The ATP binding cassette (ABC) superfamily of membrane transporters is one of the largest protein classes known, and counts for numerous proteins involved in trafficking of biological molecules across membranes, host-defense mechanism to xenobiotics.
The first known members were P-glycoprotein (P-gp) and multidrug resistant protein (MRP), cause multidrug resistance when transfected into drug-sensitive cells.
In addition, increasing numbers of ABC proteins have recently been identified.
The human ABCG1 (ABC, subfamily G, member 1) gene encodes a member of ABC superfamily that mediates the ATP-dependent translocation of variety of amphiphilic and lipophilic molecules.
ABCG proteins were able to transport substances across cellular membranes and against concentration gradient they require an input of energy, which requires the hydrolysis of ATP, directly or indirectly.
Rat ABCG8 protein is alternatively spliced: A full length isoforms 3 (694-aa), isoforms 2 (671-aa; missing 56-77 aa, and 398-aa); isoforms 1 (672aa, missing 56-77 aa).
Actual expression of various protein isoforms and their physiological relevance is not understood.
ABCG8 may form heterodimers with ABCG5 or be tightly coupled to ABCG5 along a pathway regulating dietary-sterol absorption and excretion.
ABCG8 protein is highly expressed in liver, intestine and colon.
Defects in ABCG8 cause sitosterolemia.
Applications:Suitable for use in ELISA.
Western Blot, though not tested, may potentially be used as an application.
