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2.A.19.4.5
The K+-dependent Na+/Ca2+ exchanger, MCKX4 (has 40x higher affinity for K+ than NCKX2 due to a threonine to alanine substitution at position 551 in NCKX2 (Visser et al., 2007)). NCKX4 is highly expressed and regulates Ca2+ transport in ameloblasts during amelogenesis (the formation of tooth enamel). In fact, MCKX4 is critical for enamel maturation (Wang et al. 2014). Residues involved in Na+ binding have been identified (Altimimi et al. 2010).  Inhibitors of SLC26A4 that have shown promise in the treatment of different phenotypes of diseases including asthma (Guntupalli et al. 2024).

Accession Number:Q8NFF2
Protein Name:NCKX4
Length:605
Molecular Weight:66951.00
Species:Homo sapiens (Human) [9606]
Number of TMSs:11
Location1 / Topology2 / Orientation3: Membrane1 / Multi-pass membrane protein2
Substrate calcium(2+), sodium(1+), potassium(1+)

Cross database links:

RefSeq: NP_705932.1    NP_705933.1    NP_705934.1   
Entrez Gene ID: 123041   
Pfam: PF01699   
OMIM: 210750  phenotype
609840  gene
KEGG: hsa:123041    hsa:123041   

Gene Ontology

GO:0016021 C:integral to membrane
GO:0015297 F:antiporter activity
GO:0015293 F:symporter activity
GO:0006816 P:calcium ion transport
GO:0006813 P:potassium ion transport
GO:0006814 P:sodium ion transport
GO:0055085 P:transmembrane transport
GO:0005886 C:plasma membrane
GO:0006811 P:ion transport

References (11)

[1] “Molecular cloning of a fourth member of the potassium-dependent sodium-calcium exchanger gene family, NCKX4.”  Li X.-F.et.al.   12379639
[2] “Complete sequencing and characterization of 21,243 full-length human cDNAs.”  Ota T.et.al.   14702039
[3] “The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).”  The MGC Project Teamet.al.   15489334
[4] “The full-ORF clone resource of the German cDNA consortium.”  Bechtel S.et.al.   17974005
[5] “Genetic determinants of hair, eye and skin pigmentation in Europeans.”  Sulem P.et.al.   17952075
[6] “Molecular cloning of a fourth member of the potassium-dependent sodium-calcium exchanger gene family, NCKX4.”  Li X.-F.et.al.   12379639
[7] “Complete sequencing and characterization of 21,243 full-length human cDNAs.”  Ota T.et.al.   14702039
[8] “The DNA sequence and analysis of human chromosome 14.”  Heilig R.et.al.   12508121
[9] “The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).”  The MGC Project Teamet.al.   15489334
[10] “The full-ORF clone resource of the German cDNA consortium.”  Bechtel S.et.al.   17974005
[11] “Genetic determinants of hair, eye and skin pigmentation in Europeans.”  Sulem P.et.al.   17952075

External Searches:

Analyze:

Predict TMSs (Predict number of transmembrane segments)
Window Size: Angle:  
FASTA formatted sequence
1:	MLPQQVGFVC AVLALVCCAS GLFGSLGHKT ASASKRVLPD TWRNRKLMAP VNGTQTAKNC 
61:	TDPAIHEFPT DLFSNKERQH GAVLLHILGA LYMFYALAIV CDDFFVPSLE KICERLHLSE 
121:	DVAGATFMAA GSSTPELFAS VIGVFITHGD VGVGTIVGSA VFNILCIIGV CGLFAGQVVR 
181:	LTWWAVCRDS VYYTISVIVL IVFIYDEQIV WWEGLVLIIL YVFYILIMKY NVKMQAFFTV 
241:	KQKSIANGNP VNSELEAGND FYDGSYDDPS VPLLGQVKEK PQYGKNPVVM VDEIMSSSPP 
301:	KFTFPEAGLR IMITNKFGPR TRLRMASRII INERQRLINS ANGVSSKPLQ NGRHENIENG 
361:	NVPVENPEDP QQNQEQQPPP QPPPPEPEPV EADFLSPFSV PEARGDKVKW VFTWPLIFLL 
421:	CVTIPNCSKP RWEKFFMVTF ITATLWIAVF SYIMVWLVTI IGYTLGIPDV IMGITFLAAG 
481:	TSVPDCMASL IVARQGLGDM AVSNTIGSNV FDILVGLGVP WGLQTMVVNY GSTVKINSRG 
541:	LVYSVVLLLG SVALTVLGIH LNKWRLDRKL GVYVLVLYAI FLCFSIMIEF NVFTFVNLPM 
601:	CREDD