title: Yeast ubiquitin ligase Rsp5 contains nuclear localization and export signals.
abstract: The Rsp5 ubiquitin ligase regulates numerous cellular processes. Rsp5 is mainly localized to the cytoplasm but nuclear localization was also reported. A potential nuclear export signal was tested for activity by using a GFP(2) reporter. The 687-LIGGIAEIDI-696 sequence located in the Hect domain was identified as a nuclear export signal active in a Crm1-dependent manner, and its importance for the localization of Rsp5 was documented by using fluorescence microscopy and a lacZ-based reporter system. Analysis of the cellular location of other Rsp5 fragments fused with GFP(2) indicated two independent potential nuclear localization signals, both located in the Hect domain. We also uncovered Rsp5 fragments that are important to targeting/tethering Rsp5 to various regions in the cytoplasm. The presented data indicate that Rsp5 ligase is a shuttling protein whose distribution within the cytoplasm and partitioning between cytoplasmic and nuclear locations is determined by a balance between the actions of several targeting sequences and domains.
authors.affiliation: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Cholbinski
authors.forename: Zaneta
authors.initials: Z
authors.lastname: Jastrzebska
authors.forename: Monika
authors.initials: M
authors.lastname: Wysocka-Kapcinska
authors.forename: Danuta
authors.initials: D
authors.lastname: Plochocka
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Gornicka
authors.forename: Anita K
authors.initials: AK
authors.lastname: Hopper
authors.forename: Teresa
authors.initials: T
authors.lastname: Zoladek
mesh_terms: D000595:Amino Acid Sequence; D002467:Cell Nucleus / Q000378:metabolism; D056827:Endosomal Sorting Complexes Required for Transport / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D055786:Gene Knockout Techniques; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D028884:Karyopherins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D049790:Nuclear Export Signals / Q000235:genetics*; D019913:Nuclear Localization Signals / Q000235:genetics*; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D043743:Ubiquitin-Protein Ligase Complexes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000097606:Exportin 1 Protein
chemical_list: D056827:Endosomal Sorting Complexes Required for Transport; D049452:Green Fluorescent Proteins; D028884:Karyopherins; D049790:Nuclear Export Signals; D019913:Nuclear Localization Signals; D010446:Peptide Fragments; D018160:Receptors, Cytoplasmic and Nuclear; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D043743:Ubiquitin-Protein Ligase Complexes; D000097606:Exportin 1 Protein; C469287:RSP5 protein, S cerevisiae