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. 2010 Aug 15;80(4):448-54.
doi: 10.1016/j.bcp.2010.04.030. Epub 2010 May 6.

The role of the N-terminus of mammalian copper transporter 1 in the cellular accumulation of cisplatin

Christopher A Larson  1 , Preston L Adams, Danielle D Jandial, Brian G Blair, Roohangiz Safaei, Stephen B Howell
Affiliations

The role of the N-terminus of mammalian copper transporter 1 in the cellular accumulation of cisplatin

Christopher A Larson et al. Biochem Pharmacol. .

Erratum in

  • Biochem Pharmacol. 2010 Dec 1;80(11):1768

Abstract

The mammalian copper transporter 1 (CTR1) is responsible for the uptake of copper (Cu) from the extracellular space, and has been shown to play a major role in the initial accumulation of platinum-based drugs. In this study we re-expressed wild type and structural variants of hCTR1 in mouse embryo fibroblasts in which both alleles of mCTR1 had been knocked out (CTR1(-/-)) to examine the role of the N-terminal extracellular domain of hCTR1 in the accumulation of cisplatin (cDDP) VSports手机版. Deletion of either the first 45 amino acids or just the (40)MXXM(45) motif in the N-terminal domain did not alter subcellular distribution or the amount of protein in the plasma membrane but it eliminated the ability of hCTR1 to mediate the uptake of Cu. In contrast it only partially reduced cDDP transport capacity. Neither of these structural changes prevented cDDP from triggering the rapid degradation of hCTR1. However, they did alter the potency of the cDDP that achieved cell entry, possibly reflecting the fact that hCTR1 may mediate the transport of cDDP both through the pore it forms in the plasma membrane and via endocytosis. We conclude that cDDP interacts with hCTR1 both at (40)MXXM(45) and at sites outside the N-terminal domain that produce the conformational changes that trigger degradation. .

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Figures

Figure 1
Figure 1
Schematic diagram of the amino acid sequence of hCTR1. Boxes highlight the H1, M1, H2 and M2 motifs.
Figure 2
Figure 2
Re-expression of wild type and variants forms of myc-hCTR1 in CTR1−/− cells. A. Relative mRNA levels measured by qRT-PCR. B. Representative western blot showing the expression of myc-tagged hCTR1. C. Micrograph demonstrating the uniform expression of the myc-tagged hCTR1 protein (60× magnification). Panel A, CTR1−/−/wt cells; panel B, CTR1−/−/M2 cells; panel C, CTR1−/−/Truncated cells. Vertical bars, ± SEM.
Figure 3
Figure 3
Cu accumulation and cytotoxicity. A, total basal Cu; B, total Cu following 1 h exposure to 100 µM Cu; C, inhibition of growth of MEF cells during 96 h continuous exposure to varying concentrations of Cu. (●), CTR1−/−; (□), myc-CTR1−/−/wt; (▲), myc-CTR1−/−/M2; (▼), myc-CTR1−/−/Truncated. Each value represents the mean of no less than 3 independent experiments each performed with 3 separate cultures. Vertical bars, ± SEM.
Figure 4
Figure 4
cDDP accumulation and cytotoxicity. A, Net accumulation of Pt in MEF cells following 5 min exposure to 30 µM cDDP. B, Inhibition of growth of MEF cells following 5 minute exposure to varying concentrations of cDDP. (●), CTR1−/−; (□), myc-CTR1−/−/wt; (▲), myc-CTR1−/−/M2; (▼), myc-CTR1−/−/Truncated. All values represent means of 6 independent experiments each containing triplicate cultures. Vertical lines, ± SEM.
Figure 5
Figure 5
Micrographs of MEF cells expressing hCTR1. All panels are 20×. Panels A–C, no treatment; panels D – F, cells exposed to 30 µM CDDP treatment for 15 minutes prior to fixing. Panels A and D, CTR1−/−/wt cells; panels B and E, CTR1−/−/M2 cells; panels C and F, CTR1−/−/Truncated cells.
See this image and copyright information in PMC

References

    1. Madsen E, Gitlin JD. Copper deficiency. Curr Opin Gastroenterol. 2007;23:187–192. - PubMed
    1. Balamurugan K, Schaffner W. Copper homeostasis in eukaryotes: teetering on a tightrope. Biochim Biophys Acta. 2006;1763:737–746. - PubMed
    1. Bertinato J, L'Abbe MR. Maintaining copper homeostasis: regulation of copper-trafficking proteins in response to copper deficiency or overload. J Nutr Biochem. 2004;15:316–322. - "V体育官网入口" PubMed
    1. Kim BE, Nevitt T, Thiele DJ. Mechanisms for copper acquisition, distribution and regulation. Nat Chem Biol. 2008;4:176–185. - PubMed
    1. Hamza I, Prohaska J, Gitlin JD. Essential role for Atox1 in the copper-mediated intracellular trafficking of the Menkes ATPase. Proc Natl Acad Sci U S A. 2003;100:1215–1220. - PMC - PubMed

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