Synergistic transcriptional activation by CTF/NF-I and the estrogen receptor involves stabilized interactions with a limiting target factor.


Autoria(s): Martinez E.; Dusserre Y.; Wahli W.; Mermod N.
Data(s)

01/06/1991

Resumo

Transcription initiation at eukaryotic protein-coding gene promoters is regulated by a complex interplay of site-specific DNA-binding proteins acting synergistically or antagonistically. Here, we have analyzed the mechanisms of synergistic transcriptional activation between members of the CCAAT-binding transcription factor/nuclear factor I (CTF/NF-I) family and the estrogen receptor. By using cotransfection experiments with HeLa cells, we show that the proline-rich transcriptional activation domain of CTF-1, when fused to the GAL4 DNA-binding domain, synergizes with each of the two estrogen receptor-activating regions. Cooperative DNA binding between the GAL4-CTF-1 fusion and the estrogen receptor does not occur in vitro, and in vivo competition experiments demonstrate that both activators can be specifically inhibited by the overexpression of a proline-rich competitor, indicating that a common limiting factor is mediating their transcriptional activation functions. Furthermore, the two activators functioning synergistically are much more resistant to competition than either factor alone, suggesting that synergism between CTF-1 and the estrogen receptor is the result of a stronger tethering of the limiting target factor(s) to the two promoter-bound activators.

Identificador

http://serval.unil.ch/?id=serval:BIB_BD22DD3F60F6

isbn:0270-7306[print], 0270-7306[linking]

pmid:2038313

isiid:A1991FM85200003

Idioma(s)

en

Fonte

Molecular and Cellular Biology, vol. 11, no. 6, pp. 2937-2945

Palavras-Chave #CCAAT-Enhancer-Binding Proteins; Chloramphenicol O-Acetyltransferase/genetics; Chloramphenicol O-Acetyltransferase/metabolism; DNA-Binding Proteins/metabolism; Gene Expression Regulation; Hela Cells/physiology; Humans; Kinetics; Models, Genetic; NFI Transcription Factors; Nuclear Proteins; Plasmids; Proline; Promoter Regions, Genetic; Receptors, Estrogen/metabolism; Restriction Mapping; Transcription Factors; Transcription, Genetic; Transfection; Y-Box-Binding Protein 1
Tipo

info:eu-repo/semantics/article

article