In molecular biology, a GC box is a distinct pattern of nucleotides found in the promoter region of some eukaryotic genes upstream of the TATA box and approximately 110 bases upstream from the transcription initiation site. It has a consensus sequence GGGCGG which is position dependent and orientation independent. The GC elements are bound by transcription factors and have similar functions to enhancers.
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GC box Wikipedia(Text) CC BY-SA