ABCB1 p.Phe728Cys
| Predicted by SNAP2: | A: D (66%), C: N (53%), D: D (85%), E: D (80%), G: D (80%), H: D (80%), I: D (66%), K: D (85%), L: D (66%), M: D (53%), N: D (63%), P: D (85%), Q: D (66%), R: D (85%), S: D (71%), T: D (71%), V: D (66%), W: D (66%), Y: N (66%), |
| Predicted by PROVEAN: | A: D, C: D, D: D, E: D, G: D, H: D, I: D, K: D, L: D, M: D, N: D, P: D, Q: D, R: D, S: D, T: D, V: D, W: D, Y: N, |
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[hide] Transmembrane segment 7 of human P-glycoprotein fo... Biochem J. 2006 Oct 15;399(2):351-9. Loo TW, Bartlett MC, Clarke DM
Transmembrane segment 7 of human P-glycoprotein forms part of the drug-binding pocket.
Biochem J. 2006 Oct 15;399(2):351-9., 2006-10-15 [PMID:16813563]
Abstract [show]
P-gp (P-glycoprotein; ABCB1) protects us by transporting a broad range of structurally unrelated compounds out of the cell. Identifying the regions of P-gp that make up the drug-binding pocket is important for understanding the mechanism of transport. The common drug-binding pocket is at the interface between the transmembrane domains of the two homologous halves of P-gp. It has been shown in a previous study [Loo, Bartlett and Clarke (2006) Biochem. J. 396, 537-545] that the first transmembrane segment (TM1) contributed to the drug-binding pocket. In the present study, we used cysteine-scanning mutagenesis, reaction with an MTS (methanethiosulfonate) thiol-reactive analogue of verapamil (termed MTS-verapamil) and cross-linking analysis to test whether the equivalent transmembrane segment (TM7) in the C-terminal-half of P-gp also contributed to drug binding. Mutation of Phe728 to cysteine caused a 4-fold decrease in apparent affinity for the drug substrate verapamil. Mutant F728C also showed elevated ATPase activity (11.5-fold higher than untreated controls) after covalent modification with MTS-verapamil. The activity returned to basal levels after treatment with dithiothreitol. The substrates, verapamil and cyclosporin A, protected the mutant from labelling with MTS-verapamil. Mutant F728C could be cross-linked with a homobifunctional thiol-reactive cross-linker to cysteines I306C(TM5) and F343C(TM6) that are predicted to line the drug-binding pocket. Disulfide cross-linking was inhibited by some drug substrates such as Rhodamine B, calcein acetoxymethyl ester, cyclosporin, verapamil and vinblastine or by vanadate trapping of nucleotides. These results indicate that TM7 forms part of the drug-binding pocket of P-gp.
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None has been submitted yet.
No. Sentence Comment
5 Mutation of Phe728 to cysteine caused a 4-fold decrease in apparent affinity for the drug substrate verapamil.
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ABCB1 p.Phe728Cys 16813563:5:12
status: NEW6 Mutant F728C also showed elevated ATPase activity (11.5-fold higher than untreated controls) after covalent modification with MTS-verapamil.
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ABCB1 p.Phe728Cys 16813563:6:7
status: NEW9 Mutant F728C could be cross-linked with a homobifunctional thiol-reactive cross-linker to cysteines I306C(TM5) and F343C(TM6) that are predicted to line the drug-binding pocket.
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ABCB1 p.Phe728Cys 16813563:9:7
status: NEW74 Mutant Verapamil S50 (µM) Vinblastine S50 (µM) Colchicine S50 (µM) F711C 9.8 + - 1.1 2.3 + - 0.2 410 + - 20 V712C 10.0 + - 0.8 1.9 + - 0.2 320 + - 40 V713C 9.9 + - 1.3 1.8 + - 0.2 340 + - 40 G714C 14.1 + - 2.1 1.9 + - 0.3 410 + - 30 V715C 9.8 + - 1.3 1.8 + - 0.3 330 + - 40 F716C 10.1 + - 1.0 2.1 + - 0.1 340 + - 30 C717C 10.0 + - 1.5 2.3 + - 0.3 390 + - 20 A718C 10.5 + - 1.3 2.0 + - 0.1 330 + - 30 I719C 10.5 + - 1.5 1.9 + - 0.2 370 + - 30 I720C 12.4 + - 0.7 2.4 + - 0.2 390 + - 10 N721C 13.0 + - 1.2 1.7 + - 0.2 380 + - 40 G722C ND ND ND G723C 11.1 + - 0.4 2.0 + - 0.3 410 + - 20 L724C 12.0 + - 1.5 2.4 + - 0.3 340 + - 30 Q725C 11.7 + - 1.1 2.0 + - 0.1 390 + - 20 P726C 11.9 + - 1.0 1.9 + - 0.2 450 + - 30 A727C 21.2 + - 3.1 1.9 + - 0.2 480 + - 40 F728C 48.7 + - 2.2 2.7 + - 0.3 830 + - 90 A729C 34.3 + - 3.0 2.3 + - 0.2 760 + - 80 I730C 12.0 + - 1.1 2.0 + - 0.1 420 + - 30 I731C 13.5 + - 1.9 1.9 + - 0.2 410 + - 30 Cys-less 11.6 + - 1.3 2.1 + - 0.3 400 + - 40 into the endoplasmic reticulum during synthesis of the protein.
