title: FLP-mediated site-specific recombination for genome modification in turfgrass.
abstract: To develop molecular strategies for gene containment in genetically modified (GM) turfgrass, we have studied the feasibility of using the FLP/FRT site-specific DNA recombination system from yeast for controlled genome modification in turfgrass. Suspension cell cultures of creeping bentgrass (Agrostis stolonifera L.) and Kentucky bluegrass (Poa pratensis) were co-transformed with a FLP recombinase expression vector and a recombination-reporter test plasmid containing beta-glucuronidase (gusA) gene which was separated from the maize ubiquitin (ubi) promoter by an FRT-flanked blocking DNA sequence to prevent its transcription. GUS activity was observed in co-transformed cells, in which molecular analyses indicated that FLP-mediated excision of the blocking sequence had brought into proximity the upstream promoter and the downstream reporter gene, resulting in GUS expression. Functional evaluation of the FLP/FRT system using transgenic creeping bentgrass stably expressing FLP recombinase confirmed the observation in suspension cell culture. Our results indicate that FLP/FRT system is a useful tool for genetic manipulation of turfgrass, pointing to the great potential of exploiting the system to develop molecular strategies for transgene containment in perennials.
authors.affiliation: Department of Genetics, Biochemistry and Life Science Studies, Clemson University, 100 Jordan Hall, Clemson, SC 29634, USA.
authors.forename: Qian
authors.initials: Q
authors.lastname: Hu
authors.forename: Kimberly
authors.initials: K
authors.lastname: Nelson
authors.forename: Hong
authors.initials: H
authors.lastname: Luo
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics; D031703:Agrostis / Q000235:genetics; D001709:Biotechnology / Q000379:methods*; D004247:DNA / Q000235:genetics / Q000378:metabolism; D005821:Genetic Techniques; D018745:Genome, Plant; D005966:Glucuronidase / Q000235:genetics; D008957:Models, Genetic; D030821:Plants, Genetically Modified; D010957:Plasmids / Q000378:metabolism; D006109:Poaceae / Q000235:genetics*; D011995:Recombination, Genetic; D019076:Transgenes
chemical_list: D004247:DNA; D005966:Glucuronidase