title: Cytokinin vectors mediate marker-free and backbone-free plant transformation.
abstract: Conventional Agrobacterium-mediated transformation methods rely on complex and genotype-specific tissue culture media for selection, proliferation, and regeneration of genetically modified cells. Resulting transgenic plants may not only contain selectable marker genes but also carry fragments of the vector backbone. Here, we describe a new method for the production of transgenic plants that lack such foreign DNA. This method employs vectors containing the bacterial isopentenyltransferase (ipt) gene as backbone integration marker. Agrobacterium strains carrying the resulting ipt gene-containing "cytokinin" vectors were used to infect explants of various Solanaceous plant species as well as canola (Brassica napus). Upon transfer to hormone-free media, 1.8% to 9.9% of the infected explants produced shoots that contained a marker-free T-DNA while lacking the backbone integration marker. These frequencies often equal or exceed those for backbone-free conventional transformation.
authors.affiliation: J. R. Simplot Company, Simplot Plant Sciences, Boise, ID, 83706, USA.
authors.forename: Craig M
authors.initials: CM
authors.lastname: Richael
authors.forename: Marina
authors.initials: M
authors.lastname: Kalyaeva
authors.forename: Robert C
authors.initials: RC
authors.lastname: Chretien
authors.forename: Hua
authors.initials: H
authors.lastname: Yan
authors.forename: Sathya
authors.initials: S
authors.lastname: Adimulam
authors.forename: Artesia
authors.initials: A
authors.lastname: Stivison
authors.forename: J Troy
authors.initials: JT
authors.lastname: Weeks
authors.forename: Caius M
authors.initials: CM
authors.lastname: Rommens
mesh_terms: D001483:Base Sequence; D017931:DNA Primers; D005822:Genetic Vectors; D030821:Plants, Genetically Modified / Q000235:genetics*; D012231:Rhizobium / Q000235:genetics*; D019657:Solanaceae / Q000235:genetics*; D014170:Transformation, Genetic
chemical_list: D017931:DNA Primers