title: Characterization of the nuclear localization signal of the hepatitis delta virus antigen.
abstract: The delta antigen (HDAg) is the only protein encoded by the hepatitis delta virus (HDV) RNA genome. The HDAg contains an RNA binding domain, a dimerization domain, and a nuclear localization signal (NLS). The nuclear import of HDV RNPs is thought to be one of the first tasks of the HDAg during the HDV replication cycle. Using c-myc-PK fusions with several regions of the HDAg in transfection assays in Huh7 cells, we found that the HDAg NLS consists of a single stretch of 10 amino acids, EGAPPAKRAR, located in positions 66-75. Deletion and mutation analysis of this region showed that both the acidic glutamic acid residue at position 66 and the basic arginine residue at position 75 are essential for promoting nuclear import.
authors: Unidade de Biologia Molecular, Centro de Malária e Outras Doenças Tropicais, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Junqueira, 96 1349-008 Lisboa, Portugal.
authors: Carolina
authors: C
authors: Alves
authors: Natália
authors: N
authors: Freitas
authors: Celso
authors: C
authors: Cunha
mesh_terms: D000595:Amino Acid Sequence; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D017353:Gene Deletion; D017930:Genes, Reporter; D003698:Hepatitis Delta Virus / Q000235:genetics / Q000378:metabolism; D035923:Hepatitis delta Antigens / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D019913:Nuclear Localization Signals / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism; D011770:Pyruvate Kinase / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014162:Transfection
chemical_list: D035923:Hepatitis delta Antigens; D019913:Nuclear Localization Signals; D016271:Proto-Oncogene Proteins c-myc; D011993:Recombinant Fusion Proteins; D011770:Pyruvate Kinase