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ABCB1 p.Phe728Cys 16813563:74:766
status: NEW85 Table 1 shows that two mutants, F728C and A729C, showed about 4.2and 3-fold decreases respectively, in the apparent affinity for verapamil when compared with Cys-less P-gp.
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ABCB1 p.Phe728Cys 16813563:85:32
status: NEW97 Samples of the isolated P-gp were mixed with lipid and assayed for ATPase activity and compared with untreated P-gp. All of the mutants, except Q725C, P726C, F728C and A729C, were unaffected by treatment with MTS-verapamil (Figure 2A).
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ABCB1 p.Phe728Cys 16813563:97:158
status: NEW99 By contrast, the ATPase activity of mutants Q725C, F728C and A729C increased 2.6-, 4.7and 4.5-fold respectively, compared with untreated mutant P-gp.
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ABCB1 p.Phe728Cys 16813563:99:51
status: NEW100 Although mutants Q725C, F728C and A729C showed increased ATPase activity after treatment with MTS-verapamil, the activities were less than 50% of the verapamil-stimulated ATPase activity of Cys-less P-gp (maximum 11.1-fold stimulation; Figure 2B).
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ABCB1 p.Phe728Cys 16813563:100:24
status: NEW101 We have shown previously that mutants Q725C, F728C and A729C were stimulated more than 10-fold with verapamil [37].
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ABCB1 p.Phe728Cys 16813563:101:45
status: NEW103 Therefore it was possible that reaction of MTS-verapamil with mutants Q725C, F728C and A729C was incomplete or that they were completely modified but the bound verapamil was in a sub-optimal conformation for activation of ATPase activity.
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ABCB1 p.Phe728Cys 16813563:103:77
status: NEW104 To distinguish between these two possibilities, mutants Q725C, F728C and A729C (activated by 0.3 mM MTS-verapamil) were treated with or without 3 mM MTS-verapamil.
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ABCB1 p.Phe728Cys 16813563:104:63
status: NEW109 In contrast, labelling of mutants Q725C or F728C with 3 mM MTS-verapamil increased their ATPase activities further Figure 2 Effect of MTS-verapamil on basal ATPase activity of TM7 cysteine mutants (A) His-tagged Cys-less or mutants F711C/I731C P-gps were expressed in HEK-293 cells and solubilized with n-dodecyl-β-D-maltoside. Insoluble material was removed by centrifugation and the supernatants were treated with or without 0.3 mM MTS-verapamil.
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ABCB1 p.Phe728Cys 16813563:109:43
status: NEW112 (B) Cys-less, Q725C, F728C and A729C P-gp mutants were treated with or without 3 mM MTS-verapamil and His-tagged P-gp isolated by nickel-chelate chromatography. Equivalent amounts of P-gp were mixed with lipid and ATPase activity determined in the presence (+) or absence (-) of 1 mM verapamil (Ver).
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ABCB1 p.Phe728Cys 16813563:112:21
status: NEW117 Therefore mutants Q725C and F728C were chosen for further investigation because their labelling with MTS-verapamil appeared to mimic the interaction of P-gp with unmodified verapamil.
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ABCB1 p.Phe728Cys 16813563:117:28
status: NEW118 We then tested whether drug substrates could protect mutants Q725C and F728C from being labelled by MTS-verapamil.
