ABCMdb

PMID: 25036722

Szafraniec MJ, Szczygiel M, Urbanska K, Fiedor L
Determinants of the activity and substrate recognition of breast cancer resistance protein (ABCG2).
Drug Metab Rev. 2014 Nov;46(4):459-74. doi: 10.3109/03602532.2014.942037. Epub 2014 Jul 18., [PubMed]

Sentences

No. Mutations Sentence Comment

68 ABCG2 p.Arg482Thr ABCG2 p.Arg482Gly This effect was observed only for Arg482 -BCRP (WT protein), with no such influence on the Arg482 Gly or Arg482 Thr variants. Login to comment 156 ABCG2 p.Arg482Thr While taxanes act only against WT BCRP, no effect was found on the Arg482 Thr mutant. Login to comment 163 ABCG2 p.Arg482Thr ABCG2 p.Arg482Gly The role of residue 482 The substitution of Arg482 by Thr or Gly results in the capability of BCRP-overexpressing cells to efflux rhodamine 123 and doxorubicin (Honjo et al., 2001), but irrespective of residue 482, the cells were able to transport mitoxantrone. Login to comment 164 ABCG2 p.Arg482Thr ABCG2 p.Arg482Gly Moreover, the Arg482 Thr variant seemed to enhance the resistance of BCRP-transfected HEK-293 cells to anthracyclines, whereas the Arg482 Gly variant passed on diminished resistance in this cell line to SN-38 and topotecan. Login to comment 171 ABCG2 p.Arg482Lys Many other amino acids, i.e. Gly, Ile, Met, Ser, Thr, Asp, Asn, Lys and Tyr, have been substituted at position 482, and all of these variants, except for Arg482 Lys, transported mitoxantrone, but only the WT protein transported methotrexate. Login to comment 172 ABCG2 p.Arg482Lys ABCG2 p.Arg482Tyr Rhodamine was effluxed by most of these variants except for Arg482 Lys, Arg482 Tyr and WT protein. Login to comment 173 ABCG2 p.Arg482Lys ABCG2 p.Arg482Tyr Arg482 Lys and Arg482 Tyr did not drive out Hoechst 33342 either (O &#a8; zvegy-Laczka et al., 2005). Login to comment 175 ABCG2 p.Arg482Lys Out of 19 BCRP variants, with different standard amino acids at position 482, only Arg482 Lys-BCRP is completely devoid of transport capability. Login to comment 183 ABCG2 p.Arg482Thr ABCG2 p.Arg482Gly There were also significant differences in ATPase activity among the three BCRP variants, WT form, Arg482 Gly and Arg482 Thr, expressed in the Sf9 cell membranes and stimulated by several substrates. Login to comment 186 ABCG2 p.Arg482Thr ABCG2 p.Arg482Gly The ATPase activity of WT BCRP stimulated by mitoxantrone or estradiol-17b-glucuronide was greatly enhanced in cholesterol-enriched membranes, but no such an effect was observed in the Arg482 Gly or Arg482 Thr variants (Telbisz et al., 2007). Login to comment 192 ABCG2 p.His457Ala The replacement of Lys452 or His457 by Ala considerably enhanced the transport of mitoxantrone, BODIPY-prazosin and Hoechst 33342, whereas substitutions of Lys453 and Arg465 significantly decreased the transport of mitoxantrone, BODIPY-prazosin, Hoechst 33342, doxorubicin, SN-38 and rhodamine 123. Login to comment 196 ABCG2 p.Lys86Met Studies on Lys86 Met-BCRP, catalytically inactive, but able to bind ATP, revealed that this mutation has no influence on the oligomerization properties of the transporter but prevents the stimulation of ATPase activity by prazosin. Login to comment 197 ABCG2 p.Lys86Met The ability of cells stably transfected with Lys86 Met-BCRP to transport mitoxantrone was comparable to that of non-transfected cells. Login to comment 198 ABCG2 p.Lys86Met A co-transfection of HEK293 with both WT and Lys86 Met proteins resulted in a 60% loss of ATPase activity. Login to comment 199 ABCG2 p.Lys86Met A possible explanation of this is that the Lys86 Met protein oligomerizes with the WT protein creating a non-functional complex, as two active NBDs are necessary