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2pnh
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Collapsed DNA replication forks must be reactivated through | + | Collapsed DNA replication forks must be reactivated through origin-independent reloading of the replication machinery (replisome) to ensure complete duplication of cellular genomes. In E. coli, the PriA-dependent pathway is the major replication restart mechanism and requires primosome proteins PriA, PriB, and DnaT for replisome reloading. However, the molecular mechanisms that regulate origin-independent replisome loading are not fully understood. Here, we demonstrate that assembly of primosome protein complexes represents a key regulatory mechanism, as inherently weak PriA-PriB and PriB-DnaT interactions are strongly stimulated by single-stranded DNA. Furthermore, the binding site on PriB for single-stranded DNA partially overlaps the binding sites for PriA and DnaT, suggesting a dynamic primosome assembly process in which single-stranded DNA is handed off from one primosome protein to another as a repaired replication fork is reactivated. This model helps explain how origin-independent initiation of DNA replication is restricted to repaired replication forks, preventing overreplication of the genome. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Keck, J | + | [[Category: Keck, J L.]] |
| - | [[Category: Lopper, M | + | [[Category: Lopper, M E.]] |
[[Category: beta barrel]] | [[Category: beta barrel]] | ||
[[Category: dna binding protein]] | [[Category: dna binding protein]] | ||
[[Category: ob fold]] | [[Category: ob fold]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:31:17 2008'' |
Revision as of 16:31, 21 February 2008
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Escherichia coli PriB E39A variant
Overview
Collapsed DNA replication forks must be reactivated through origin-independent reloading of the replication machinery (replisome) to ensure complete duplication of cellular genomes. In E. coli, the PriA-dependent pathway is the major replication restart mechanism and requires primosome proteins PriA, PriB, and DnaT for replisome reloading. However, the molecular mechanisms that regulate origin-independent replisome loading are not fully understood. Here, we demonstrate that assembly of primosome protein complexes represents a key regulatory mechanism, as inherently weak PriA-PriB and PriB-DnaT interactions are strongly stimulated by single-stranded DNA. Furthermore, the binding site on PriB for single-stranded DNA partially overlaps the binding sites for PriA and DnaT, suggesting a dynamic primosome assembly process in which single-stranded DNA is handed off from one primosome protein to another as a repaired replication fork is reactivated. This model helps explain how origin-independent initiation of DNA replication is restricted to repaired replication forks, preventing overreplication of the genome.
About this Structure
2PNH is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
A hand-off mechanism for primosome assembly in replication restart., Lopper M, Boonsombat R, Sandler SJ, Keck JL, Mol Cell. 2007 Jun 22;26(6):781-93. PMID:17588514
Page seeded by OCA on Thu Feb 21 18:31:17 2008
