Nuclear export of proteins with leucine-rich nuclear export signals (NES) in vivo and in vitro

• Antragstellerin: Professorin Dr. Marie-Christine Dabauvalle
• Fachliche Zuordnung: Zellbiologie
• Förderung: Förderung von 2000 bis 2007
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 5239500

Nuclear export of proteins with leucine-rich nuclear export signals (NES) is mediated by the export receptor CRM1/exportin1. However, additional protein factors interacting with leucine-rich NESs have been described. In particular the eukaryotic initiation factor eIF-5A has recently been shown to be a critical cellular cofactor for the nuclear export of the NES-containing HIV-1 Rev protein. By microinjection of export substrates in combination with specific inhibitors and antibodies into the nucleus of Xenopus oocytes we wish to clarify whether eIF-5A is also involved in the export of other NES-proteins. By performing in vitro binding studies (overlay assay) we have already identified several pore complex proteins to which eIF-5A binds. We now plan to molecularly characterize two additional binding partners and to establish a cell-free system for the further analysis of nuclear export processes. Recently we made the surprising observation that nuclear actin is involved in export processes and located at the inner pore complex filaments. We now wish to analyze in more detail the functional role of nuclear actin in export processes and the mode of interactions with transport complexes.

• DFG-Verfahren: Schwerpunktprogramme
• Teilprojekt zu: SPP 1050: Funktionelle Architektur des Zellkerns