Transcriptional architecture and chromatin landscape of the core circadian clock in mammals.
Science
; 338(6105): 349-54, 2012 Oct 19.
Article
em En
| MEDLINE
| ID: mdl-22936566
ABSTRACT
The mammalian circadian clock involves a transcriptional feed back loop in which CLOCK and BMAL1 activate the Period and Cryptochrome genes, which then feedback and repress their own transcription. We have interrogated the transcriptional architecture of the circadian transcriptional regulatory loop on a genome scale in mouse liver and find a stereotyped, time-dependent pattern of transcription factor binding, RNA polymerase II (RNAPII) recruitment, RNA expression, and chromatin states. We find that the circadian transcriptional cycle of the clock consists of three distinct phases a poised state, a coordinated de novo transcriptional activation state, and a repressed state. Only 22% of messenger RNA (mRNA) cycling genes are driven by de novo transcription, suggesting that both transcriptional and posttranscriptional mechanisms underlie the mammalian circadian clock. We also find that circadian modulation of RNAPII recruitment and chromatin remodeling occurs on a genome-wide scale far greater than that seen previously by gene expression profiling.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Transcrição Gênica
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Cromatina
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Ativação Transcricional
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Epigênese Genética
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Criptocromos
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Relógios Circadianos
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Fígado
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article