for ATP hydrolysis (Henriksen et al., 2005b). Login to comment 201 ABCG2 p.Arg482Thr ABCG2 p.Arg482Gly ABCG2 p.Gln141Lys ABCG2 p.Val12Met ABCG2 p.Ile206Leu ABCG2 p.Asn590Tyr ABCG2 p.Gln166Glu ABCG2 p.Phe208Ser ABCG2 p.Asp620Asn ABCG2 p.Thr153Met ABCG2 p.Ser441Asn ABCG2 p.Phe489Leu ABCG2 p.Phe431Leu ABCG2 p.Gly51Cys ABCG2 p.Ser248Pro ABCG2 p.Phe571Ile To elucidate the significance of this polymorphism for porphyrin transport, a set of 18 variants of BCRP (Val12 Met, Gly51 Cys, Gln126 stop, Gln141 Lys, Thr153 Met, Gln166 Glu, Ile206 Leu, Phe208 Ser, Ser248 Pro, Glu334 stop, Phe431 Leu, Ser441 Asn, Arg482 Gly, Arg482 Thr, Phe489 Leu, Phe571 Ile, Asn590 Tyr and Asp620 Asn) have been expressed in insect cells. Login to comment 203 ABCG2 p.Phe208Ser ABCG2 p.Ser248Phe A model study on plasma membrane vesicles showed that mutations the Glu126 stop, Phe208 Ser, Ser248 Phe, Glu334 stop and Ser441 Asn lead to an inability to transport hematoporphyrin. Login to comment 204 ABCG2 p.Phe489Leu ABCG2 p.Phe431Leu In the Phe489 Leu mutant transport was also impaired, while the Ser441 Asn variant lost the ability to transport methotrexate and the Phe431 Leu variant seemed to transport hematoporphyrin normally but showed no transport of methotrexate. Login to comment 205 ABCG2 p.Phe489Leu The Phe489 Leu variant did not transport methotrexate but maintained hematoporphyrin transport at a low level (10% of the WT protein). Login to comment 206 ABCG2 p.Phe208Ser ABCG2 p.Phe489Leu ABCG2 p.Ser248Phe Moreover, Flp-In-293 cells expressing the variants Phe208 Ser, Ser248 Phe, Ser441 Asn and Phe489 Leu were light sensitive when treated with Pheide. Login to comment 209 ABCG2 p.Arg482Thr ABCG2 p.Arg482Thr ABCG2 p.Arg482Gly ABCG2 p.Arg482Gly ABCG2 p.Lys86Met ABCG2 p.Asn590Tyr ABCG2 p.Phe208Ser ABCG2 p.Arg482Lys ABCG2 p.Gly406Leu ABCG2 p.Gly410Leu ABCG2 p.Gly410Ala ABCG2 p.Gly406Ala ABCG2 p.Ser441Asn ABCG2 p.Ser441Asn ABCG2 p.Phe489Leu ABCG2 p.Phe431Leu ABCG2 p.Cys592Ala ABCG2 p.Cys608Ala ABCG2 p.Cys603Ser ABCG2 p.Cys603Ser ABCG2 p.Cys592Ser ABCG2 p.Cys592Ser ABCG2 p.Cys608Ser ABCG2 p.Cys608Ser ABCG2 p.Glu211Gln ABCG2 p.His457Ala ABCG2 p.Arg465Ala ABCG2 p.Lys452Ala ABCG2 p.Pro392Ala ABCG2 p.Ser248Phe ABCG2 p.Lys453Ala Position Type of mutation Effect on the transporter References NBD Lys 86 Met (i) No stimulation of the ATPase activity by prazosin; (ii) no influence on the transport of mitoxantrone Henriksen et al. (2005b) Glu 126 stop, Phe 208 Ser, Ser 248 Phe, Glu 334 stop Inability to transport hematoporphyrin Tamura et al. (2006) Glu 211 Gln Complete abolishment of the ATPase activity and methotrexate transport Hou et al. (2009) Pro 392 Ala Significant reduction in the efflux activity of mitoxantrone, BODIPY-prazosin and Hoechst 33342 Ni et al. (2011) TM1 Gly 406 Ala Gly 410 Ala No influence on the activity of the transporter Polgar et al. (2004) Gly 406 Leu Gly 410 Leu (i) Loss of the ability to transport rhodamine123; (ii) impaired transport of mitoxantrone, Pheide and BODIPY-prazosin Polgar et al. (2004) Extracellular loop 1 Phe 431 Leu (i) Loss of the ability to transport methotrexate; (ii) 10% level of hematoporphyrin transport compared to the WT protein Tamura et al. (2006) Ser 441 Asn Inability to transport hematoporphyrin Tamura et al. (2006) Ser 441 Asn Loss of the ability to transport methotrexate Tamura et al. (2006) TM2 Lys 452 Ala His 457 Ala Increase in transport of mitoxantrone, BODIPY-prazosin and Hoechst 33342 Cai et al. (2010) Lys 453 Ala Arg 465 Ala Decrease in transport of mitoxantrone, BODIPY-prazosin, Hoechst 33342, doxorubicin, SN-38 and rhodamine 123 Cai et al. (2010) TM3 Arg 482 Gly Arg 482 Thr (i) No change in