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Published on: December 10, 2015
Nup53 is required for nuclear envelope and nuclear pore complex assembly.
Lisa A Hawryluk-Gara1, Melpomeni Platani, Rachel Santarella
1Department of Cell Biology, University of Alberta, Edmonton, AB, Canada.
Molecular Biology of the Cell
|February 8, 2008
Summary
Nuclear pore complex (NPC) assembly and nuclear envelope (NE) formation require the nucleoporin Nup53. A specific Nup53-Nup155 complex region is crucial for reconstituting NPC and NE assembly processes.
Area of Science:
- Cell Biology
- Molecular Biology
- Structural Biology
Background:
- Nuclear pore complexes (NPCs) regulate transport across the nuclear envelope (NE).
- NPCs are built from multiple protein subcomplexes with eightfold symmetry.
- A conserved subcomplex includes nucleoporins Nup53 and Nup155.
Purpose of the Study:
- To define Nup53 regions involved in nucleoporin binding and NPC targeting.
- To investigate the role of Nup53 in nuclear envelope and NPC assembly.
- To understand the contribution of the Nup53-Nup155 interaction to assembly.
Main Methods:
- Truncation analysis of Nup53 to identify functional domains.
- In vivo studies using Xenopus egg extracts for NE and NPC assembly assays.
- Biochemical assays to study Nup53-Nup155 binding.
Main Results:
- Defined Nup53 regions responsible for binding to neighboring nucleoporins and NPC targeting.
- Demonstrated that Nup53 is essential for both NE and NPC assembly in Xenopus egg extracts.
- Showed that Nup53-depleted extracts could be rescued by a Nup53 fragment binding Nup155.
Conclusions:
- Nup53 plays a critical role in nuclear envelope and nuclear pore complex assembly.
- The interaction between Nup53 and Nup155 is vital for these assembly processes.
- Formation of the Nup53-Nup155 complex is proposed as a key event in NE and NPC assembly.
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