TY - JOUR
T1 - SRC Proximal and Core Promoter Elements Dictate TAF1 Dependence and Transcriptional Repression by Histone Deacetylase Inhibitors
AU - Dehm, Scott M.
AU - Hilton, Traci L.
AU - Wang, Edith H.
AU - Bonham, Keith
PY - 2004/3
Y1 - 2004/3
N2 - Histone deacetylase inhibitors (HDIs) induce cell cycle arrest, differentiation, or apoptosis in numerous cancer cell types both in vivo and in vitro. These dramatic effects are the result of a specific reprogramming of gene expression. However, the mechanism by which these agents activate the transcription of some genes, such as p21WAF1, but repress others, such as cyclin D1, is currently unknown. We have been studying the human SRC gene as a model for HDI-mediated transcriptional repression. We found previously that both the tissue-specific and housekeeping SRC promoters were equally repressed by HDIs. Here we show that, despite an overt dissimilarity, both SRC promoters do share similar core promoter elements and transcription is TAF1 dependent. Detailed analysis of the SRC promoters suggested that both core and proximal promoter elements were responsible for HDI-mediated repression. This was confirmed in a series of promoter-swapping experiments with the HDI-inducible, TAF1-independent p21WAF1 promoter. Remarkably, all the Src-p21WAF1 chimeric promoter constructs were not only repressed by HDIs but also dependent on TAF1. Together these experiments suggest that the overall promoter architecture, rather than discrete response elements, is responsible for HDI-mediated repression, and they implicate core promoter elements in particular as potential mediators of this response.
AB - Histone deacetylase inhibitors (HDIs) induce cell cycle arrest, differentiation, or apoptosis in numerous cancer cell types both in vivo and in vitro. These dramatic effects are the result of a specific reprogramming of gene expression. However, the mechanism by which these agents activate the transcription of some genes, such as p21WAF1, but repress others, such as cyclin D1, is currently unknown. We have been studying the human SRC gene as a model for HDI-mediated transcriptional repression. We found previously that both the tissue-specific and housekeeping SRC promoters were equally repressed by HDIs. Here we show that, despite an overt dissimilarity, both SRC promoters do share similar core promoter elements and transcription is TAF1 dependent. Detailed analysis of the SRC promoters suggested that both core and proximal promoter elements were responsible for HDI-mediated repression. This was confirmed in a series of promoter-swapping experiments with the HDI-inducible, TAF1-independent p21WAF1 promoter. Remarkably, all the Src-p21WAF1 chimeric promoter constructs were not only repressed by HDIs but also dependent on TAF1. Together these experiments suggest that the overall promoter architecture, rather than discrete response elements, is responsible for HDI-mediated repression, and they implicate core promoter elements in particular as potential mediators of this response.
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U2 - 10.1128/MCB.24.6.2296-2307.2004
DO - 10.1128/MCB.24.6.2296-2307.2004
M3 - Article
C2 - 14993269
AN - SCOPUS:1542344342
SN - 0270-7306
VL - 24
SP - 2296
EP - 2307
JO - Molecular and cellular biology
JF - Molecular and cellular biology
IS - 6
ER -