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ABCB1 p.Phe728Cys 16813563:118:71
status: NEW119 HEK-293 cells expressing mutants Q725C or F728C were solubilized with n-dodecyl-β-D-maltoside and then treated with or without saturating levels of verapamil (3 mM), cyclosporin A (0.2 mM), colchicine (10 mM) or trans-(E)-flupentixol (0.6 mM).
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ABCB1 p.Phe728Cys 16813563:119:42
status: NEW123 Figure 3 shows that the substrates verapamil and cyclosporin A protected mutant F728C, but not mutant Q725C, from labelling with MTS-verapamil.
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ABCB1 p.Phe728Cys 16813563:123:80
status: NEW126 Therefore mutant F728C was selected for further analysis because some drug substrates protected it from labelling by MTS-verapamil.
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ABCB1 p.Phe728Cys 16813563:126:17
status: NEW127 The reaction of mutant F728C with higher concentrations of MTS-verapamil showed that maximum stimulation (11.5-fold) occurred in the presence of 3-10 mM MTS-verapamil (see Figure 1 of supplementary data at http://www.BiochemJ.org/ bj/399/bj3990351add.htm).
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ABCB1 p.Phe728Cys 16813563:127:23
status: NEW129 We then confirmed that activation of mutant F728C was indeed due to covalent attachment of MTS-verapamil to Cys728 .
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ABCB1 p.Phe728Cys 16813563:129:44
status: NEW130 HEK-293 cells expressing mutant F728C were treated with 3 mM MTS-verapamil for 10 min at 20◦ C and His-tagged P-gp isolated by nickel-chelate chromatography.
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ABCB1 p.Phe728Cys 16813563:130:32
status: NEW132 Exposure of the MTS-verapamil labelled F728C mutant to DTT caused a 75% decrease in ATPase activity (see Figure 3 Inhibition of MTS-verapamil labelling of mutants Q725C and F728C by substrates HEK-293 cells expressing mutants Q725C or F728C were solubilized with n-dodecyl- β-D-maltoside. Insoluble material was removed by centrifugation.
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ABCB1 p.Phe728Cys 16813563:132:39
status: NEWX
ABCB1 p.Phe728Cys 16813563:132:173
status: NEWX
ABCB1 p.Phe728Cys 16813563:132:235
status: NEW138 We then tested whether other drug substrates could stimulate further the ATPase activity of MTS-verapamil-treated mutant F728C.
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ABCB1 p.Phe728Cys 16813563:138:121
status: NEW140 Mutant F728C was treated with or without Figure 4 Effect of drug substrates and inhibitors on the ATPase activity of mutants F728C and Q725C before and after labelling with MTS-verapamil HEK-293 cells expressing His-tagged mutants F728C or Q725C were solubilized with n-dodecyl-β-D-maltoside and then incubated in the absence (A and C) or presence (B and D) of 3 mM MTS-verapamil.
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ABCB1 p.Phe728Cys 16813563:140:7
status: NEWX
ABCB1 p.Phe728Cys 16813563:140:128
status: NEWX
ABCB1 p.Phe728Cys 16813563:140:234
status: NEW148 The activity of untreated mutant F728C was stimulated 6.0-fold in the presence of verapamil (Figure 4).
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ABCB1 p.Phe728Cys 16813563:148:33
status: NEW151 When mutant F728C was treated with MTS-verapamil, its activity could not be increased or decreased further with calcein-AM, demecolcine or trans-(E)-flupentixol (Figure 4B).
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ABCB1 p.Phe728Cys 16813563:151:12
status: NEW154 To distinguish between these possibilities, we compared the properties of mutant Q725C with mutant F728C.
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ABCB1 p.Phe728Cys 16813563:154:99
status: NEW155 The activity of mutant Q725C was very similar to that of mutant F728C when assayed in the presence of calcein-AM, demecolcine, verapamil, cyclosporin A or trans-(E)-flupentixol before and after labelling with MTS-verapamil (Figures 4C and 4D).
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ABCB1 p.Phe728Cys 16813563:155:64
status: NEW161 cysteines facing the drug-binding pocket that may be cross-linked with F728C are L65C(TM1), I306C(TM5) and F343C(TM6) because they were covalently modified with MTS-verapamil (L65C and I306C) or with MTS-Rhodamine (F343C).
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ABCB1 p.Phe728Cys 16813563:161:71
status: NEW177 Cross-linking was due to linkage between Cys343 and Cys728 because cross-linked product was not detected on SDS/ PAGE when membranes prepared from HEK-293 cells transfected with the F343C or F728C single cysteine mutant cDNAs, or cotransfected with the F343C and F728C mutant cDNAs, were treated with the homobifunctional cross-linkers (results not shown).
