A short autonomous repression motif is located within the N-terminal domain of CTCF

AbstractThe vertebrate transcription factor CTCF is not only involved in transcriptional activation, insulation and genomic imprinting, but also in transcriptional repression. Sequence motifs mediating these activities have not been identified so far. We have mapped a short repression motif to residues 150–170 within the N-terminal domain of CTCF. This motif is active in HeLa, HEK293 and COS-7 cell lines where it is both sufficient and necessary for silencing either an SV40-, or a CMV-enhancer. It also represses the basal activity of an SV40 core promoter. Since this autonomous repression motif displays no sequence similarity to any other regulatory protein, it represents a yet unknown co-repressor recruiting motif