Retinoic acid response element (RARE) (RARE)

Retinoic acid response elements (RAREs) are specific cis-regulatory DNA sequences located within the promoter or enhancer regions of genes that are transcriptionally regulated by retinoic acid (RA) (Cunningham & Duester, 2015). These motifs typically consist of two direct repeats of the consensus hexameric sequence 5'-PuGGTCA-3', most commonly separated by five nucleotides (DR5), though spacers of one (DR1) or two (DR2) nucleotides also occur (Chambon, 1996). RAREs serve as the primary binding sites for heterodimers of the retinoic acid receptor (RAR) and the retinoid X receptor (RXR). In the absence of ligand, the RAR/RXR complex binds to the RARE and recruits corepressor proteins and histone deacetylases to maintain a repressed chromatin state. Upon binding of a retinoid ligand, such as all-trans retinoic acid (ATRA), the receptors undergo a conformational change that triggers the release of corepressors and the recruitment of coactivators, leading to the induction of gene expression (Siddikuzzaman et al., 2011). This regulatory mechanism is essential for controlling cell differentiation, embryonic development, and tissue homeostasis. Dysregulation of RARE-mediated signaling is a hallmark of certain diseases, most notably acute promyelocytic leukemia (APL), where the PML-RARalpha fusion protein interferes with normal RARE binding and gene activation (Gudas & Wagner, 2011). Therapeutic agents like tretinoin and bexarotene exert their effects by modulating the activity of receptors bound to these DNA motifs.

Other names

RARERetinoic acid response elementDR5DR2DR1Retinoid response element

Ligand-induced recruitment of retinoic acid receptors (RAR/RXR) to DNA motifs to modulate transcription of target genes.