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ABCB1 p.Phe728Cys 16813563:177:191
status: NEWX
ABCB1 p.Phe728Cys 16813563:177:263
status: NEW232 We found that the Km of mutant F728C for ATP remained at about 1 mM before and after modification with MTS-verapamil (results not shown).
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ABCB1 p.Phe728Cys 16813563:232:31
status: NEW[hide] Inhibition of multidrug resistance by adamantylgb3... J Biol Chem. 2008 Feb 22;283(8):4501-11. Epub 2007 Nov 13. De Rosa MF, Ackerley C, Wang B, Ito S, Clarke DM, Lingwood C
Inhibition of multidrug resistance by adamantylgb3, a globotriaosylceramide analog.
J Biol Chem. 2008 Feb 22;283(8):4501-11. Epub 2007 Nov 13., 2008-02-22 [PMID:18003606]
Abstract [show]
Multidrug resistance (MDR) via the ABC drug transporter (ABCB1), P-glycoprotein (P-gp/MDR1) overexpression, is a major obstacle in cancer chemotherapy. Many inhibitors reverse MDR but, like cyclosporin A (CsA), have significant toxicities. MDR1 is also a translocase that flips glucosylceramide inside the Golgi to enhance neutral glycosphingolipid (GSL) synthesis. We observed partial MDR1/globotriaosylceramide (Gb3) cell surface co-localization, and GSL removal depleted cell surface MDR1. MDR1 may therefore interact with GSLs. AdamantylGb3, a water-soluble Gb3 mimic, but not other GSL analogs, reversed MDR1-MDCK cell drug resistance. Cell surface MDR1 was up-regulated 1 h after treatment with CsA or adaGb3, but at 72 h, cell surface expression was lost. Intracellular MDR1 accumulated throughout, suggesting long term defects in plasma membrane MDR1 trafficking. AdaGb3 or CsA rapidly reduced rhodamine 123 cellular efflux. MDR1 also mediates gastrointestinal epithelial drug efflux, restricting oral bioavailability. Vinblastine apical-to-basal transport in polarized human intestinal C2BBe1 cells was significantly increased when adaGb3 was added to both sides, or to the apical side only, comparable with verapamil, a standard MDR1 inhibitor. Disulfide cross-linking of mutant MDR1s showed no binding of adaGb3 to the MDR1 verapamil/cyclosporin-binding site between surface proximal helices of transmembrane segments (TM) 6 and TM7, but rather to an adjacent site nearer the center of TM6 and the TM7 extracellular face, i.e. close to the bilayer leaflet interface. Verotoxin-mediated Gb3 endocytosis also up-regulated total MDR1 and inhibited drug efflux. Thus, a functional interplay between membrane Gb3 and MDR1 provides a more physiologically based approach to MDR1 regulation to increase the bioavailability of chemotherapeutic drugs.
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No. Sentence Comment
270 C, panel i, membranes prepared from HEK 293 cells expressing mutant L339C/F728C were preincubated for 15 min at 22 °C with different concentrations of adaGb3 (0-500 M) (lanes 2-6).
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ABCB1 p.Phe728Cys 18003606:270:74
status: NEW[hide] Arginines in the first transmembrane segment promo... J Biol Chem. 2008 Sep 5;283(36):24860-70. Epub 2008 Jul 2. Loo TW, Bartlett MC, Clarke DM
Arginines in the first transmembrane segment promote maturation of a P-glycoprotein processing mutant by hydrogen bond interactions with tyrosines in transmembrane segment 11.
