NLS-indepedent nucleocytoplasmic transport pathways of macromolecules

• Applicant: Professor Dr. Gabriel Schlenstedt
• Subject Area: Biochemistry
• Term: from 1998 to 2007
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5106782

Transport of macromolecules between the cytoplasm and the nucleus across the nuclear envelope occurs through the nuclear pore complex (NPC). Transport substrates bind to soluble receptors and subsequently pass the NPC by an energy- and Ran-dependent mechanism. The Ran GTPase regulates association and dissociation of the substrates with the receptors. The best understood transport pathway is the import of nuclear localization signal (NLS)-containing proteins into the nucleus. The NLS-receptor consists of two subunits (importin-alpha and beta). Other, more specialized transport pathways are not importin-dependent. Ribosomal proteins directly bind to various importinbeta-related receptors. The aim of this project is to investigate nuclear import of ribosomal proteins in general and to analyze the role of importin-beta-related receptors in ribosomal protein import in vivo and in vitro. Another goal is the functional characterization of several novel importin-beta-related receptors. Here, we focus on the identification of the respective transport substrates.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1050: Funktionelle Architektur des Zellkerns