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Purification and Quality Control of Recombinant Septin Complexes for Cell-Free Reconstitution
Published on: June 23, 2022
The Caenorhabditis elegans septin complex is nonpolar.
Corinne M John1, Richard K Hite, Christine S Weirich
1Institute of Biochemistry, ETH Zürich, Zürich, Switzerland.
The EMBO Journal
|June 30, 2007
Summary
Septins are essential GTPases for cell division. This study reveals the Caenorhabditis elegans septin core complex is a symmetric heterotetramer, suggesting septin filaments are nonpolar.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Septins are conserved GTPases crucial for cell division and polarity.
- Septin complexes typically form around a tetrameric core, but its structure and polarity influence are poorly understood.
Purpose of the Study:
- To elucidate the molecular structure of the Caenorhabditis elegans septin core complex.
- To determine the polarity of septin complexes and filaments.
Main Methods:
- Purification and characterization of the UNC-59/UNC-61 septin complex.
- Electron microscopy of the heterotetramer and GFP-tagged variants.
- Analysis of subunit arrangement and filament polarity.
Main Results:
- The Caenorhabditis elegans septin core complex consists of UNC-59 and UNC-61 forming a dimer of heterodimers (heterotetramer).
- Electron microscopy revealed a linear arrangement of the four subunits.
- N-terminal GFP fusions indicated a UNC-59/UNC-61/UNC-61/UNC-59 subunit sequence.
- C-terminal extensions suggest lateral protrusion from the core.
Conclusions:
- The septin core complex is symmetric.
- Septin filaments likely form in a nonpolar manner.
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