GC+box

=GC box=

A **GC box** is a conserved nucleotide sequence in eukaryotes with the consensus sequence 5' GGGCGG 3'.

It acts in a similar fashion to an enhancer sequence, binding proteins called Sp1s which further stabilise the preinitiation complex at the promoter of a gene, and thereby increase the rate of transcription of that gene. GC boxes are a type of //promoter-proximal element//, like the nearby CAAT region. GC boxes are generally located about 110 base pairs upstream of the transcription initiation site.