Family transporters

Organic Anion Transporters (OATs SLC22A) Multispecific, organic anion transporters/exchangers Oatl and Oat3 are Indirectly coupled to Na 

Substrates NSAIDS, fluoroquinolones, -lactam antibiotics, nucleoside phosphonates (Oatl), 

PAH (Oatl and Oat3), AZT, prostaglandins, statins, cimetidine (Oat3), MTX, Ihyroxine, GSH, glucuronlde and sulfate conjugates 

Organic Anion Transporting Polypeptides (OATPs SLC21) Multispecific, organic anion 

Substrates MTX, thyroxines, digoxin (Oatp2), bile salts, peptides, eicosanoids, statins, GSH, glucuronide and sulfate conjugates of hormones 

---

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. 

Scheepers A, Joost HG, Schurmann A (2004) The glucose transporter families SGLT and GLUT molecular basis of normal and aberrant function. JPEN J Parenter Enteral Nub 28 364-371... 

Kanai Y, Hediger MA (2004) The glutamate/neutral amino acid transporter family SLC1 molecular, physiological and pharmacological aspects. Pfliigers Arch 447 469-479... 

Chen NH, Reith ME, Quick MW (2004) Synaptic uptake and beyond the sodium- and chloride-dependent neurotransmitter transporter family SLC6. Pfliigers Arch 447 519-531... 

Aymerich I, Duflot S, Fernandez-Veledo S, Guillen-Gomez E, Huber-Ruano I, Casado FJ, et al. The concentrative nucleoside transporter family (SLC28) new roles beyond salvage Biochem Soc Trans 2005 33 216-9. 

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... 

Aligned sequences of 16 members of the sugar transporter family. Residues which are identical in 5=50% of the 16 sugar-transporter sequences (excluding the quinate transporter (qa-y), the citrate transporter (CIT), the tetracycline transporter (pBR322) and lac permease (LacY)) are highlighted, and recorded below the sequences as CONSERVED . The locations of predicted membrane-spanning helices are indicated by horizontal bars. The sequences were taken from the references cited in the text. 

The lactose transporter (lac permease) of E. coli is without doubt the most intensively studied and best understood of the bacterial proton-linked sugar transporters. Since its sequence was reported in 1980 [233] prodigious efforts have been made to elucidate its molecular mechanism by site-directed mutagenesis and other means. These studies have recently been reviewed elsewhere [234,235] and so will not be discussed in detail here. The important question for the present Chapter is whether the protein is related to the sugar-transporter family and so has lessons to teach us about their mechanisms. The permease is a 417-residue protein, and, like the other... 

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). 

Following the release of dopamine, the primary mode of removal from the synapse is reuptake into the presynaptic neuron via the dopamine transporter (DAT). DAT is dependent upon the energy created by the Na+/K+ pump and is a member of the Na+/Cl -dependent plasma membrane transporter family, as are the norepinephrine and 7-aminobutyric acid (GABA) transporters. Imaging studies utilizing compounds with highly specific affinity for DAT... 

B. Sjostrom et al. Correlation of gene expression of ten drug efflux proteins of the atp-binding cassette transporter family in normal human jejunum and in human intestinal epithelial caco-2 cell monolayers, /. Pharmacol. Exp. Ther. 2001, 299, 164-170... 

In cell lines, the organic anion transporters (OAT and OATP) have been identified and cloned into cells of kidney origin such as LLC-PK1, MDCK, HK-2, and Caco-2 [129]. The most well-known uptake transporters, which transport the substrate over the membrane into the organism are the amino acid- [35, 42, 139] and oligopeptide-carriers (PepTl and PepT2) [139-142]. These two transporter families are abundantly expressed in the small intestine of most animals, and can therefore be involved in the absorption process of pharmaceutical drugs. The PepTl is expressed in the cell lines Caco-2 and HT-29 [140-142]. 

Wu, X., et al. cDNA sequence, transport function, and genomic organization of human OCTN2, a new member of the organic cation transporter family. Biochem. Biophys. Res. Commun. 1998, 246, 589-595. 

Tamai, I., et al. Molecular and functional characterization of organic cation/camitine transporter family in mice. J. Biol. Chem. 2000, 275, 40064-40072. 

Phay, J. E., H. B. Hussain, and J. F. Moley. Cloning and expression analysis of a novel member of the facilitative glucose transporter family, SLC2A9 (GLUT9). Genomics 2000, 66, 217-220. 

Dutta, B., et al. Cloning of the human thiamine transporter, a member of the folate transporter family. J. Biol. Chem. 1999, 274, 31925-31929. 

Price, N. T., V. N. Jackson, and A. P. Halestrap. Cloning and sequencing of four new mammalian monocarb-oxylate transporter (MCT) homologues confirms the existence of a transporter family with an ancient past. Biochem. 

OATP-C, a liver-specific member of this transporter family, was cloned by number of groups [17, 30-32] and often referred by aliases such as liver-specific transporter 1 (LST-1) and OATP2. Immunohistochemical analysis proved OATP-C expression on the basolateral membrane of hepatocytes [32]. As with OATP-A, OATP-C... 

Novel Organic Cation Transporter Family (OCTN) 1193... 

---