The N-terminus of the human copper transporter 1 (hCTR1) is localized extracellularly, and interacts with itself

Adriana E.M. KLOMP; Jenneke A. JUIJN; Linda T.M. van der GUN; Inge E.T. van den BERG; Ruud BERGER; Leo W.J. KLOMP

doi:10.1042/bj20021128

The N-terminus of the human copper transporter 1 (hCTR1) is localized extracellularly, and interacts with itself

Biochemical Journal ◽

10.1042/bj20021128 ◽

2003 ◽

Vol 370 (3) ◽

pp. 881-889 ◽

Cited By ~ 67

Author(s):

Adriana E.M. KLOMP ◽

Jenneke A. JUIJN ◽

Linda T.M. van der GUN ◽

Inge E.T. van den BERG ◽

Ruud BERGER ◽

...

Keyword(s):

Glycosylation Site ◽

Media Analysis ◽

Growth Media ◽

Deletion Mapping ◽

Copper Binding ◽

Copper Transporter ◽

C Terminus ◽

N Terminus ◽

Multiple Regions ◽

Copper Transporter 1

We have used indirect immunofluorescense studies and glycosylation-site insertion and deletion mapping to characterize the topology of human copper transporter 1 (hCTR1), the putative human high-affinity copper-import protein. Both approaches indicated that hCTR1 contains three transmembrane domains and that the N-terminus of hCTR1, which contains several putative copper-binding sites, is localized extracellularly, whereas the C-terminus is exposed to the cytosol. Based on previous observations that CTR1 proteins form high-molecular-mass complexes, we investigated directly whether CTR1 proteins interact with themselves. Yeast two-hybrid studies showed that interaction of yeast, mouse, rat and human CTR1 occurs at the sites of their N-terminal domains, and is not dependent on the copper concentration in the growth media. Analysis of deletion constructs indicated that multiple regions in the N-terminus are essential for this self-interaction. In contrast, the N-terminal tail of the presumed low-affinity copper transporter, hCTR2, does not interact with itself. Taken together, these results suggest that CTR1 spans the membrane at least six times, permitting formation of a channel, which is consistent with its proposed role as a copper transporter.

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Model Peptide Studies Reveal a Mixed Histidine-Methionine Cu(I) Binding Site at the N-Terminus of Human Copper Transporter 1

Inorganic Chemistry ◽

10.1021/acs.inorgchem.5b01162 ◽

2015 ◽

Vol 54 (17) ◽

pp. 8544-8551 ◽

Cited By ~ 26

Author(s):

M. Jake Pushie ◽

Katharine Shaw ◽

Katherine J. Franz ◽

Jason Shearer ◽

Kathryn L. Haas

Keyword(s):

Binding Site ◽

Model Peptide ◽

Copper Transporter ◽

N Terminus ◽

Copper Transporter 1

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Interaction of Copper Toxicity and Oxidative Stress in Campylobacter jejuni

Journal of Bacteriology ◽

10.1128/jb.00208-18 ◽

2018 ◽

Vol 200 (21) ◽

Cited By ~ 3

Author(s):

Susan P. Gardner ◽

Jonathan W. Olson

Keyword(s):

