Switching of metabolic programs in response to light availability is an essential function of the cyanobacterial circadian output pathway.
Elife
; 62017 04 21.
Article
en En
| MEDLINE
| ID: mdl-28430105
ABSTRACT
The transcription factor RpaA is the master regulator of circadian transcription in cyanobacteria, driving genome-wide oscillations in mRNA abundance. Deletion of rpaA has no effect on viability in constant light conditions, but renders cells inviable in cycling conditions when light and dark periods alternate. We investigated the mechanisms underlying this viability defect, and demonstrate that the rpaA- strain cannot maintain appropriate energy status at night, does not accumulate carbon reserves during the day, and is defective in transcription of genes crucial for utilization of carbohydrate stores at night. Reconstruction of carbon utilization pathways combined with provision of an external carbon source restores energy charge and viability of the rpaA- strain in light/dark cycling conditions. Our observations highlight how a circadian output pathway controls and temporally coordinates essential pathways in carbon metabolism to maximize fitness of cells facing periodic energy limitations.
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Regulación Bacteriana de la Expresión Génica
/
Ritmo Circadiano
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Cianobacterias
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Metabolismo Energético
Idioma:
En
Revista:
Elife
Año:
2017
Tipo del documento:
Article
País de afiliación:
Estados Unidos