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C-terminal binding proteins (CtBPs) attenuate KLF4-mediated transcriptional activation.

ABSTRACT: We aimed to examine the physical interaction between CtBPs and KLF4 and the potential importance of this interaction. Co-immunoprecipitation indicated that CtBP1 indeed interacted with KLF4. This was supported by the co-localization of both KLF4 and CtBP1 in the promoter regions of KLF4 downstream target genes. In addition, overexpression of CtBP1 significantly decreased KLF4-mediated transcriptional activation in both an artificial (pGL5) and genuine (IAP and Keratin-4) reporter system. Mutations in the potential CtBP binding motif in KLF4 were accompanied by loss of the inhibitory effect of CtBP1 in the reporter assay and of the physical interaction with CtBP1. Overall, our results suggest that CtBPs attenuate KLF4-mediated transcriptional activation through the physical interaction with KLF4.

SUBMITTER: Liu G

PROVIDER: S-EPMC2766794 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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C-terminal binding proteins (CtBPs) attenuate KLF4-mediated transcriptional activation.

Liu Gang G Zheng Hai H Ai Walden W

FEBS letters 20090912 19

We aimed to examine the physical interaction between CtBPs and KLF4 and the potential importance of this interaction. Co-immunoprecipitation indicated that CtBP1 indeed interacted with KLF4. This was supported by the co-localization of both KLF4 and CtBP1 in the promoter regions of KLF4 downstream target genes. In addition, overexpression of CtBP1 significantly decreased KLF4-mediated transcriptional activation in both an artificial (pGL5) and genuine (IAP and Keratin-4) reporter system. Mutatio ...[more]

PMID: 19751731

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