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Updated: Jun 19, 2026
10:23
Self-assembly of Complex Two-dimensional Shapes from Single-stranded DNA Tiles
Published on: May 8, 2015
Bacterial origin recognition complexes direct assembly of higher-order DnaA oligomeric structures
Diana T Miller1, Julia E Grimwade, Thu Betteridge
1Department of Biological Sciences, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901, USA.
Summary
The bacterial origin recognition complex (ORC) is crucial for assembling replication initiation complexes in Escherichia coli. It facilitates the binding of initiator proteins to low-affinity sites, ensuring proper DNA replication.
Area of Science:
- Molecular Biology
- Microbiology
- Genetics
Background:
- Eukaryotic origin recognition complexes (ORCs) regulate DNA replication initiation by binding to origins and forming prereplication complexes (pre-RCs).
- Escherichia coli possesses a similar nucleoprotein complex involving the initiator protein DnaA at its origin of replication, oriC.
Purpose of the Study:
- To investigate the functional role of the bacterial ORC in Escherichia coli.
- To determine if the bacterial ORC mediates low-affinity DnaA-oriC interactions during pre-RC assembly.
Main Methods:
- Investigated the functional role of the bacterial ORC in Escherichia coli.
- Examined the mediation of low-affinity DnaA-oriC interactions during pre-RC assembly.
Main Results:
- The E. coli ORC is essential for DnaA protein binding to low-affinity sites within oriC.
- ORC-mediated assistance is primarily directed towards proximal weak sites.
- This process requires DnaA protein that is proficient in oligomerization.
Conclusions:
- Bacterial ORC plays a critical role in facilitating the loading of DnaA onto low-affinity sites, a key step in prokaryotic pre-RC assembly.
- DnaA oligomers, emerging from high-affinity sites, extend to weak sites with the assistance of ORC, enabling efficient replication initiation.
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