Abstract

The putative product of CTR1 (SLC31A1 according to the Entrez data base) is regarded as the main candidate for an eukaryotic transmembrane copper importer. The tissue-specific function of mammalian CTR1 is still unknown. A quasi-steady-state level of the CTR1 mRNA was assayed by semiquantitative RT-PCR and compared with the copper status in rat organs (liver, cerebellum, choroid plexus, and mammary gland), which differed in copper metabolism during development and differentiation. The CTR1 activity correlated with production of intracellular and extracellular cuproenzymes and deceased in nuclei of mesenchymal cells at high copper concentrations when copper metabolism followed the embryonic pattern. According to phylogenetic analysis, the most conserved regions of CTR1 are transmembrane domains (TMD) 2 and 3, which together contain seven amino acid residues capable of coordinating a copper atom. A model of the cuprophylic channel formed by TMD2 and TMD3 of the CTR1 homotrimer was proposed. In this model, copper is transported through the channel to the cytosolic C-terminal motif His-Cys-His. The ability of His-Cys-His to coordinate Cu(I) was evaluated by molecular modeling (MM+, ZINDO/1). Potential copper transfer from His-Cys-His to the Cys-X-X-Cys Cu (I) motif, present in all cytosol Cu-chaperones, was shown. The role of CTR1 as a donor and an acceptor of copper in higher eukaryotes is discussed.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.