Single-molecule dynamics of enhanceosome assembly in embryonic stem cells.
Cell
; 156(6): 1274-1285, 2014 Mar 13.
Article
em En
| MEDLINE
| ID: mdl-24630727
ABSTRACT
Enhancer-binding pluripotency regulators (Sox2 and Oct4) play a seminal role in embryonic stem (ES) cell-specific gene regulation. Here, we combine in vivo and in vitro single-molecule imaging, transcription factor (TF) mutagenesis, and ChIP-exo mapping to determine how TFs dynamically search for and assemble on their cognate DNA target sites. We find that enhanceosome assembly is hierarchically ordered with kinetically favored Sox2 engaging the target DNA first, followed by assisted binding of Oct4. Sox2/Oct4 follow a trial-and-error sampling mechanism involving 84-97 events of 3D diffusion (3.3-3.7 s) interspersed with brief nonspecific collisions (0.75-0.9 s) before acquiring and dwelling at specific target DNA (12.0-14.6 s). Sox2 employs a 3D diffusion-dominated search mode facilitated by 1D sliding along open DNA to efficiently locate targets. Our findings also reveal fundamental aspects of gene and developmental regulation by fine-tuning TF dynamics and influence of the epigenome on target search parameters.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
DNA
/
Elementos Facilitadores Genéticos
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Fator 3 de Transcrição de Octâmero
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Células-Tronco Embrionárias
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Fatores de Transcrição SOXB1
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Análise de Célula Única
Limite:
Animals
Idioma:
En
Revista:
Cell
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Estados Unidos