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Calx Na/Ca-exchange protein [ Drosophila melanogaster (fruit fly) ]

Gene ID: 42481, updated on 19-Nov-2025
Official Symbol
Calxprovided by FlyBase
Official Full Name
Na/Ca-exchange proteinprovided by FlyBase
Primary source
FLYBASE:FBgn0013995
Locus tag
Dmel_CG5685
See related
AllianceGenome:FB:FBgn0013995
Gene type
protein coding
RefSeq status
REVIEWED
Organism
Drosophila melanogaster
Lineage
Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Hexapoda; Insecta; Pterygota; Neoptera; Endopterygota; Diptera; Brachycera; Muscomorpha; Ephydroidea; Drosophilidae; Drosophila; Sophophora
Also known as
9C5; anon-93ABa; calx; calX; CalX; CALX; CALX1.1; CG5685; Dmel/Ncx; Dmel\CG5685; Ncx; NCX
Summary
Enables calcium ion binding activity and calcium:sodium antiporter activity. Involved in neuromuscular process controlling posture and phototransduction. Predicted to be located in membrane. Predicted to be active in axon; postsynapse; and sarcolemma. Is expressed in several structures, including adult brain; adult head; adult heart; anlage in statu nascendi; and sensory organ cell. Human ortholog(s) of this gene implicated in hypertension. Orthologous to human SLC8A1 (solute carrier family 8 member A1); SLC8A2 (solute carrier family 8 member A2); and SLC8A3 (solute carrier family 8 member A3). [provided by Alliance of Genome Resources, Jul 2025]
Orthologs
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See Calx in Genome Data Viewer
Location:
93A4-93B3; 3-70 cM
Exon count:
17
Annotation release Status Assembly Chr Location
Release 6.54 current Release 6 plus ISO1 MT (GCF_000001215.4) 3R NT_033777.3 (20978183..21015613)
Release 5.57 previous assembly Release 5 (GCF_000001215.2) 3R NT_033777.2 (16803905..16841335)

Chromosome 3R - NT_033777.3Genomic Context describing neighboring genes Neighboring gene uncharacterized protein Neighboring gene hadley Neighboring gene Na pump alpha subunit Neighboring gene uncharacterized protein Neighboring gene Alkaline phosphatase 5 Neighboring gene uncharacterized protein Neighboring gene Ral interacting protein

Go to nucleotide: Graphics FASTA GenBank

Related articles in PubMed

  1. Structure-function analysis of CALX1.1, a Na+-Ca2+ exchanger from Drosophila. Mutagenesis of ionic regulatory sites. Dyck C, et al. J Biol Chem, 1998 May 22. PMID 9582332
  2. Dynamic features of allosteric Ca2+ sensor in tissue-specific NCX variants. Giladi M, et al. Cell Calcium, 2012 Jun. PMID 22571864
  3. Model for the allosteric regulation of the Na+/Ca2+ exchanger NCX. Abiko LA, et al. Proteins, 2016 May. PMID 26850381
  4. Structural studies of the Ca(2+) regulatory domain of Drosophila Na(+)/Ca (2+) exchanger CALX. Zheng L, et al. Adv Exp Med Biol, 2013. PMID 23224870
  5. Crystal structure of CBD2 from the Drosophila Na(+)/Ca(2+) exchanger: diversity of Ca(2+) regulation and its alternative splicing modification. Wu M, et al. J Mol Biol, 2009 Mar 20. PMID 19361442

See all (106) citations in PubMed

GeneRIFs: Gene References Into Functions

What's a GeneRIF?
  1. CALX-CBD1 Ca(2+)-Binding Cooperativity Studied by NMR Spectroscopy and ITC with Bayesian Statistics.
    Title: CALX-CBD1 Ca(2+)-Binding Cooperativity Studied by NMR Spectroscopy and ITC with Bayesian Statistics.
  2. Structural studies of the Ca(2+) regulatory domain of Drosophila Na(+)/Ca (2+) exchanger CALX.
    Title: Structural studies of the Ca(2+) regulatory domain of Drosophila Na(+)/Ca (2+) exchanger CALX.
  3. Ca(2+) inhibition of CALX is achieved by interdomain conformational changes induced by Ca(2+) binding at the CBD1 regulatory domain.
    Title: Structural basis of the Ca2+ inhibitory mechanism of Drosophila Na+/Ca2+ exchanger CALX and its modification by alternative splicing.
  4. Ca(2+) binding only enhances the stability of the Ca(2+) binding site of CBD1 near the hinge region while the overall structure of CBD1 remains largely unaffected for calx
    Title: Crystal structures of progressive Ca2+ binding states of the Ca2+ sensor Ca2+ binding domain 1 (CBD1) from the CALX Na+/Ca2+ exchanger reveal incremental conformational transitions.
  5. results provide evidence that the diversity of Ca(2+) regulatory properties of NCX proteins can be achieved by (1) local structure rearrangement of Ca(2+) binding site to change Ca(2+) binding properties of CBD2 and (2) alternative splicing variation
    Title: Crystal structure of CBD2 from the Drosophila Na(+)/Ca(2+) exchanger: diversity of Ca(2+) regulation and its alternative splicing modification.
  6. Loss of CalX caused a transient response to light, an increase in signal amplification, and rapid adaptation. Conversely, overexpression of CalX suppressed the retinal degeneration caused by activity of the TRP channel.
    Title: Light activation, adaptation, and cell survival functions of the Na+/Ca2+ exchanger CalX.
Submit: New GeneRIF Correction
Products Interactant Other Gene Complex Source Pubs Description