Oxidative Stress ◽

Campylobacter Jejuni ◽

Copper Toxicity ◽

Foodborne Pathogen ◽

Growth Media ◽

Avian Host ◽

Copper Binding ◽

Copper Transporter ◽

Content Type ◽

Metabolic Requirement

ABSTRACT Copper is both a required micronutrient and a source of toxicity in most organisms, including Campylobacter jejuni. Two proteins expressed in C. jejuni (termed CopA and CueO) have been shown to be a copper transporter and multicopper oxidase, respectively. We have isolated strains with mutations in these genes, and here we report that they were more susceptible to both the addition of copper in the growth media and to induced oxidative stress. Both mutant strains were defective in colonization of an avian host, and copper in the feed exacerbated the colonization deficiency. Overexpression of a cytoplasmic peptide derived from the normally periplasmic copper-binding region of CueO also caused copper intolerance compared to nonexpressing strains or strains expressing the non-copper-binding versions of the peptide. Taken together, the results indicate that copper toxicity in C. jejuni is due to a failure to effectively sequester cytoplasmic copper, resulting in an increase in copper-mediated oxidative damage. IMPORTANCE Copper is a required micronutrient for most aerobic organisms, but it is universally toxic at elevated levels. These organisms use homeostatic mechanisms that allow for cells to acquire enough of the element to sustain metabolic requirements while ensuring that lethal levels cannot build up in the cell. Campylobacter jejuni is an important foodborne pathogen that typically makes its way into the food chain through contaminated poultry. C. jejuni has a metabolic requirement for copper and encodes a copper detoxification system. In the course of studying this system, we have learned that it is important for avian colonization. We have also gained insight into how copper exerts its toxic effects in C. jejuni by promoting oxidative stress.

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Cellular glutathione plays a key role in copper uptake mediated by human copper transporter 1

AJP Cell Physiology ◽

10.1152/ajpcell.00417.2012 ◽

2013 ◽

Vol 304 (8) ◽

pp. C768-C779 ◽

Cited By ~ 98

Author(s):

Edward B. Maryon ◽

Shannon A. Molloy ◽

Jack H. Kaplan

Keyword(s):

Initial Rate ◽

Hek293 Cells ◽

Binding Motif ◽

Copper Binding ◽

Experimental Conditions ◽

Copper Transporter ◽

Copper Chaperones ◽

Copper Transporter 1 ◽

Cu Uptake

Copper is an essential micronutrient. Following entry via the human copper transporter 1 (hCTR1), copper is delivered to several copper chaperones, which subsequently transfer the metal to specific targets via protein:protein interactions. It is has been assumed, but not demonstrated, that chaperones acquire copper directly from hCTR1. However, some reports have pointed to an intermediary role for glutathione (GSH), an abundant copper-binding tri-peptide. To address the issue of how transported copper is acquired by the copper chaperones in vivo, we measured the initial rate of64Cu uptake in cells in which the cellular levels of copper chaperones or GSH were substantially depleted or elevated. Knockdown or overexpression of copper chaperones ATOX1, CCS, or both had no effect on the initial rate of64Cu entry into HEK293 cells having endogenous or overexpressed hCTR1. In contrast, depleting cellular GSH using l-buthionine-sulfoximine (BSO) caused a 50% decrease in the initial rate of64Cu entry in HEK293 cells and other cell types. This decrease was reversed by washout of BSO or GSH replenishment with a permeable ester. BSO treatment under our experimental conditions had no significant effects on the viability, ATP levels, or metal content of the cells. Attenuated64Cu uptake in BSO was not due to oxidation of the cysteine in the putative metal-binding motif (HCH) at the intracellular hCTR1 COOH terminus, because a mutant lacking this motif was fully active, and64Cu uptake was still reduced by BSO treatment. Our data suggest that GSH plays an important role in copper handling at the entry step.

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Corrigendum to “The role of the N-terminus of mammalian copper transporter 1 in the cellular accumulation of cisplatin” [Biochem. Pharmacol. 80 (2010) 448–454]

Biochemical Pharmacology ◽

10.1016/j.bcp.2010.08.006 ◽

2010 ◽

Vol 80 (11) ◽

pp. 1768

Author(s):

Christopher A. Larson ◽

Preston L. Adams ◽

Danielle D. Jandial ◽

Brian G. Blair ◽

Roohangiz Safaei ◽

...

Keyword(s):

Copper Transporter ◽

Cellular Accumulation ◽

N Terminus ◽

Copper Transporter 1

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

Biochemical Pharmacology ◽

10.1016/j.bcp.2010.04.030 ◽

2010 ◽

Vol 80 (4) ◽

pp. 448-454 ◽

Cited By ~ 36

Author(s):

Christopher A. Larson ◽

Preston L. Adams ◽

Danielle D. Jandial ◽

Brian G. Blair ◽

Roohangiz Safaei ◽

...

