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Vol 46(2012) N 2 p. 304-315; A.N. Skvortsov1,2*, E.A. Zatulovskiy1, L.V. Puchkova1 Structure-Functional Organization of Eukaryotic High-Affinity Copper Importer CTR1 Determines Its Ability to Transport Copper, Silver, and Cisplatin 1St-Petersburg State Polytechnic University St-Petersburg, St-Petersburg, 195251 Russia2Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064 Russia *colbug@mail.ru Received - 2011-04-26; Accepted - 2011-08-03 It was shown recently, that high affinity Cu(I) importer eukaryotic protein CTR1 can also transport in vitro abiogenic Ag(I) ions and anticancer drug cisplatin. At present, there is no rational explanation how CTR1 can transfer platinum group which is different by coordination properties from highly similar Cu(I) and Ag(I). To understand the phenomenon, we analyzed 25 sequences of chordate CTR1 proteins and found out the conserved patterns of organization of N-terminal extracellular part of CTR1 which is responsible for initial metal binding. Extracellular copper-binding motifs were qualified by their coordination properties. It was shown that the relative position of methionine- and histidine-rich copper-binding motifs predisposes the extra- cellular CTR1 region to binding of copper, silver, and cisplatin. Relation between the tissue-specific expression of the CTR1 gene, steady-state copper concentration, and silver and platinum accumulation in organs of mice in vivo were analyzed. Significant positive yet incomplete correlation was found to exist between these variables. Basing on structural and functional peculiarities of N-terminal part of CTR1 a hypothesis of coupled transport of copper and cisplatin has been suggested which avoids disagreement between CTR1-mediated cisplatin transport in vitro and irreversible binding of platinum to Met-rich peptides. CTR1, copper metabolism, silver transport, cisplatin, molecular evolution, correlation analysis |