CAAT Box 

 A CAAT box is a cis-acting regulatory element in transcription that contains the sequence 5′-CCAAT-3′ at its core and is bound by one or more different transcription factors. These include but are not limited to C/EBP and various members of the CTF/NF1 family of proteins. Because of the multiplicity of transcription factors that recognize a CAAT box, it is usually not possible to determine the identity of the particular factor that regulates expression of a gene by simple sequence inspection. CAAT boxes are found upstream of a number of genes transcribed by RNA polymerase II and increase the transcriptional rate of the gene above the level that could be achieved by the transcriptional core machinery in the absence of a CAAT box. These cis-acting sequence elements are generally found upstream of the TATA box, but their exact position relative to it is variable, and they may be found in either orientation relative to the direction of transcription from the downstream initiation site.