E-box

CTRR and Ebox

File:Nrn2215-f4.jpg

Nrn2215-f4

E-box

The E-box (enhancer box) is a specific DNA sequence recognized by certain transcription factors. It plays a crucial role in the regulation of gene expression in eukaryotic cells. The consensus sequence for the E-box is CANNTG, where "N" can be any nucleotide.

Structure and Function

The E-box is typically found in the promoter or enhancer regions of genes. It serves as a binding site for basic helix-loop-helix (bHLH) transcription factors, such as Myc, Max, and MyoD. These transcription factors bind to the E-box to regulate the transcription of target genes, influencing various cellular processes including cell cycle, differentiation, and apoptosis.

Role in Gene Regulation

E-boxes are critical in the regulation of genes involved in development, metabolism, and circadian rhythms. For example, the CLOCK and BMAL1 proteins, which are key components of the circadian clock, bind to E-boxes to regulate the expression of genes that control daily physiological rhythms.

Clinical Significance

Mutations or dysregulation of E-box binding proteins can lead to various diseases, including cancer. For instance, the overexpression of the Myc protein, which binds to E-boxes, is associated with many types of cancer due to its role in promoting cell proliferation.

Related Transcription Factors

• Myc
• Max
• MyoD
• CLOCK
• BMAL1

See Also

• Transcription factor
• Gene expression
• Promoter (genetics)
• Enhancer (genetics)
• Basic helix-loop-helix