J Biol Chem. 2008 Sep 5;283(36):24860-70. Epub 2008 Jul 2., 2008-09-05 [PMID:18596043]
Abstract [show]
A key goal is to correct defective folding of mutant ATP binding cassette (ABC) transporters, as they cause diseases such as cystic fibrosis. P-glycoprotein (ABCB1) is a useful model system because introduction of an arginine at position 65 of the first transmembrane (TM) segment could repair folding defects. To determine the mechanism of arginine rescue, we first tested the effects of introducing arginines at other positions in TM1 (residues 52-72) of a P-glycoprotein processing mutant (G251V) that is defective in folding and trafficking to the cell surface (20% maturation efficiency). We found that arginines introduced into one face of the TM1 helix (positions 52, 55, 56, 59, 60, 62, 63, 66, and 67) inhibited maturation, whereas arginines on the opposite face of the helix promoted (positions 64, 65, 68, and 71) or had little effect (positions 61, and 69) on maturation. Arginines at positions 61, 64, 65, and 68 appeared to lie close to the drug binding sites as they reduced the apparent affinity for drug substrates such as vinblastine and verapamil. Therefore, arginines that promoted maturation may face an aqueous drug translocation pathway, whereas those that inhibited maturation may face the lipid bilayer. The highest maturation efficiencies (60-85%) were observed with the Arg-65 and Arg-68 mutants. Mutations that removed hydrogen bond acceptors (Y950F/Y950A or Y953F/Y953A) in TM11 predicted to lie close to Arg-65 or Arg-68 inhibited maturation but did not affect maturation of the G251V parent. Therefore, arginine may rescue defective folding by promoting packing of the TM segments through hydrogen bond interactions.
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No. Sentence Comment
194 TABLE 2 Concentrations of drug substrates required to inhibit cross-linking by 50% Mutant Vinblastine Cyclosporin A Rhodamine B M M M L339C/F728C 0.5 Ϯ 0.2a 0.8 Ϯ 0.3 52 Ϯ 14 G64R/L339C/F728C 53 Ϯ 15b 1.5 Ϯ 0.4 61 Ϯ 10 M68R/L339C/F728C 266 Ϯ 62b 1.3 Ϯ 0.3 57 Ϯ 7 V71R/L339C/F728C 0.6 Ϯ 0.2 0.8 Ϯ 0.2 57 Ϯ 10 a Each value is the mean Ϯ S.D. (n ϭ 3-4 separate cross-linking experiments).
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ABCB1 p.Phe728Cys 18596043:194:164
status: NEWX
ABCB1 p.Phe728Cys 18596043:194:228
status: NEWX
ABCB1 p.Phe728Cys 18596043:194:290
status: NEWX
ABCB1 p.Phe728Cys 18596043:194:352
status: NEW[hide] Multiple transport-active binding sites are availa... PLoS One. 2013 Dec 5;8(12):e82463. doi: 10.1371/journal.pone.0082463. eCollection 2013. Chufan EE, Kapoor K, Sim HM, Singh S, Talele TT, Durell SR, Ambudkar SV
Multiple transport-active binding sites are available for a single substrate on human P-glycoprotein (ABCB1).
PLoS One. 2013 Dec 5;8(12):e82463. doi: 10.1371/journal.pone.0082463. eCollection 2013., [PMID:24349290]
Abstract [show]
P-glycoprotein (Pgp, ABCB1) is an ATP-Binding Cassette (ABC) transporter that is associated with the development of multidrug resistance in cancer cells. Pgp transports a variety of chemically dissimilar amphipathic compounds using the energy from ATP hydrolysis. In the present study, to elucidate the binding sites on Pgp for substrates and modulators, we employed site-directed mutagenesis, cell- and membrane-based assays, molecular modeling and docking. We generated single, double and triple mutants with substitutions of the Y307, F343, Q725, F728, F978 and V982 residues at the proposed drug-binding site with cys in a cysless Pgp, and expressed them in insect and mammalian cells using a baculovirus expression system. All the mutant proteins were expressed at the cell surface to the same extent as the cysless wild-type Pgp. With substitution of three residues of the pocket (Y307, Q725 and V982) with cysteine in a cysless Pgp, QZ59S-SSS, cyclosporine A, tariquidar, valinomycin and FSBA lose the ability to inhibit the labeling of Pgp with a transport substrate, [(125)I]-Iodoarylazidoprazosin, indicating these drugs cannot bind at their primary binding sites. However, the drugs can modulate the ATP hydrolysis of the mutant Pgps, demonstrating that they bind at secondary sites. In addition, the transport of six fluorescent substrates in HeLa cells expressing triple mutant (Y307C/Q725C/V982C) Pgp is also not significantly altered, showing that substrates bound at secondary sites are still transported. The homology modeling of human Pgp and substrate and modulator docking studies support the biochemical and transport data. In aggregate, our results demonstrate that a large flexible pocket in the Pgp transmembrane domains is able to bind chemically diverse compounds. When residues of the primary drug-binding site are mutated, substrates and modulators bind to secondary sites on the transporter and more than one transport-active binding site is available for each substrate.
