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Published on: February 5, 2015
Correlation between ribonucleoside-diphosphate reductase and three replication proteins in Escherichia coli
M Antonia Sánchez-Romero1, Felipe Molina, Alfonso Jiménez-Sánchez
1Departamento de Bioquímica y Biología Molecular y Genética, Universidad de Extremadura, E06080 Badajoz, Spain.
BMC Molecular Biology
|January 28, 2010
Summary
Ribonucleotide reductase (RNR) protein NrdB localizes to replication clusters, supporting the replication hyperstructure model. This finding links RNR directly to DNA replication forks.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Evidence suggests a close link between ribonucleotide reductase (RNR) and DNA replication machinery.
- The replication hyperstructure hypothesis proposes this close association.
- Recent findings challenged this by suggesting even NrdB distribution.
Purpose of the Study:
- To investigate the subcellular localization of RNR protein NrdB.
- To determine the relationship between NrdB and other replication proteins.
Main Methods:
- NrdB protein was tagged with a 3xFLAG epitope.
- Subcellular localization was determined using immunofluorescence microscopy.
- Colocalization and interfoci distances with replication proteins (SeqA, DnaB, DnaX) were analyzed.
Main Results:
- NrdB localizes to nucleoid-associated clusters during replication.
- The number of NrdB foci correlates with replication fork numbers and decreases post-replication.
- NrdB foci numbers and distances to other replication proteins (SeqA, DnaB, DnaX) are highly similar.
Conclusions:
- NrdB forms clusters associated with the nucleoid during DNA replication.
- These clusters are transient, disappearing after replication.
- Results strongly support NrdB's close association with the replication machinery at the fork, validating the replication hyperstructure model.
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