title: Transport of DNA into the nuclei of xenopus oocytes by a modified VirE2 protein of Agrobacterium.
abstract: We used Agrobacterium T-DNA nuclear transport to examine the specificity of nuclear targeting between plants and animals and the nuclear import of DNA by a specialized transport protein. Two karyophilic Agrobacterium virulence (Vir) proteins, VirD2 and VirE2, which presumably associate with the transported T-DNA and function in many plant species, were microinjected into Drosophila embryos and Xenopus oocytes. In both animal systems, VirD2 localized to the cell nuclei and VirE2 remained exclusively cytoplasmic, suggesting that VirE2 nuclear localization signals may be plant specific. Repositioning one amino acid residue within VirE2 nuclear localization signals enabled them to function in animal cells. The modified VirE2 protein bound DNA and actively transported it into the nuclei of Xenopus oocytes. These observations suggest a functional difference in nuclear import between animals and plants and show that DNA can be transported into the cell nucleus via a protein-specific pathway.
authors.affiliation: Department of Biochemistry and Cell Biology, State University of New York, Stony Brook 11794-5215, USA.
authors.forename: B
authors.initials: B
authors.lastname: Guralnick
authors.forename: G
authors.initials: G
authors.lastname: Thomsen
authors.forename: V
authors.initials: V
authors.lastname: Citovsky
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004269:DNA, Bacterial / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000378:metabolism*; D004330:Drosophila / Q000196:embryology; D004625:Embryo, Nonmammalian / Q000502:physiology; D005260:Female; D005822:Genetic Vectors; D007473:Ion Channels; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009865:Oocytes / Q000502:physiology*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D012231:Rhizobium; D017386:Sequence Homology, Amino Acid; D014981:Xenopus
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D007473:Ion Channels; D011994:Recombinant Proteins; C036483:T-DNA; C051583:virE2 protein, Agrobacterium