Control of eukaryotic gene expression: gene loops and transcriptional memory.
Adv Enzyme Regul
; 51(1): 118-25, 2011.
Article
em En
| MEDLINE
| ID: mdl-21036187
ABSTRACT
Gene loops are dynamic structures that juxtapose promoterterminator regions of Pol II-transcribed genes. Although first described in yeast, gene loops have now been identified in yeast and mammalian cells. Looping requires components of the transcription preinitiation complex, the pre-mRNA 30-end processing machinery, and subunits of the nuclear pore complex. Loop formation is transcription-dependent, but neither basal nor activated transcription requires looping. Rather, looping appears to affect cellular memory of recent transcriptional activity, enabling a more rapid response to subsequent stimuli. The nuclear pore has been implicated in both memory and looping. Our working model is that loops are formed and/or maintained at the nuclear pore to facilitate hand-off of Pol II form the terminator to the promoter, thereby bypassing Pol II recruitment as the rate-limiting step in reactivation of transcription. Involvement of the nuclear pore also suggests that looping might facilitate mRNA export to the cytoplasm. The technology now exists to test these ideas.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Transcrição Gênica
/
Expressão Gênica
/
Ativação Transcricional
/
Conformação de Ácido Nucleico
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article