title: Intrachromosomal recombination between attP regions as a tool to remove selectable marker genes from tobacco transgenes.
abstract: Recombinant genes conferring resistance to antibiotics or herbicides are widely used as selectable markers in plant transformation. Once transgenic material has been selected, the marker gene is dispensable. We report a novel strategy to remove undesirable parts of a transgene after integration into the tobacco genome. This approach is based on the transfer of a vector containing a NPTII gene flanked by two 352 bp attachment P (attP) regions of bacteriophage lambda, and the identification of somatic tissue with deletion events following intrachromosomal recombination between the attP regions. This system was used to delete a 5.9 kb region from a recombinant vector that had been inserted into two different genomic regions. As the attP system does not require the expression of helper proteins to induce deletion events, or a genetic segregation step to remove recombinase genes, it should provide a useful tool to remove undesirable transgene regions, especially in vegetatively propagated species.
authors.affiliation: Leeds Institute for Plant Biotechnology and Agriculture (LIBA), Faculty of Biological Sciences, The University of Leeds, Leeds LS2 9JT, United Kingdom.
authors.forename: E
authors.initials: E
authors.lastname: Zubko
authors.forename: C
authors.initials: C
authors.lastname: Scutt
authors.forename: P
authors.initials: P
authors.lastname: Meyer
mesh_terms: D010582:Bacteriophage lambda / Q000235:genetics; D001483:Base Sequence; D015139:Blotting, Southern; D002875:Chromosomes / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D005818:Genetic Engineering / Q000379:methods; D005819:Genetic Markers; D005822:Genetic Vectors; D007613:Kanamycin Resistance / Q000235:genetics*; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000502:physiology; D010947:Plants, Toxic; D016133:Polymerase Chain Reaction / Q000379:methods; D011995:Recombination, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D017384:Sequence Deletion; D014026:Nicotiana / Q000235:genetics* / Q000502:physiology
chemical_list: D004269:DNA, Bacterial; D018744:DNA, Plant; D005819:Genetic Markers; C036483:T-DNA