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Scallop DMT functions as a Ca2+ transporter.

Haruhiko Toyohara·Sayuri Yamamoto·Masatomi Hosoi·Masaya Takagi·Isao Hayashi·Kenji Nakao·Shuji Kaneko
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Abstract

We identified a DMT (divalent metal transporter) homologous protein that functions as a Ca(2+) transporter. Scallop DMT cDNA encodes a 539-amino-acid protein with 12 putative membrane-spanning domains and has a consensus transport motif in the fourth extracellular loop. Since its mRNA is significantly expressed in the gill and intestine, it is assumed that scallop DMT transports Ca(2+) from seawater by the gill and from food by the intestine. Scallop DMT lacks the iron-responsive element commonly found in iron-regulatory proteins, suggesting that it is free of the post-transcriptional regulation from intracellular Fe(2+) concentration. Scallop DMT distinctly functions as a Ca(2+) transporter unlike other DMTs, however, it also transports Fe(2+) and Cd(2+) similar to them.

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Amino Acid MotifsAmino Acid SequenceAnimalsBiological TransportCadmiumCalciumCation Transport ProteinsCloning, MolecularConsensus SequenceDNA, ComplementaryFemaleGene ExpressionIronMicroinjectionsMolecular Sequence DataMolluscaOocytesPatch-Clamp TechniquesPolymerase Chain ReactionProtein Structure, SecondaryProtein Structure, TertiaryRNA, MessengerReverse Transcriptase Polymerase Chain ReactionSequence Analysis, DNASequence Homology, Amino AcidTissue DistributionXenopusJournal ArticleResearch Support, Non-U.S. Gov't

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Haruhiko Toyohara, Sayuri Yamamoto, Masatomi Hosoi, Masaya Takagi, Isao Hayashi, Kenji Nakao, Shuji Kaneko. 2005-04-09. Scallop DMT functions as a Ca2+ transporter.. https://doi.org/10.1016/j.febslet.2005.03.082

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