Keyword(s):

Copper Transporter ◽

Cellular Accumulation ◽

N Terminus ◽

Copper Transporter 1

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Isoform and protein region abnormalities of dysbindin and copper transporter proteins in postmortem schizophrenia substantia nigra

10.1101/343178 ◽

2018 ◽

Author(s):

Kirsten E. Schoonover ◽

Rosalinda C. Roberts

Keyword(s):

Substantia Nigra ◽

Preliminary Investigation ◽

Brain Regions ◽

Specific Protein ◽

Copper Transport ◽

Antipsychotic Treatment ◽

Copper Transporter ◽

Transporter Protein ◽

C Terminus ◽

N Terminus

AbstractObjectiveDysbindin is downregulated in several schizophrenia brain regions and modulates copper transport required for myelination and monoamine metabolism. We sought to determine dysbindin and copper transporter protein expression in schizophrenia subjects.MethodsWe studied the substantia nigra (which exhibits one of the highest copper contents of the human brain) using Western blot analysis. We characterized specific protein domains of copper transporters ATP7A, CTR1, ATP7B, and dysbindin isoforms 1A and 1B/C in postmortem substantia nigra in schizophrenia subjects (n=15) and matched controls (n=11). As a preliminary investigation, we examined medication status in medicated (n=11) versus unmedicated schizophrenia subjects (n=4).ResultsThe combined schizophrenia group exhibited increased levels of C-terminus, but not N-terminus, ATP7A. Schizophrenia subjects expressed less transmembrane CTR1 and dysbindin 1B/C than controls. When subdivided, the increased C-terminus ATP7A protein was present only in medicated subjects versus controls. Unmedicated subjects exhibited less N-terminus ATP7A protein than controls and medicated subjects, suggesting medication-induced rescue of the ATP7A N-terminus. Transmembrane CTR1 was decreased to a similar extent in both treatment groups versus controls, suggesting no medication effect.ConclusionsThese results provide the first evidence of disrupted copper transport into and within schizophrenia nigral cells that may be modulated by specific dysbindin isoforms and antipsychotic treatment.

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Activation of carboplatin and nedaplatin by the N-terminus of human copper transporter 1 (hCTR1)

Chemical Science ◽

10.1039/c2sc20738a ◽

2012 ◽

Vol 3 (11) ◽

pp. 3206 ◽

Cited By ~ 16

Author(s):

Xinghao Wang ◽

Hongyan Li ◽

Xiubo Du ◽

Jack Harris ◽

Zijian Guo ◽

...

Keyword(s):

Copper Transporter ◽

N Terminus ◽

Copper Transporter 1

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Faculty Opinions recommendation of Functional characterization of pkr gene products expressed in cells from mice with a targeted deletion of the N terminus or C terminus domain of PKR.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1008566.108158 ◽

2002 ◽

Author(s):

David Ron

Keyword(s):

Functional Characterization ◽

Gene Products ◽

Targeted Deletion ◽

C Terminus ◽

N Terminus ◽

In Cells

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Preparation and properties of three analogues of [5-leucine]enkephalin, substrates for enzyme conversion studies

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19851329 ◽

1985 ◽

Vol 50 (6) ◽

pp. 1329-1334

Author(s):

Jaroslav Vičar ◽

Linda Servítová ◽

Martin Flegel ◽

Karel Hauzer ◽

Tomislav Barth

Keyword(s):

High Pressure ◽

Liquid Chromatography ◽

Guinea Pig ◽

Ion Exchange Chromatography ◽

Exchange Chromatography ◽

Guinea Pig Ileum ◽

Opioid Activity ◽

C Terminus ◽

N Terminus ◽

Fragment Condensation

Analogues of [5-Leu]enkephalin, prolonged by methionine on the N-terminus or, by lysine or methionine on the C-terminus were prepared by fragment condensation, purified by ion exchange chromatography or high-pressure liquid chromatography. The substances were characterised by their opioid activity in a test on guinea-pig ileum in comparison with the activity of [5-Leu]enkephalin.

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