Assembly and Structure of the symmetric core of the Nuclear Pore Complex

• Applicant: Dr. Tobias Stuwe
• Subject Area: Structural Biology
• Term: from 2013 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 244311388

The nuclear pore complex (NPC) is a massive (~120 million Dalton in vertebrates) supramolecular assembly composed of ~30 different proteins that are organized into several subcomplexes. The highly symmetrical core of the NPC contains multiple copies of each subcomplex, thus accounting for ~1,000 protein molecules in the vertebrate NPC. As the sole mediator of macromolecular transport across the nuclear envelope, the NPC adopts a pivotal role in cellular physiology, which becomes evident in many oncogenic and developmental defects caused by impaired NPC function. Although fundamental aspects of the NPC architecture have been known for decades, its detailed structure has largely remained elusive, primarily due to the flexibility and heterogeneity of isolated, purified NPCs. An alternative approach is to assemble the NPC from crystal structures of individual components and their interactions to obtain a pseudo-atomic model for the entire NPC. Larger assemblies will be assembled with the help of cryo-electron microscopy. The aim of this proposal is the development of an in vitro reconstitution system for the entire symmetric NPC core and the structure determination of key building blocks of the NPC. The expression systems for all 18 nucleoporins of the symmetric NPC core, as well as the crystallization of key subcomplexes, has already been achieved prior to this proposal. The results from these crystal structures are likely to yield key insight into the architecture and structural principles of the NPC and other known membrane coats.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professor André Hoelz, Ph.D.