Circadian programs of transcriptional activation, signaling, and protein turnover revealed by microarray analysis of mammalian cells.
Curr Biol
; 12(7): 551-7, 2002 Apr 02.
Article
em En
| MEDLINE
| ID: mdl-11937023
ABSTRACT
Many aspects of physiology and behavior are temporally organized into daily 24 hr rhythms, driven by an endogenous circadian clock. Studies in eukaryotes have identified a network of interacting genes forming interlocked autoregulatory feedback loops which underlie overt circadian organization in single cells. While in mammals the master oscillator resides in the suprachiasmatic nuclei of the hypothalamus, semiautonomous circadian oscillators also exist in peripheral tissues and in immortalized fibroblasts, where rhythmicity is induced following a serum shock. We used this model system in combination with high-density cDNA microarrays to examine the magnitude and quality of clock control of gene expression in mammalian cells. Supported by application of novel bioinformatics tools, we find approximately 2% of genes, including expected canonical clock genes, to show consistent rhythmic circadian expression across five independent experiments. Rhythmicity in most of these genes is novel, and they fall into diverse functional groups, highlighted by a predominance of transcription factors, ubiquitin-associated factors, proteasome components, and Ras/MAPK signaling pathway components. When grouped according to phase, 68% of the genes were found to peak during estimated subjective day, 32% during estimated subjective night, with a tendency to peak at a phase corresponding to anticipation of dawn or dusk.
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Base de dados:
MEDLINE
Assunto principal:
Relógios Biológicos
/
Proteínas
/
Ativação Transcricional
/
Ritmo Circadiano
/
Sistema de Sinalização das MAP Quinases
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Curr Biol
Assunto da revista:
BIOLOGIA
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
Estados Unidos