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Updated: Sep 19, 2025
06:39
Live Cell Imaging of Chromosome Segregation During Mitosis
Published on: March 14, 2018
9.5K
Archaeal SegAB forms a bipolar structure that promotes chromosome segregation in spherical cells
Arthur Charles-Orszag1,2, Samuel J Lord1, Nadia Herrera3
1Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA, USA.
Biorxiv : the Preprint Server for Biology
|June 6, 2025
Summary
Archaeal SegA and SegB proteins cooperate to segregate chromosomes, forming a unique bipolar structure distinct from bacterial systems. This study reveals the SegAB mechanism in Sulfolobus acidocaldarius.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Archaeal chromosome segregation mechanisms are poorly understood.
- SegAB operons are implicated in segregation, but their function is unclear.
Purpose of the Study:
- To elucidate the mechanism of chromosome segregation by SegA and SegB proteins in Sulfolobus acidocaldarius.
- To investigate the interaction between SegA and SegB during cell division.
Main Methods:
- Comparative genomics
- Structural biology
- Genetic knockouts
- Quantitative cell biology
- In vitro DNA binding assays
Main Results:
- SegB binds centromeric DNA and localizes to segregating chromosomes.
- SegA, a ParA-like ATPase, compacts and segregates DNA.
- SegA forms a dynamic structure between SegB foci during division.
- SegA localization is dependent on SegB.
Conclusions:
- SegA and SegB form a novel bipolar DNA-segregating structure in archaea.
- The SegAB system differs significantly from bacterial ParABS segregation mechanisms.
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