ABC-transporter family

The breast cancer resistance protein (BCRP) belongs to the G-branch of the ABC-transporter family (ABCG2). In contrast to most other ABC-proteins, BCRP consists of only one transmembrane domain (TDM) with one nucleotide binding fold (NBF) at its C-terminus. Because of this structural characteristic BCRP as well as other ABC-transporters with only one TMD are termed half transporters. To achieve functional activity these transporters have to form hetero- or homodimers. BCRP is involved in the multidrug resistance of certain tumors and transports endogenous compounds like cholesterol and steroid hormones. 

Mahd, B., Masclaux, C., Rauscher, L., Enard, C., and Expert, D. 1995. Differential expression of two siderophore-dependent-iron acquisition pathways in Erwinia cf santhemi 3937 characterization of a novel ferrisiderophore permease of the ABC transporter family. Mol. Microbiol. 18 33-43... 

Intracellular transport and efflux from cells of lipophilic molecules can be mediated by several members of the ATP-binding cassette (ABC) transporters family, some of which have been identified in the brain, including the retina (Kim et al., 2008 Sarkadi et al., 2006). 

Adrenoleukodystrophy X-linked Peroxisomal membrane protein in the ABC transporter family Decreased peroxidation of saturated, very-long-chain fatty acids, causing their accumulation in brain, adrenals and other tissues variable phenotypes with regard to hypomyelination see text 1,26, Ch. 40... 

In addition, both ATM1 and Ervl, which are required for the maturation of extra-mitochondrial (cytosolic) proteins and that are part of the mt export machinery, have been identified in the C. parvum genome (reviewed in Barbera et al. 2006). The former is an IM protein of the ABC transporter family that faces the mt matrix (Decottignies and Goffeau 1997), and the second is an intermembrane sulhydryl oxidase whose function in cytosolic FeS protein biosynthesis is still unknown (reviewed in Barbera et al. 2006). When combined with glutathione, which may help stabilize proteins being exported from the mitochondrion into the cytosol (reviewed in Tachezy and Dolezal... 

ATP-dependent ABC transporter family. However, it is atypical because it also contains a regulated chloride channel) In secretory epithelia of intestines, pancreas, lungs, sweat glands, and kidneys Cl enters epithelial cells through their basolateral surfaces using an Na+ + K+ + 2 Cl cotransporter and exits the cells through their apical surfaces using the CFTR channel. Absorptive epithelia also contain both the cotransporter and the CFTR channel, but Cl flows into the cells from the exterior surface, and the distribution of the cotransporter and CFTR between basolateral and apical surfaces is opposite to that in secretory cells.1... 

Highly populated protein domain families of H. pylori include (1) the cellular component Helicobacter outer membrane protein family (2) the sell family, which is associated with P-lactamase activity (3) members of the CagA and VacA protein families, which are secreted into host cells and are involved in pathogenesis (4) the ABC transporter family, which is associated with ATP-dependent transport of molecules across the membrane (5) the DNA methyltransferase protein domain family (6) the radical SAM (S-adenosylmethionine) family associated with various metabolic functions of pathogens and (7) the response regulator receiver domain family, which is involved in receiving the signal from the sensor domain in bacterial two-component systems. 

Efflux pumps from the ABC transporter family are expressed multidrug resistance protein MDR1 (= Pgp), ABCG2 (= BCRP), MRP1 and MRP2 (Cordon-Cardo et al. 1990 Hunter et al. 1993 and others). 

Organic Solute Transporter Organic Anion Transporting ABC Transporter Family ... 

The structure of P-glycoprotein has not been determined. However, X-ray crystallographic structures have been determined for bacterial members of the ABC transporter family the MsbA lipid A "flippases" from E. coli (72) and Vibrio cholera (73) and the cobal-amin uptake transporter BtuCD protein of E. coli (74). These structures are consistent with the overall picture of P-glycoprotein function described here. 

Transport mechanisms fortubular secretion of organic anions Tubular transport of organic cations ABC transporter family... 

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