ABCG8

ABCG8 is a member of the superfamily of ATP-binding cassette (ABC) transporters. ABC proteins transport various molecules across extra- and intra-cellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN

ATP Binding Cassette Subfamily G Member 8

ABCG5 and ABCG8 form an obligate heterodimer that mediates Mg2+- and ATP-dependent sterol transport across the cell membrane. Plays an essential role in the selective transport of the dietary cholesterol in and out of the enterocytes and in the selective sterol excretion by the liver into bile. Required for normal sterol homeostasis. The heterodimer with ABCG5 has ATPase activity.

Bile acid signaling pathway
Cholesterol efflux
Cholesterol homeostasis
Excretion
Intestinal cholesterol absorption
Intracellular receptor signaling pathway
Lipid transport
Negative regulation of intestinal cholesterol absorption
Negative regulation of intestinal phytosterol absorption
Phospholipid transport
Response to drug
Response to muscle activity
Response to nutrient
Sterol transport
Triglyceride homeostasis

Cell membrane; Apical cell membrane

One of the major digestive diseases. Gallstones composed of cholesterol (cholelithiasis) are the common manifestations in western countries. Most people with gallstones, however, remain asymptomatic through their lifetimes.
A form of sitosterolemia, an autosomal recessive metabolic disorder characterized by unregulated intestinal absorption of cholesterol, phytosterols and shellfish sterols, and decreased biliary excretion of dietary sterols into bile. Patients have hypercholesterolemia, very high levels of plant sterols in the plasma, and frequently develop tendon and tuberous xanthomas, accelerated atherosclerosis and premature coronary artery disease.

Cytoplasmic: 1-416 aa
Helical: 417-437 aa
Extracellular: 438-447 aa
Helical: 448-468 aa
Cytoplasmic: 469-497 aa
Helical: 498-518 aa
Extracellular: 519-527 aa
Helical: 528-548 aa
Cytoplasmic: 549-555 aa
Helical: 556-576 aa
Extracellular: 577-639 aa
Helical: 640-660 aa
Cytoplasmic: 661-673 aa

N-glycosylated.