Transcription factor cCP2 controls gene expression in chicken embryonic stem cells
Journal - Nucleic Acids Research
Received January 9, 2004; Revised and Accepted March 24, 2004cENS-1/cERNI genes have been shown to be expressed very earlyduring chicken embryonic development and as well as in pluripotentchicken embryonic stem (CES) cells. We have previously identifieda promoter region, which is specifically active in CES cellscompared to differentiated cells. In order to understand themolecular mechanisms which regulate the cENS-1/cERNI promoter,we analyzed the cis-acting elements of this promoter in CESand differentiated cells. We identified a short sequence, namedthe B region, 5'-CAAG TCCAGG CAAG-3', that exhibits a strongenhancer activity in CES and differentiated cells. Mutationof the B region in the whole cENS-1 promoter strongly decreasesthe promoter activity in CES cells, suggesting that this regionis essential for activating the promoter. The B region is similarto the previously described response element for the transcriptionfactor CP2 and we show by supershift experiments that a proteincomplex containing CP2 is bound to this B response element.All these results identify a nuclear factor belonging to theCP2 transcription factor family that is crucial for the activationof the cENS-1/cERNI promoter. The pattern of expression of cCP2in early chicken embryo before gastrulation is very similarto that of cENS-1/cERNI which strongly suggests that cCP2 alsoplays an essential role in gene expression early in embryonicdevelopment.