DnaA-DnaB-DnaC complex
A protein-DNA complex consisting of the helicase loading complex DnaB-DnaC bound to the DNA-bound DNA replication initiation protein DnaA. Essential for DNA replication initiation. [GO:1990157]
Has part: DnaB-DnaC complex (GO:1990100)
Components
| Component | Type | Part of / acts on | Grounding | Genes | Stoichiometry | Essential | Role |
|---|---|---|---|---|---|---|---|
| DnaB-DnaC complex | Protein complex | part of | GO:1990100 | UNKNOWN | Helicase-loading subcomplex bound to DnaA on origin DNA.
| ||
| DnaA replication initiation protein | Protein | part of | Reviewed label only (reviewed name; no accession asserted) | dnaA | UNKNOWN | DNA-bound initiator constituent that recruits the DnaB-DnaC helicase-loading complex to origin DNA.
| |
| chromosomal origin DNA | Dna | part of | Reviewed label only (reviewed name; no accession asserted) | UNKNOWN | Origin DNA scaffold bound by DnaA during DnaB-DnaC helicase loading.
|
Taxonomic distribution
NCBITaxon:562Escherichia coli — COMMON: Makowska-Grzyska and Kaguni 2010 studied DnaB-DnaC loading and DnaC release at the E. coli chromosomal origin. [PMID:20129058]
Canonical examples
NCBITaxon:562Escherichia coli — Makowska-Grzyska and Kaguni 2010 used an E. coli oriC initiation system to examine a DnaA-bound DnaB-DnaC prepriming intermediate. [PMID:20129058]
Functions
- DNA replication initiation
GO:0006270— The DnaA-DnaB-DnaC complex participates in DNA replication initiation by placing the DnaB-DnaC helicase-loading subcomplex on DnaA-bound origin DNA.GO:1990157GO:1990157 defines the DnaA-DnaB-DnaC complex as essential for DNA replication initiation.GO:0006270GO:0006270 is the Gene Ontology biological-process term for DNA replication initiation.
Mechanism graphs
DnaA-DnaB-DnaC supports initiation (FUNCTION)
A DnaB-DnaC helicase-loading subcomplex binds DnaA on origin DNA to form a pre-primosome used in DNA replication initiation.
| Subject | Predicate | Object | Evidence |
|---|---|---|---|
| DnaB-DnaC complex | contributes to | DnaA-DnaB-DnaC complex |
|
| DnaA replication initiation protein | contributes to | DnaA-DnaB-DnaC complex |
|
| chromosomal origin DNA | scaffolds | DnaA-DnaB-DnaC complex |
|
| DnaA-DnaB-DnaC complex | supports | DNA replication initiation |
|
Discussions
- CURATION_TODO (OPEN): Resolve exact source-neutral DnaA and chromosomal origin DNA groundings for the DnaA-DnaB-DnaC complex. GO:1990157 defines DNA-bound DnaA and associated DNA as constituents of this pre-primosome. Exact source-neutral InterPro, Pfam, NCBIfam, UniProt family or SO sequence-feature CURIEs for these components need narrower curation before the labels can be grounded.
- INTERPRETATION (RESOLVED): Leave DnaG primase, DnaC-release mechanics and replication-restart proteins out of the GO:1990157 DnaA-DnaB-DnaC complex. GO:1990157 denotes the DnaA-bound DnaB-DnaC pre-primosome. GO models DnaG-containing primase-helicase entities and PriA/PriB/DnaT restart assemblies as separate sibling terms rather than as constituents of this complex.
Evidence
GO:1990157Gene Ontology cellular-component term for the DnaA-DnaB-DnaC complex.GO:1990099OLS reports GO:1990099 pre-primosome complex as the direct GO:1990157 is-a parent.GO:1990100Gene Ontology cellular-component term for the DnaB-DnaC helicase-loading subcomplex.GO:0006270Gene Ontology biological-process term for DNA replication initiation.PMID:20129058PubMed identifier for Makowska-Grzyska and Kaguni 2010, the Molecular Cell paper cited by GO:1990157.DOI:10.1016/j.molcel.2009.12.031DOI for Makowska-Grzyska and Kaguni 2010, 'Primase directs the release of DnaC from DnaB', as reported by PubMed.
Curation history
2026-10-01T05:44:40Zcodex · CREATED_RECORD — Scaffolded by scripts/new_record.py2026-10-01T05:46:05Zcodex · EXPANDED_RECORD — Added pre-primosome parentage, the DnaB-DnaC subcomplex plus DnaA and origin-DNA components, E. coli oriC evidence, DNA-replication-initiation function evidence, GO/PubMed/DOI evidence, a nonmechanistic initiation graph, and grounding/boundary discussions.