title: Localization of a bacterial group II intron-encoded protein in eukaryotic nuclear splicing-related cell compartments.
abstract: Some bacterial group II introns are widely used for genetic engineering in bacteria, because they can be reprogrammed to insert into the desired DNA target sites. There is considerable interest in developing this group II intron gene targeting technology for use in eukaryotes, but nuclear genomes present several obstacles to the use of this approach. The nuclear genomes of eukaryotes do not contain group II introns, but these introns are thought to have been the progenitors of nuclear spliceosomal introns. We investigated the expression and subcellular localization of the bacterial RmInt1 group II intron-encoded protein (IEP) in Arabidopsis thaliana protoplasts. Following the expression of translational fusions of the wild-type protein and several mutant variants with EGFP, the full-length IEP was found exclusively in the nucleolus, whereas the maturase domain alone targeted EGFP to nuclear speckles. The distribution of the bacterial RmInt1 IEP in plant cell protoplasts suggests that the compartmentalization of eukaryotic cells into nucleus and cytoplasm does not prevent group II introns from invading the host genome. Furthermore, the trafficking of the IEP between the nucleolus and the speckles upon maturase inactivation is consistent with the hypothesis that the spliceosomal machinery evolved from group II introns.
authors.affiliation: Consejo Superior de Investigaciones Científicas, Estación Experimental del Zaidín Grupo de Ecología Genética, Granada, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Nisa-Martínez
authors.affiliation: Centre National de la Recherche Scientifique, Institut des Sciences du Végétal, Gif-sur-Yvette, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Laporte
authors.affiliation: Consejo Superior de Investigaciones Científicas, Estación Experimental del Zaidín Grupo de Ecología Genética, Granada, Spain.
authors.forename: José Ignacio
authors.initials: JI
authors.lastname: Jiménez-Zurdo
authors.affiliation: Centre National de la Recherche Scientifique, Institut des Sciences du Végétal, Gif-sur-Yvette, France.
authors.forename: Florian
authors.initials: F
authors.lastname: Frugier
authors.affiliation: Centre National de la Recherche Scientifique, Institut des Sciences du Végétal, Gif-sur-Yvette, France.
authors.forename: Martin
authors.initials: M
authors.lastname: Crespi
authors.affiliation: Centre National de la Recherche Scientifique, Institut des Sciences du Végétal, Gif-sur-Yvette, France.
authors.forename: Nicolás
authors.initials: N
authors.lastname: Toro
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000382:microbiology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007438:Introns / Q000235:genetics*; D009154:Mutation / Q000235:genetics; D011523:Protoplasts / Q000378:metabolism / Q000382:microbiology; D012326:RNA Splicing / Q000235:genetics*; D012329:RNA, Bacterial / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016962:Sinorhizobium meliloti / Q000235:genetics* / Q000254:growth & development; D017381:Spliceosomes / Q000235:genetics; D013347:Subcellular Fractions
chemical_list: D001426:Bacterial Proteins; C066496:DegS protein, Bacteria; D012329:RNA, Bacterial; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins