Biochem/physiol Actions

Liver X receptors (LXRs) are nuclear receptors that regulate the metabolism of cholesterol and bile acids. There are two subtypes of LXRs, LXR α and LXR β. LXR β is preferentially expressed in liver, small intestine, kidney and spleen. In contrast, LXR α expression is ubiquitous. The genomic structure and the promoter regions of the two LXR genes contain specific regulatory sites, which suggest that LXRs may have physiological roles in the immune system. Like other nuclear receptors, LXRs heterodimerize with retinoid X receptor (RXR) for function. LXRs are activated by naturally occurring oxysterols and regulate the expression of target genes, including ATP binding cassette transporter 1 (ABC1), ATP binding cassette transporter 8 (ABC8) and cholesterol ester transfer protein (CETP). LXR β expressed in livers of LXR α knockout mice does not compensate for the loss of LXR α. In addition, LXR β, but not LXR α, is also able to activate transcription of a reporter gene, which contains a specific direct repeat separated by 1 bp (DR1) element in the promoter, suggesting that LXR β may have different biological functions.

Physical form

Clear and colorless frozen liquid solution

Preparation Note

Use a manual defrost freezer and avoid repeated freeze-thaw cycles. While working, please keep sample on ice.