Homology

Gene Ontology Provided by FlyBase

Function Evidence Code Pubs
enables antiporter activity IEA
Inferred from Electronic Annotation
more info
  
enables calcium ion binding IDA
Inferred from Direct Assay
more info
 PubMed 
enables calcium:sodium antiporter activity IBA
Inferred from Biological aspect of Ancestor
more info
  
enables calcium:sodium antiporter activity IDA
Inferred from Direct Assay
more info
 PubMed 
enables calcium:sodium antiporter activity IEA
Inferred from Electronic Annotation
more info
  
enables calcium:sodium antiporter activity IMP
Inferred from Mutant Phenotype
more info
 PubMed 
enables calcium:sodium antiporter activity TAS
Traceable Author Statement
more info
 PubMed 
enables calmodulin binding IEA
Inferred from Electronic Annotation
more info
  
enables metal ion binding IEA
Inferred from Electronic Annotation
more info
  
Process Evidence Code Pubs
involved_in calcium ion export across plasma membrane IBA
Inferred from Biological aspect of Ancestor
more info
  
involved_in calcium ion transport IEA
Inferred from Electronic Annotation
more info
  
involved_in cell communication IEA
Inferred from Electronic Annotation
more info
  
involved_in intracellular calcium ion homeostasis IBA
Inferred from Biological aspect of Ancestor
more info
  
involved_in monoatomic ion transport IEA
Inferred from Electronic Annotation
more info
  
involved_in neuromuscular process controlling posture IMP
Inferred from Mutant Phenotype
more info
 PubMed 
involved_in phototransduction IMP
Inferred from Mutant Phenotype
more info
 PubMed 
involved_in response to endoplasmic reticulum stress HMP PubMed 
involved_in sodium ion transmembrane transport IBA
Inferred from Biological aspect of Ancestor
more info
  
involved_in sodium ion transmembrane transport IEA
Inferred from Electronic Annotation
more info
  
involved_in sodium ion transport IEA
Inferred from Electronic Annotation
more info
  
involved_in transmembrane transport IEA
Inferred from Electronic Annotation
more info
  
Component Evidence Code Pubs
is_active_in axon IBA
Inferred from Biological aspect of Ancestor
more info
  
located_in membrane IEA
Inferred from Electronic Annotation
more info
  
located_in plasma membrane IEA
Inferred from Electronic Annotation
more info
  
is_active_in postsynapse IBA
Inferred from Biological aspect of Ancestor
more info
  
located_in rhabdomere membrane IEA
Inferred from Electronic Annotation
more info
  
is_active_in sarcolemma IBA
Inferred from Biological aspect of Ancestor
more info
  
Preferred Names
Na/Ca-exchange protein
Names
CG5685-PA
CG5685-PB
CG5685-PC
CG5685-PD
CG5685-PE
CG5685-PF
CG5685-PG
CG5685-PH
CG5685-PI
Calx-PA
Calx-PB
Calx-PC
Calx-PD
Calx-PE
Calx-PF
Calx-PG
Calx-PH
Calx-PI

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Genome Annotation

The following sections contain reference sequences that belong to a specific genome build. Explain

Reference assembly

Genomic

  1. NT_033777.3 Reference assembly

    Range
    20978183..21015613
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. NM_001260286.2 → NP_001247215.1  Na/Ca-exchange protein, isoform G

    See identical proteins and their annotated locations for NP_001247215.1

    Status: REVIEWED

    UniProtKB/TrEMBL
    A0A0B4K6E2, O18367
    Conserved Domains (4) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    TIGR00845
    Location:4 → 973
    caca; sodium/calcium exchanger 1
    pfam01699
    Location:800 → 965
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain

