title: Nuclear importation of Mariner transposases among eukaryotes: motif requirements and homo-protein interactions.
abstract: Mariner-like elements (MLEs) are widespread transposable elements in animal genomes. They have been divided into at least five sub-families with differing host ranges. We investigated whether the ability of transposases encoded by Mos1, Himar1 and Mcmar1 to be actively imported into nuclei varies between host belonging to different eukaryotic taxa. Our findings demonstrate that nuclear importation could restrict the host range of some MLEs in certain eukaryotic lineages, depending on their expression level. We then focused on the nuclear localization signal (NLS) in these proteins, and showed that the first 175 N-terminal residues in the three transposases were required for nuclear importation. We found that two components are involved in the nuclear importation of the Mos1 transposase: an SV40 NLS-like motif (position: aa 168 to 174), and a dimerization sub-domain located within the first 80 residues. Sequence analyses revealed that the dimerization moiety is conserved among MLE transposases, but the Himar1 and Mcmar1 transposases do not contain any conserved NLS motif. This suggests that other NLS-like motifs must intervene in these proteins. Finally, we showed that the over-expression of the Mos1 transposase prevents its nuclear importation in HeLa cells, due to the assembly of transposase aggregates in the cytoplasm.
authors.affiliation: GICC, UMR CNRS 6239, UFR des Sciences et Techniques, Tours, France.
authors.forename: Marie-Véronique
authors.initials: MV
authors.lastname: Demattei
authors.forename: Sabah
authors.initials: S
authors.lastname: Hedhili
authors.forename: Ludivine
authors.initials: L
authors.lastname: Sinzelle
authors.forename: Christophe
authors.initials: C
authors.lastname: Bressac
authors.forename: Sophie
authors.initials: S
authors.lastname: Casteret
authors.forename: Nathalie
authors.initials: N
authors.lastname: Moiré
authors.forename: Jeanne
authors.initials: J
authors.lastname: Cambefort
authors.forename: Xavier
authors.initials: X
authors.lastname: Thomas
authors.forename: Nicolas
authors.initials: N
authors.lastname: Pollet
authors.forename: Pascal
authors.initials: P
authors.lastname: Gantet
authors.forename: Yves
authors.initials: Y
authors.lastname: Bigot
mesh_terms: D021581:Active Transport, Cell Nucleus; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology*; D019295:Computational Biology; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D004330:Drosophila; D005057:Eukaryotic Cells / Q000201:enzymology*; D005453:Fluorescence; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D008970:Molecular Weight; D019913:Nuclear Localization Signals / Q000737:chemistry / Q000378:metabolism; D059828:Plant Cells / Q000378:metabolism; D017354:Point Mutation / Q000235:genetics; D011485:Protein Binding; D055503:Protein Multimerization; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013347:Subcellular Fractions / Q000201:enzymology; D019895:Transposases / Q000737:chemistry* / Q000378:metabolism*; D014981:Xenopus
chemical_list: D004268:DNA-Binding Proteins; D019913:Nuclear Localization Signals; D011993:Recombinant Fusion Proteins; C111652:mariner transposases; D049452:Green Fluorescent Proteins; D019895:Transposases