TY - JOUR
T1 - Chromatin immunoprecipitation (ChIP) on chip experiments uncover a widespread distribution of NF-Y binding CCAAT sites outside of core promoters
AU - Testa, Anna
AU - Donati, Giacomo
AU - Yan, Pearlly
AU - Romani, Francesca
AU - Huang, Tim H.M.
AU - Viganò, M. Alessandra
AU - Mantovani, Roberto
PY - 2005/4/8
Y1 - 2005/4/8
N2 - The CCAAT box is a prototypical promoter element, almost invariably found between -60 and -100 upstream of the major transcription start site. It is bound and activated by the histone fold trimer NF-Y. We performed chromatin immunoprecipitation (ChIP) on chip experiments on two different CpG islands arrays using chromatin from hepatic HepG2 and pre-B cell leukemia NALM-6 cell lines, with different protocols of probe preparation and labeling. We analyzed and classified 239 known or predicted targets; we validated several by conventional ChIPs with anti-YB and anti-YC antibodies, in vitro EMSAs, and ChIP scanning. The importance of NF-Y binding for gene expression was verified by the use of a dominant negative NF-YA mutant. All but four genes are new NF-Y targets, falling into different functional categories. This analysis reinforces the notion that NF-Y is an important regulator of cell growth, and novel unexpected findings emerged from this unbiased approach. (i) A remarkable proportion of NF-Y targets, 40%, are complex transcriptional units composed of divergent, convergent, and tandem promoters. (ii) 40-50% of NF-Y sites are not in core promoters but are in introns or at distant 3′ or 5′ locations. The abundance of "unorthodox" CCAAT positions highlights an unexpected complexity of the NF-Y-mediated transcriptional network.
AB - The CCAAT box is a prototypical promoter element, almost invariably found between -60 and -100 upstream of the major transcription start site. It is bound and activated by the histone fold trimer NF-Y. We performed chromatin immunoprecipitation (ChIP) on chip experiments on two different CpG islands arrays using chromatin from hepatic HepG2 and pre-B cell leukemia NALM-6 cell lines, with different protocols of probe preparation and labeling. We analyzed and classified 239 known or predicted targets; we validated several by conventional ChIPs with anti-YB and anti-YC antibodies, in vitro EMSAs, and ChIP scanning. The importance of NF-Y binding for gene expression was verified by the use of a dominant negative NF-YA mutant. All but four genes are new NF-Y targets, falling into different functional categories. This analysis reinforces the notion that NF-Y is an important regulator of cell growth, and novel unexpected findings emerged from this unbiased approach. (i) A remarkable proportion of NF-Y targets, 40%, are complex transcriptional units composed of divergent, convergent, and tandem promoters. (ii) 40-50% of NF-Y sites are not in core promoters but are in introns or at distant 3′ or 5′ locations. The abundance of "unorthodox" CCAAT positions highlights an unexpected complexity of the NF-Y-mediated transcriptional network.
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U2 - 10.1074/jbc.M414039200
DO - 10.1074/jbc.M414039200
M3 - Article
C2 - 15647281
AN - SCOPUS:17144395919
SN - 0021-9258
VL - 280
SP - 13606
EP - 13615
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 14
ER -