Liver X Receptor Alpha (LXRa)

Retinoic acid mediates tissue-specific expression of target genes through its binding to nuclear hormone receptors. To activate transcription, these receptors bind specific sites, called hormone response elements, within the target gene"""s regulatory region. Willy et al. identified a cDNA encoding NR1H3, or LXRA, an orphan member of the nuclear receptor superfamily. The predicted 447-amino acid LXRA protein contains a DNA-binding domain and a putative ligand-binding domain; the amino acid sequences of these domains are 77% identical to those of NR1H2 .Willy et al. identified a distinct retinoid response element for LXRA/RXRA heterodimers, termed the LXR-responsive element, that consists of 2 degenerate copies of the consensus hexad sequence spaced by 4 nucleotides.