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No. Sentence Comment
55 For biochemical studies, crude membranes were prepared from High-Five insect cells infected with baculovirus coding for cysless WT, single mutants Y307C, F343C, Q725C, F728C, F978C, V982C, double mutants Y307C/V982C, F343C/V982C, Q725C/V982C, F728C/V982C, and a triple mutant Y307C/Q725C/V982C.
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ABCB1 p.Phe728Cys 24349290:55:168
status: NEWX
ABCB1 p.Phe728Cys 24349290:55:243
status: NEW73 Inhibition of IAAP labeling for single mutants Q725C, Y307C, F728C and V982C (upper graphs) and for double Q725C/V982C, Y307C/V982C, F728C/V982C, and triple Y307C/Q725C/V982C (lower graphs) mutants at different concentrations of (A) CsA and (B) tariquidar, are shown. Inhibition of IAAP labeling for cysless WT is included in all graphs, as a reference.
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ABCB1 p.Phe728Cys 24349290:73:61
status: NEWX
ABCB1 p.Phe728Cys 24349290:73:133
status: NEW82 However a majority of the mutants show low basal activity; F728C/V982C shows the lowest (4 &#b1;1.6 nmol Pi/min/mg protein) while V982C and F978C shows fairly low activity (11 &#b1; 2.2 and 13 &#b1; 0.6, respectively).
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ABCB1 p.Phe728Cys 24349290:82:59
status: NEW90 Mutation(s) CsA Tariquidar Max Inhibition (%) IC50 (&#b5;M) Max Inhibition (%) IC50 (&#b5;M) Cysless WT 86 &#b1; 3 0.05 &#b1; 0.01 97 &#b1; 4 0.14 &#b1; 0.03 Q725C 24 &#b1; 4 -- 37 -- Q725C/V982C 11 -- 22 -- Y307C 35 &#b1; 2 -- ND -- Y307C/V982C 46 -- ND -- F728C 48 -- 40 -- F728C/V982C 49 -- ND -- V982C 56 0.40 64 0.70 Y307C/Q725C/ V982C 12 -- 23 -- F978C 86 0.54 73 3.6 Mean values with standard errors are reported when more than two experiments were carried out; otherwise only average values are reported.
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ABCB1 p.Phe728Cys 24349290:90:258
status: NEWX
ABCB1 p.Phe728Cys 24349290:90:276
status: NEW95 FSBA also stimulates the ATP hydrolysis of most of the mutants, with the exception of the double F728C/V982C and the triple Y307C/Q725C/V982C mutant.
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ABCB1 p.Phe728Cys 24349290:95:97
status: NEW141 As expected, the corresponding double mutants (Q725C/V982C; F728C/V982C; Figure 3.
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ABCB1 p.Phe728Cys 24349290:141:60
status: NEW175 Mutation(s) Cell surface expression Transport function CalAM BD-PRA NBD-CsA Rh123 Dauno BD-PAC Y307C 100 90-100 80-90 90-100 90-100 90-100 90-100 Q725C 100 90-100 90-100 90-100 90-100 90-100 90-100 F728C 100 90-100 80-90 90-100 90-100 90-100 90-100 V982C 100 90-100 80-100 <10 90-100 90-100 90-100 F343C 50-60 90-100 80-100 90-100 90-100 90-100 90-100 F978C 100 90-100 90-100 90-100 90-100 90-100 90-100 Y307C/ V982C 100 90-100 50-60 50-60 90-100 90-100 90-100 Q725C/ V982C 100 90-100 80-90 <20 90-100 90-100 90-100 F728C/ V982C 30-40 55-65 30-40 <20 70-80 50-60 90-100 F343C/ V982C 70-80 90-100 80-90 <20 90-100 90-100 90-100 Y307/ Q725C/ V982C 100 90-100 30-40 50-60 70-80 60-70 90-100 For cell surface expression, the cells were incubated with MRK-16 antibody for 30 min followed by FITC-labeled anti-mouse secondary antibody for 30 min.
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ABCB1 p.Phe728Cys 24349290:175:198
status: NEWX
ABCB1 p.Phe728Cys 24349290:175:516
status: NEW240 The partial inhibition of IAAP labeling observed for single mutants (Y307C, Q725C, F728C, and V982C) and even double mutants (Y307C/V982C, Q725C/V982C, F728C/V982C) is indicative of some drug interaction with Pgp (Figure 1).
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ABCB1 p.Phe728Cys 24349290:240:83
status: NEWX
ABCB1 p.Phe728Cys 24349290:240:152
status: NEW