the inhibitory activity of lapatinib; (ii) about two times greater inhibition by ritonavir, saquinavir and nalfinavir than in the WT variant; (iii) gaining the ability to transport rhodamine123 and doxorubicin; (iv) no influence on the transport of mitoxantrone; (v) loss of the ability to transport methotrexate Dai et al. (2008), Gupta et al. (2004), Honjo et al. (2001), Mitomo et al. (2003) Arg 482 Thr (i) Lower IC 50 of cyclosporine A for mutant than for WT variant; (ii) lower elacridar inhibition potency Xia et al. (2007) Arg 482 Lys Complete loss of transport activity Ejendal et al. (2006) Phe 489 Leu Impaired transport of porphyrins, no transport of methotrexate Tamura et al. (2006) Extracellular loop 3 Asn 590 Tyr Over twice reduced transport of mitoxantrone, topotecan, daunorubicin and rhodamine 123 Vethanayagam et al. (2005) Cys 592 Ala/Cys 608 Ala (i) Transport of mitoxantrone almost unchanged; (ii) transport of BODIPY-prazosin significantly impaired Henriksen et al. (2005a) Extracellular loop 3 Cys 603 Ser Cys 592 Ser/Cys 608 Ser Cys 592 Ser/Cys 603 Ser/Cys 608 Ser Diminished susceptibility to the inhibitory activity of fumitremorgin C Shigeta et al. (2010) Cys-less Arg 482 Gly-BCRP Complete loss of the ability to efflux mitoxantrone Liu et al. (2008b) The positions of the amino acid residues refer to the topological model of BCRP proposed by Wang et al. (2009). Login to comment 212 ABCG2 p.Asn590Tyr ABCG2 p.Asp620Asn The naturally occurring mutations, Asn590 Tyr and Asp620 Asn, predicted to be localized in the extracellular region linking the TM5 and the TM6 domains (Wang et al., 2009), were also analyzed in HEK-293 cells transfected with BCRP bearing these substitutions. Login to comment 213 ABCG2 p.Asn590Tyr Asn590 Tyr BCRP showed transport activity twice as low as that of the WT protein. Login to comment 214 ABCG2 p.Asn590Tyr ABCG2 p.Asp620Asn The efflux ability of Asp620 Asn-BCRP was also reduced, but not as much as in Asn590 Tyr BCRP. Login to comment 221 ABCG2 p.Gly406Leu ABCG2 p.Gly410Leu The substitution of a single or both Gly residues by Leu in this motif resulted in a loss of transport for rhodamine 123, and impaired transport of mitoxantrone, Pheide and BODIPY-prazosin, in particular, in the double mutant (Gly406 Leu/ Gly410 Leu). Login to comment 226 ABCG2 p.Cys603Ala ABCG2 p.Cys608Ala The substitution of Cys603 by Ala caused the transporter to migrate electrophoretically as a monomer, which is not the case when substituting Cys592 or Cys608 by Ala. Login to comment 227 ABCG2 p.Cys592Ala ABCG2 p.Cys608Ala A double mutant protein Cys592 Ala/Cys608 Ala was rendered unable to transport BODIPY-prazosin, while the transport of mitoxantrone remained almost unchanged. Login to comment 230 ABCG2 p.Cys603Ser ABCG2 p.Cys603Ser ABCG2 p.Cys603Ser ABCG2 p.Cys592Ser ABCG2 p.Cys592Ser ABCG2 p.Cys592Ser ABCG2 p.Cys608Ser ABCG2 p.Cys608Ser ABCG2 p.Cys608Ser Cys592 Ser/Cys603 Ser-BCRP and Cys592 Ser/Cys608 Ser-BCRP were detected as dimers, while Cys603 Ser/Cys608 Ser-BCRP and Cys592 Ser/Cys603 Ser/Cys608 Ser-BCRP as monomers, suggesting that no other Cys are involved in dimerization. Login to comment 231 ABCG2 p.Cys603Ser ABCG2 p.Cys592Ser ABCG2 p.Cys608Ser At the same time, cells transfected with a triple mutant, Cys592 Ser/Cys603 Ser/Cys608 Ser-BCRP, showed significant drug resistance and a low accumulation of mitoxantrone which indicated that dimer formation might not be required for BCRP functioning as a transporter. Login to comment 241 ABCG2 p.Arg482Lys Because the Arg482 Lys variant is completely inactive, it seems likely that residue 482 confers the transport activity on BCRP. Login to comment