RNA-binding as chaperones of DNA binding proteins from starved cells.
Biochem Biophys Res Commun
; 524(2): 484-489, 2020 04 02.
Article
en En
| MEDLINE
| ID: mdl-32007271
DNA-binding proteins from starved cells (Dps) in Escherichia coli protects DNA from multiple stresses during the stationary phase by forming a stable Dps-DNA complex. In contrast, Dps cannot bind to DNA during the exponential phase and it has not been clear why Dps conditionally binds to DNA depending on the growth phase. In this study, we show that DNA-free Dps in the exponential phase can also bind to RNA and the preemptive binding of RNA precludes DNA from interacting with Dps. The critical role of RNA in modulating the stability and functional competence of Dps and their morphology, leads us to propose a two-state model of Dps in executing stress responses. In the exponential phase, Dps is present predominantly as ribonucleoprotein complex. Under starvation, RNAs are degraded by up-regulated RNases, activating Dps to bind with chromosomal DNAs protecting them from diverse stresses. A dual role of RNA as an inhibitor of DNA binding and chaperone to keep dynamic functional status of Dps would be crucial for operating an immediate protection of chromosomal DNAs on starvation. The holdase-type chaperoning role of RNA in Dps-mediated stress responses would shed light on the role of RNAs as chaperone (Chaperna).
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
ARN Bacteriano
/
Proteínas de Escherichia coli
/
Proteínas de Unión al ADN
/
Escherichia coli
Límite:
Humans
Idioma:
En
Revista:
Biochem Biophys Res Commun
Año:
2020
Tipo del documento:
Article
Pais de publicación:
Estados Unidos