  2. NM_079699.4 → NP_524423.2  Na/Ca-exchange protein, isoform A

    See identical proteins and their annotated locations for NP_524423.2

    Status: REVIEWED

    UniProtKB/Swiss-Prot
    A0A0B4K6R7, Q24413, Q9VDG5
    UniProtKB/TrEMBL
    O18367
    Related
    FBpp0083402
    Conserved Domains (4) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    TIGR00845
    Location:4 → 950
    caca; sodium/calcium exchanger 1
    pfam01699
    Location:777 → 942
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain

  3. NM_001260285.2 → NP_001247214.1  Na/Ca-exchange protein, isoform F

    See identical proteins and their annotated locations for NP_001247214.1

    Status: REVIEWED

    UniProtKB/TrEMBL
    A0A0B4K6A6, O18367
    Conserved Domains (4) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    TIGR00845
    Location:4 → 960
    caca; sodium/calcium exchanger 1
    pfam01699
    Location:787 → 952
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain

  4. NM_169940.4 → NP_732576.1  Na/Ca-exchange protein, isoform B

    See identical proteins and their annotated locations for NP_732576.1

    Status: REVIEWED

    UniProtKB/Swiss-Prot
    A0A0B4K6R7, Q24413, Q9VDG5
    UniProtKB/TrEMBL
    O18367
    Related
    FBpp0083403
    Conserved Domains (4) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    TIGR00845
    Location:4 → 950
    caca; sodium/calcium exchanger 1
    pfam01699
    Location:777 → 942
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain

  5. NM_001260284.2 → NP_001247213.1  Na/Ca-exchange protein, isoform E

    See identical proteins and their annotated locations for NP_001247213.1

    Status: REVIEWED

    UniProtKB/TrEMBL
    A0A0B4K790, O18367
    Conserved Domains (4) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    TIGR00845
    Location:4 → 963
    caca; sodium/calcium exchanger 1
    pfam01699
    Location:790 → 955
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain

  6. NM_001300506.1 → NP_001287435.1  Na/Ca-exchange protein, isoform I

    See identical proteins and their annotated locations for NP_001287435.1

    Status: REVIEWED

    UniProtKB/TrEMBL
    A0A0B4LHD9
    Conserved Domains (3) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    pfam01699
    Location:126 → 297
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain

  7. NM_001300505.1 → NP_001287434.1  Na/Ca-exchange protein, isoform H

    See identical proteins and their annotated locations for NP_001287434.1

    Status: REVIEWED

    UniProtKB/TrEMBL
    A0A0B4LHD7, O18367
    Conserved Domains (4) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    TIGR00845
    Location:4 → 955
    caca; sodium/calcium exchanger 1
    pfam01699
    Location:782 → 947
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain

  8. NM_169941.2 → NP_732577.1  Na/Ca-exchange protein, isoform C

    See identical proteins and their annotated locations for NP_732577.1

    Status: REVIEWED

    UniProtKB/Swiss-Prot
    A0A0B4K6R7, Q24413, Q9VDG5
    UniProtKB/TrEMBL
    O18367
    Related
    FBpp0083404
    Conserved Domains (4) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    TIGR00845
    Location:4 → 950
    caca; sodium/calcium exchanger 1
    pfam01699
    Location:777 → 942
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain

  9. NM_001260283.2 → NP_001247212.1  Na/Ca-exchange protein, isoform D

    See identical proteins and their annotated locations for NP_001247212.1

    Status: REVIEWED

    UniProtKB/TrEMBL
    O18367
    Conserved Domains (4) summary
    smart00237
    Location:441 → 529
    Calx_beta; Domains in Na-Ca exchangers and integrin-beta4
    TIGR00845
    Location:4 → 950
    caca; sodium/calcium exchanger 1
    pfam01699
    Location:777 → 942
    Na_Ca_ex; Sodium/calcium exchanger protein
    pfam16494
    Location:300 → 414
    Na_Ca_ex_C; C-terminal extension of sodium/calcium exchanger domain
Nucleotide Protein
Heading Accession and Version
Protein Accession Links
GenPept Link UniProtKB Link
A0A0B4K6A6 A0A0B4K6A6
A0A0B4K6E2 A0A0B4K6E2
A0A0B4K6R7 A0A0B4K6R7
A0A0B4K790 A0A0B4K790
A0A0B4LHD7 A0A0B4LHD7
A0A0B4LHD9 A0A0B4LHD9
O18367 O18367
Q24413 Q24413
Q9VDG5 Q9VDG5
Q9VDG5.1

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