The ATP-binding cassette transporters are a transport system superfamily that is one of the largest and possibly one of the oldest gene families. It is represented in all extant phyla, from prokaryotes to humans.
An ATP-binding motif is a 250-residue sequence within an ATP-binding protein’s primary structure. The binding motif is associated with a protein’s structure and/or function. ATP is a molecule of energy, and can be a coenzyme, involved in a number of biological reactions. ATP is proficient at interacting with other molecules through a binding site. The ATP binding site is the environment in which ATP catalytically actives the enzyme and, as a result, is hydrolyzed to ADP. The binding of ATP causes a conformational change to the enzyme it is interacting with.
ABCG5 and ABCG8 genes encode for two proteins sterolin-1 and -2, respectively. Sterolin-1 and –2 are two ‘half’ adenosine triphosphate binding (ATP) cassette (ABC) transporters which found to be indispensable for the regulation of sterol absorption and excretion. Mutations in either genes result in a lipid disorder, sitosterolemia.
Translocase is a general term for a protein that assists in moving another molecule, usually across a cell membrane. These enzymes catalyze the movement of ions or molecules across membranes or their separation within membranes. The reaction is designated as a transfer from “side 1” to “side 2” because the designations “in” and “out”, which had previously been used, can be ambiguous. Translocases are the most common secretion system in Gram positive bacteria.
ATP-binding cassette transporter ABCA1, also known as the cholesterol efflux regulatory protein (CERP) is a protein which in humans is encoded by the ABCA1 gene. This transporter is a major regulator of cellular cholesterol and phospholipid homeostasis.
Multidrug resistance-associated protein 1 (MRP1) is a protein that in humans is encoded by the ABCC1 gene.
ABC transporter transmembrane domain is the main transmembrane structural unit of ATP-binding cassette transporter proteins, consisting of six alpha helixes that traverse the plasma membrane. Many members of the ABC transporter family have two such regions.
ATP-binding cassette, sub-family A (ABC1), member 4, also known as ABCA4 or ABCR, is a protein which in humans is encoded by the ABCA4 gene.
ATP-binding cassette sub-family G member 1 is a protein that in humans is encoded by the ABCG1 gene. It is a homolog of the well-known Drosophila gene white.
ATP-binding cassette sub-family G member 8 is a protein that in humans is encoded by the ABCG8 gene.
ATP-binding cassette sub-family A member 2 is a protein that in humans is encoded by the ABCA2 gene.
ATP-binding cassette sub-family B member 9 is a protein that in humans is encoded by the ABCB9 gene.
ATP-binding cassette sub-family A member 7 is a protein that in humans is encoded by the ABCA7 gene.
ATP-binding cassette sub-family A member 3 is a protein that in humans is encoded by the ABCA3 gene.
ATP-binding cassette sub-family D member 4 is a protein that in humans is encoded by the ABCD4 gene.
ATP-binding cassette sub-family G member 4 is a protein that in humans is encoded by the ABCG4 gene.
ATP-binding cassette sub-family A member 8 is a protein that in humans is encoded by the ABCA8 gene.
Multidrug resistance-associated protein 9 is a protein that in humans is encoded by the ABCC12 gene.
The Walker A and Walker B motifs are protein sequence motifs, known to have highly conserved three-dimensional structures. These were first reported in ATP-binding proteins by Walker and co-workers in 1982.
ATP-binding cassette, sub-family A (ABC1), member 5 is a protein that in humans is encoded by the ABCA5 gene.
