title: Structure of transportin SR2, a karyopherin involved in human disease, in complex with Ran.
abstract: Transportin SR2 (TRN-SR2) is a β-type karyopherin responsible for the nuclear import of specific cargoes, including serine/arginine-rich splicing factors. The protein has been implicated in a variety of human diseases, including HIV infection, primary biliary cirrhosis and limb-girdle muscular dystrophy 1F. Towards understanding its molecular mechanism, a 2.9 Å resolution crystal structure of human TRN-SR2 complexed with the small GTPase Ran has been determined. TRN-SR2 is composed of 20 α-helical HEAT repeats forming a solenoid-like fold. The first nine repeats form a `cradle' for the binding of RanGTP, revealing similarities but also differences with respect to the related importin 13 complex.
authors.affiliation: Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Herestraat 49 bus 822, 3000 Leuven, Belgium.
authors.forename: Vicky G
authors.initials: VG
authors.lastname: Tsirkone
authors.affiliation: Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Herestraat 49 bus 822, 3000 Leuven, Belgium.
authors.forename: Katrien G
authors.initials: KG
authors.lastname: Beutels
authors.affiliation: Laboratory of Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Herestraat 49 bus 822, 3000 Leuven, Belgium.
authors.forename: Jonas
authors.initials: J
authors.lastname: Demeulemeester
authors.affiliation: Laboratory of Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Herestraat 49 bus 822, 3000 Leuven, Belgium.
authors.forename: Zeger
authors.initials: Z
authors.lastname: Debyser
authors.affiliation: Laboratory of Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Herestraat 49 bus 822, 3000 Leuven, Belgium.
authors.forename: Frauke
authors.initials: F
authors.lastname: Christ
authors.affiliation: Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Herestraat 49 bus 822, 3000 Leuven, Belgium.
authors.forename: Sergei V
authors.initials: SV
authors.lastname: Strelkov
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D006801:Humans; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D028961:beta Karyopherins / Q000737:chemistry*; D020931:ran GTP-Binding Protein / Q000737:chemistry*
chemical_list: C120587:RAN protein, human; D028961:beta Karyopherins; C424165:transportin SR2; D020931:ran GTP-Binding Protein
keywords: molecular mechanism; nuclear import; transportin SR2