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Calx, a Na-Ca exchanger gene of Drosophila melanogaster.

ABSTRACT: We have cloned Calx, a gene that encodes a Na-Ca exchanger of Drosophila melanogaster. Calx encodes two repeated motifs, Calx-alpha and Calx-beta, that overlap domains required for exchanger activity and regulation. Calx has multiple transcripts in adults, including at least one expressed in the retina. The Calx genomic locus comprises >/=35 kb between the Atpalpha and rudimentary-like genes in chromosomal region 93B. In Xenopus oocytes, microinjected Calx cRNA induces calcium uptake like that of its homolog, the 3Na+-1Ca2+ exchanger of mammalian heart. Implications of Calx-alpha motifs for the mechanism of Na-Ca exchange are discussed.

SUBMITTER: Schwarz EM

PROVIDER: S-EPMC23348 | biostudies-literature | 1997 Sep

REPOSITORIES: biostudies-literature

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Calx, a Na-Ca exchanger gene of Drosophila melanogaster.

Schwarz E M EM Benzer S S

Proceedings of the National Academy of Sciences of the United States of America 19970901 19

We have cloned Calx, a gene that encodes a Na-Ca exchanger of Drosophila melanogaster. Calx encodes two repeated motifs, Calx-alpha and Calx-beta, that overlap domains required for exchanger activity and regulation. Calx has multiple transcripts in adults, including at least one expressed in the retina. The Calx genomic locus comprises >/=35 kb between the Atpalpha and rudimentary-like genes in chromosomal region 93B. In Xenopus oocytes, microinjected Calx cRNA induces calcium uptake like that o ...[more]

PMID: 9294196

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