Direct single-cell observation of a key Escherichia coli cell-cycle oscillator.
Sci Adv
; 10(29): eado5398, 2024 Jul 19.
Article
in En
| MEDLINE
| ID: mdl-39018394
ABSTRACT
Initiation of DNA replication in Escherichia coli is coupled to cell size via the DnaA protein, whose activity is dependent on its nucleotide-bound state. However, the oscillations in DnaA activity have never been observed at the single-cell level. By measuring the volume-specific production rate of a reporter protein under control of a DnaA-regulated promoter, we could distinguish two distinct cell-cycle oscillators. The first, driven by both DnaA activity and SeqA repression, shows a causal relationship with cell size and divisions, similarly to initiation events. The second one, a reporter of DnaA activity alone, loses the synchrony and causality properties. Our results show that transient inhibition of gene expression by SeqA keeps the oscillation of volume-sensing DnaA activity in phase with the subsequent division event and suggest that DnaA activity peaks do not correspond directly to initiation events.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Gene Expression Regulation, Bacterial
/
Cell Cycle
/
Escherichia coli Proteins
/
Escherichia coli
/
Single-Cell Analysis
Language:
En
Journal:
Sci Adv
Year:
2024
Document type:
Article
Affiliation country:
Country of publication: