Crystal structure of human Karyopherin β2 bound to the PY-NLS of Saccharomyces cerevisiae Nab2

• Published in: Journal of structural and functional genomics Vol. 14; no. 2; pp. 31 - 35
• Main Authors: Soniat, Michael, Sampathkumar, Parthasarathy, Collett, Garen, Gizzi, Anthony S., Banu, Radhika N., Bhosle, Rahul C., Chamala, Swetha, Chowdhury, Sukanya, Fiser, Andras, Glenn, Alan S., Hammonds, James, Hillerich, Brandan, Khafizov, Kamil, Love, James D., Matikainen, Bridget, Seidel, Ronald D., Toro, Rafael, Rajesh Kumar, P., Bonanno, Jeffery B., Chook, Yuh Min, Almo, Steven C.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2013
• Subjects: Amino Acid Sequence; beta Karyopherins - chemistry; beta Karyopherins - metabolism; Binding Sites; Biochemistry; Bioinformatics; Biomedical and Life Sciences; Cell Nucleus - metabolism; Crystallography, X-Ray; Forestry Management; Human Genetics; Humans; Hydrophobic and Hydrophilic Interactions; Life Sciences; Microbial Genetics and Genomics; Molecular Sequence Data; Nuclear Localization Signals - chemistry; Nuclear Localization Signals - metabolism; Nucleocytoplasmic Transport Proteins - chemistry; Nucleocytoplasmic Transport Proteins - metabolism; Plant Genetics and Genomics; RNA, Messenger - metabolism; RNA-Binding Proteins - chemistry; RNA-Binding Proteins - metabolism; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - chemistry; Saccharomyces cerevisiae Proteins - metabolism; Nuclear pore; Nuclear import; Importin; Nab2; Nuclear localization signal; Karyopherin; Nucleocytoplasmic transport
• ISSN: 1345-711X; 1570-0267; 1570-0267
• DOI: 10.1007/s10969-013-9150-1

Import-Karyopherin or Importin proteins bind nuclear localization signals (NLSs) to mediate the import of proteins into the cell nucleus. Karyopherin β2 or Kapβ2, also known as Transportin, is a member of this transporter family responsible for the import of numerous RNA binding proteins. Kapβ2 recognizes a targeting signal termed the PY-NLS that lies within its cargos to target them through the nuclear pore complex. The recognition of PY-NLS by Kapβ2 is conserved throughout eukaryotes. Kap104, the Kapβ2 homolog in Saccharomyces cerevisiae , recognizes PY-NLSs in cargos Nab2, Hrp1, and Tfg2. We have determined the crystal structure of Kapβ2 bound to the PY-NLS of the mRNA processing protein Nab2 at 3.05-Å resolution. A seven-residue segment of the PY-NLS of Nab2 is observed to bind Kapβ2 in an extended conformation and occupies the same PY-NLS binding site observed in other Kapβ2·PY-NLS structures.