Simulations of stressosome activation emphasize allosteric interactions between RsbR and RsbT.
BMC Syst Biol
; 7: 3, 2013 Jan 15.
Article
en En
| MEDLINE
| ID: mdl-23320651
ABSTRACT
BACKGROUND:
The stressosome is a bacterial signalling complex that responds to environmental changes by initiating a protein partner switching cascade, which leads to the release of the alternative sigma factor, σB. Stress perception increases the phosphorylation of the stressosome sensor protein, RsbR, and the scaffold protein, RsbS, by the protein kinase, RsbT. Subsequent dissociation of RsbT from the stressosome activates the σB cascade. However, the sequence of physical events that occur in the stressosome during signal transduction is insufficiently understood.RESULTS:
Here, we use computational modelling to correlate the structure of the stressosome with the efficiency of the phosphorylation reactions that occur upon activation by stress. In our model, the phosphorylation of any stressosome protein is dependent upon its nearest neighbours and their phosphorylation status. We compare different hypotheses about stressosome activation and find that only the model representing the allosteric activation of the kinase RsbT, by phosphorylated RsbR, qualitatively reproduces the experimental data.CONCLUSIONS:
Our simulations and the associated analysis of published data support the following hypotheses (i) a simple Boolean model is capable of reproducing stressosome dynamics, (ii) different stressors induce identical stressosome activation patterns, and we also confirm that (i) phosphorylated RsbR activates RsbT, and (ii) the main purpose of RsbX is to dephosphorylate RsbS-P.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Estrés Fisiológico
/
Proteínas Bacterianas
/
Transducción de Señal
/
Modelos Moleculares
/
Modelos Biológicos
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
BMC Syst Biol
Asunto de la revista:
BIOLOGIA
/
BIOTECNOLOGIA
Año:
2013
Tipo del documento:
Article
País de afiliación:
Alemania