title: Characterization of the transport signals that mediate the nucleocytoplasmic traffic of low risk HPV11 E7.
abstract: We previously discovered that nuclear import of low risk HPV11 E7 is mediated by its zinc-binding domain via a pathway that is independent of karyopherins/importins (Piccioli et al., 2010. Virology 407, 100-109). In this study we mapped and characterized a leucine-rich nuclear export signal (NES), 76IRQLQDLLL84, within the zinc-binding domain that mediates the nuclear export of HPV11 E7 in a CRM1-dependent manner. We also identified a mostly hydrophobic patch 65VRLVV69 within the zinc-binding domain that mediates nuclear import of HPV11 E7 via hydrophobic interactions with the FG-repeats domain of Nup62. Substitutions of hydrophobic residues to alanine within the 65VRLVV69 sequence disrupt the nuclear localization of 11E7, whereas the R66A mutation has no effect. Overall the data support a model of nuclear entry of HPV11 E7 protein via hydrophobic interactions with FG nucleoporins at the nuclear pore complex.
authors.affiliation: Biology Department, Boston College, Chestnut Hill, MA 02467, United States.
authors.forename: Courtney H
authors.initials: CH
authors.lastname: McKee
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Onder
authors.forename: Aditya
authors.initials: A
authors.lastname: Ashok
authors.forename: Rebeca
authors.initials: R
authors.lastname: Cardoso
authors.forename: Junona
authors.initials: J
authors.lastname: Moroianu
mesh_terms: D021581:Active Transport, Cell Nucleus; D052140:Human papillomavirus 11 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D028884:Karyopherins / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D028861:Nuclear Pore Complex Proteins / Q000378:metabolism; D050725:Papillomavirus E7 Proteins / Q000235:genetics / Q000378:metabolism*; D021382:Protein Sorting Signals; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D000097606:Exportin 1 Protein
chemical_list: D028884:Karyopherins; D008562:Membrane Glycoproteins; D028861:Nuclear Pore Complex Proteins; D050725:Papillomavirus E7 Proteins; D021382:Protein Sorting Signals; D018160:Receptors, Cytoplasmic and Nuclear; D000097606:Exportin 1 Protein; C049312:nuclear pore protein p62