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Monitoring eIF4F Assembly by Measuring eIF4E-eIF4G Interaction in Live Cells
Published on: May 1, 2020
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Assembly of eIF3 Mediated by Mutually Dependent Subunit Insertion
M Duane Smith1, Luisa Arake-Tacca2, Adam Nitido1
1Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.
Structure (London, England : 1993)
|May 24, 2016
Summary
Eukaryotic initiation factor 3 (eIF3) subunits assemble dependently, primarily via a helical bundle. Dysregulated eIF3 subunit expression in cancer may lead to altered complexes, contributing to disease.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Eukaryotic initiation factor 3 (eIF3) is a crucial multi-protein complex regulating translation initiation.
- While eIF3's overall structure is known, its assembly mechanism and the impact of subunit dysregulation in cancer remain unclear.
Purpose of the Study:
- To elucidate the assembly mechanism of the human eIF3 complex.
- To investigate the structural consequences of eIF3 subunit expression dysregulation in cancer.
Main Methods:
- Analysis of interdependent subunit assembly.
- Identification of key structural features governing eIF3 formation, including PCI-MPN domains and helical bundles.
Main Results:
- eIF3 subunits assemble in an interdependent manner.
- A helical bundle formed by C-terminal helices from PCI-MPN domains is central to eIF3 assembly.
- A minimal functional eIF3 subcomplex comprises subunits a, b, c, f, g, i, and m.
Conclusions:
- The assembly of eIF3 is an interdependent process driven by specific structural interactions.
- Aberrant eIF3 subcomplexes arising from subunit overexpression or underexpression are implicated in cancer development.
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