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Validation of a Mouse Model to Disrupt LINC Complexes in a Cell-specific Manner
Published on: December 10, 2015
A lattice model of the nuclear pore complex
Stephen G Brohawn1, Thomas U Schwartz
1Department of Biology; Massachusetts Institute of Technology; Cambridge, MA USA.
Communicative & Integrative Biology
|July 31, 2009
Summary
Researchers discovered a shared protein element, ACE1, between the nuclear pore complex (NPC) and vesicle coats. This finding provides the first evidence that the NPC and vesicle coats evolved from a common ancestor, supporting a lattice model for NPC assembly.
Area of Science:
- Cell Biology
- Structural Biology
- Evolutionary Biology
Background:
- The nuclear pore complex (NPC) is a large protein machine regulating transport between the nucleus and cytoplasm in eukaryotes.
- The NPC scaffold comprises architectural proteins and phenylalanine-glycine (FG) repeat proteins forming the transport barrier.
Purpose of the Study:
- To elucidate the molecular architecture of the NPC by solving the structure of nucleoporin 85 (Nup85) in complex with Seh1.
- To investigate the evolutionary origins of the NPC and vesicle coats.
Main Methods:
- X-ray crystallography to determine the structure of the Nup85-Seh1 complex.
- Bioinformatic analysis and functional site prediction based on protein element homology.
- Experimental verification of predicted functional sites.
Main Results:
- Defined a novel tripartite protein element, ancestral coatomer element (ACE1), shared by Nup85 and vesicle coat proteins.
- Provided the first experimental evidence for the common evolutionary origin of the NPC and vesicle coats.
- Proposed a lattice model for NPC assembly, analogous to vesicle coat structures.
Conclusions:
- The NPC and vesicle coats share a common evolutionary ancestor, indicated by the conserved ACE1 protein element.
- The NPC scaffold may be a polygonal network forming a molecular lattice, facilitating the assembly of nucleoporins.
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