title: Nuclear localization signal-dependent and -independent movements of Drosophila melanogaster dUTPase isoforms during nuclear cleavage.
abstract: Two dUTPase isoforms (23 kDa and 21 kDa) are present in the fruitfly with the sole difference of an N-terminal extension. In Drosophila embryo, both isoforms are detected inside the nucleus. Here, we investigated the function of the N-terminal segment using eYFP-dUTPase constructs. In Schneider 2 cells, only the 23 kDa construct showed nuclear localization arguing that it may contain a nuclear localization signal (NLS). Sequence comparisons identified a lysine-rich nonapeptide with similarity to the human c-myc NLS. In Drosophila embryos during nuclear cleavages, the 23 kDa isoform showed the expected localization shifts. Contrariwise, although the 21 kDa isoform was excluded from the nuclei during interphase, it was shifted to the nucleus during prophase and forthcoming mitotic steps. The observed dynamic localization character showed strict timing to the nuclear cleavage phases and explained how both isoforms can be present within the nuclear microenvironment, although at different stages of cell cycle.
authors.affiliation: Institute of Enzymology, Hungarian Academy of Sciences, Laboratory of Genome Metabolism and Repair, Karolina út 29, H-1113, P.O. Box 7, H-1518 Budapest, Hungary.
authors.forename: Villo
authors.initials: V
authors.lastname: Muha
authors.forename: Imre
authors.initials: I
authors.lastname: Zagyva
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Venkei
authors.forename: János
authors.initials: J
authors.lastname: Szabad
authors.forename: Beáta G
authors.initials: BG
authors.lastname: Vértessy
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002453:Cell Cycle; D002467:Cell Nucleus / Q000201:enzymology*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000201:enzymology; D004625:Embryo, Nonmammalian / Q000201:enzymology; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D019913:Nuclear Localization Signals / Q000378:metabolism*; D011755:Pyrophosphatases / Q000235:genetics / Q000378:metabolism*
chemical_list: D007527:Isoenzymes; D019913:Nuclear Localization Signals; D011755:Pyrophosphatases; C023278:uridine triphosphatase