson
authors.forename: James L
authors.initials: JL
authors.lastname: Dale
authors.forename: Manuel B
authors.initials: MB
authors.lastname: Sainz
mesh_terms: D000426:Alcohol Dehydrogenase / Q000235:genetics; D001233:Aspergillus nidulans / Q000235:genetics; D017796:Caulimovirus / Q000235:genetics; D018556:Crops, Agricultural / Q000235:genetics; D000431:Ethanol / Q000494:pharmacology*; D005656:Fungal Proteins / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D017343:Genes, Plant / Q000235:genetics*; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D006651:Histocytochemistry; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D031786:Saccharum / Q000235:genetics* / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D011993:Recombinant Fusion Proteins; D000431:Ethanol; D000426:Alcohol Dehydrogenase; D005966:Glucuronidase