Role of NF-Y in in vivo regulation of the gamma-globin gene

The duplicated CCAAT box is required for gamma gene expression. We report h ere that the transcriptional factor NF-Y is recruited to the duplicated CCA AT box in vivo. A mutation of the duplicated CCAAT box that severely disrup ts the NF-Y binding also reduces the accessibility level of the gamma gene promoter, affects the assembly of basal transcriptional machinery, and incr eases the recruitment of GATA-1 to the locus central region (LCR) and the p roximal promoter and the recruitment of transcription cofactor CBP/p300 to the LCR. These findings suggest that recruitment of NF-Y to the duplicated CCAAT box plays a role in the chromatin opening of the gamma gene promoter as well as in the communication between the gamma gene promoter and the LCR .