ABCC6

The protein encoded by this gene 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, GCN20, White). The encoded protein, a member of the MRP subfamily, is involved in multi-drug resistance. Mutations in this gene cause pseudoxanthoma elasticum. Alternatively spliced transcript variants that encode different proteins have been described for this gene. [provided by RefSeq, Jul 2008]

Full Name

ATP Binding Cassette Subfamily C Member 6

Function

Isoform 1: ATP-dependent transporter of the ATP-binding cassette (ABC) family that actively extrudes physiological compounds, and xenobiotics from cells. Mediates ATP-dependent transport of glutathione conjugates such as leukotriene-c4 (LTC4) and N-ethylmaleimide S-glutathione (NEM-GS) (in vitro), and an anionic cyclopentapeptide endothelin antagonist, BQ-123. Does not appear to actively transport drugs outside the cell. Confers low levels of cellular resistance to etoposide, teniposide, anthracyclines and cisplatin.Mediates the release of nucleoside triphosphates, predominantly ATP, into the circulation, where it is rapidly converted into AMP and the mineralization inhibitor inorganic pyrophosphate (PPi) by the ecto-enzyme ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1), therefore playing a role in PPi homeostasis.
Isoform 2: Inhibits TNF-alpha-mediated apoptosis through blocking one or more caspases.

Biological Process

ATP transport
Cellular phosphate ion homeostasis
Drug transmembrane transport
Leukotriene transport
Response to drug
Transmembrane transport
Visual perception

Cellular Location

Isoform 1: Basolateral cell membrane
Isoform 2: Endoplasmic reticulum membrane

Involvement in disease

A multisystem disorder characterized by accumulation of mineralized and fragmented elastic fibers in the skin, vascular walls, and Burch membrane in the eye. Clinically, patients exhibit characteristic lesions of the posterior segment of the eye including peau d'orange, angioid streaks, and choroidal neovascularizations, of the skin including soft, ivory colored papules in a reticular pattern that predominantly affect the neck and large flexor surfaces, and of the cardiovascular system with peripheral and coronary arterial occlusive disease as well as gastrointestinal bleedings.
A severe autosomal recessive disorder characterized by calcification of the internal elastic lamina of muscular arteries and stenosis due to myointimal proliferation. The disorder is often fatal within the first 6 months of life because of myocardial ischemia resulting in refractory heart failure.

Topology

Extracellular: 1-31 aa
Helical: 32-52 aa
Cytoplasmic: 53-72 aa
Helical: 73-93 aa
Extracellular: 94-98 aa
Helical: 99-119 aa
Cytoplasmic: 120-131 aa
Helical: 132-149 aa
Extracellular: 150-167 aa
Helical: 168-188 aa
Cytoplasmic: 189-302 aa
Helical: 303-323 aa
Extracellular: 324-349 aa
Helical: 350-370 aa
Cytoplasmic: 371-426 aa
Helical: 427-447 aa
Extracellular: 448-450 aa
Helical: 451-471 aa
Cytoplasmic: 472-533 aa
Helical: 534-554 aa
Extracellular: 555-575 aa
Helical: 576-596 aa
Cytoplasmic: 597-939 aa
Helical: 940-960 aa
Extracellular: 961-997 aa
Helical: 998-1018 aa
Cytoplasmic: 1019-1061 aa
Helical: 1062-1082 aa
Extracellular: 1083 aa
Helical: 1084-1104 aa
Cytoplasmic: 1105-1175 aa
Helical: 1176-1196 aa
Extracellular: 1197-1198 aa
Helical: 1199-1219 aa
Cytoplasmic: 1220-1503 aa

PTM

Glycosylated.