HDL

SR-B1 belongs to the CD36 scavenger receptor family and serves as a receptor for several ligands including phospholipids, cholesterol ester, lipoproteins, phosphatidylserine, and caveolae localized HDL. It is expressed in endothelial cells, macrophages, and dendritic cells. It facilitates the flux of both free and esterified cholesterol between the cell surface and extracellular donors and acceptors (HDL and to a lesser extent, apoB-containing lipoproteins and modified lipoproteins).

SREBP1 (sterol-regulatory-element-binding protein 2) is a basic-helix-loop-helix-leucine zipper (bHLH-ZIP) transcription factor. It regulates sterol and cholesterol homeostasis by controlling enzymes involved in cholesterol synthesis and uptake, e.g. HMG-CoA. The SREBP1 antibody was used in fundamental studies to dissect SREBP1 domains and downstream signaling (1).

Sterol-regulatory-element-binding protein 2 (SREBP2) is a transcription factor that regulates cholesterol homeostasis by controlling enzymes involved in cholesterol synthesis and uptake, e.g. HMG-CoA.

LXR Alpha, also known as Liver X receptor Alpha is a 50KDa protein that belongs to the nuclear hormone receptor family located in the nucleus. It is specifically expressed in the liver, kidney and intestine; however it has also been found in the spleen, macrophages and the adrenals. All of these tissues play an important role in lipid metabolism. The primary role of LXR Alpha is to maintain cholesterol homeostasis in macrophages by regulating the genes involved in this.

Scavenger Receptor Class B Membrane 1, also known as SR-BI plays an important role in lipid metabolism. Its main function is to mediate transfer of cholesterol between the cell surface and high density lipoprotein (HDL). HDL acts as an extracellular donor and acceptor of free and esterified Cholesterol. SR-BI also acts as a receptor for other ligands including lipoproteins, apoptotic cells and phospholipids.