Incidental Mutation 'D4216:Slc34a2'
ID 237
Institutional Source Beutler Lab
Gene Symbol Slc34a2
Ensembl Gene ENSMUSG00000029188
Gene Name solute carrier family 34 (sodium phosphate), member 2
Synonyms D5Ertd227e, type IIb Na/Picotransporter, Npt2b, NaPi-2b
Accession Numbers

Genbank: NM_011402; MGI: 1342284

Is this an essential gene? Essential (E-score: 1.000) question?
Stock # D4216 (G3) of strain honey
Quality Score
Status Validated
Chromosome 5
Chromosomal Location 53038081-53071664 bp(+) (GRCm38)
Type of Mutation missense
DNA Base Change (assembly) A to G at 53065497 bp (GRCm38)
Zygosity Homozygous
Amino Acid Change Threonine to Alanine at position 310 (T310A)
Ref Sequence ENSEMBL: ENSMUSP00000092380 (fasta)
Gene Model predicted gene model for transcript(s): [ENSMUST00000094787] [ENSMUST00000170523]
AlphaFold Q9DBP0
Predicted Effect probably benign
Transcript: ENSMUST00000094787
AA Change: T310A

PolyPhen 2 Score 0.012 (Sensitivity: 0.96; Specificity: 0.78)
SMART Domains Protein: ENSMUSP00000092380
Gene: ENSMUSG00000029188
AA Change: T310A

Pfam:Na_Pi_cotrans 110 252 2.3e-26 PFAM
Pfam:Na_Pi_cotrans 374 551 2.6e-17 PFAM
low complexity region 553 570 N/A INTRINSIC
low complexity region 616 645 N/A INTRINSIC
low complexity region 649 655 N/A INTRINSIC
Predicted Effect noncoding transcript
Transcript: ENSMUST00000147243
Predicted Effect probably benign
Transcript: ENSMUST00000170523
SMART Domains Protein: ENSMUSP00000130692
Gene: ENSMUSG00000029188

Pfam:Na_Pi_cotrans 110 187 2.9e-20 PFAM
Meta Mutation Damage Score 0.1045 question?
Coding Region Coverage
  • 1x: 58.2%
  • 3x: 22.7%
Validation Efficiency 68% (27/40)
MGI Phenotype FUNCTION: [Summary is not available for the mouse gene. This summary is for the human ortholog.] The protein encoded by this gene is a pH-sensitive sodium-dependent phosphate transporter. Phosphate uptake is increased at lower pH. Defects in this gene are a cause of pulmonary alveolar microlithiasis. Three transcript variants encoding two different isoforms have been found for this gene. [provided by RefSeq, May 2010]
PHENOTYPE: Homozygous null mice display embryonic lethality, embryonic growth arrest, failure of embryo turning and somitogenesis, impaired placental development and impaired yolk sac vascular remodeling. [provided by MGI curators]
Allele List at MGI

All alleles(3) : Targeted, knock-out(1) Targeted, other(2)

Other mutations in this stock
Total: 9 list
GeneRefVarChr/LocMutationPredicted EffectZygosity
Fbxo33 A T 12: 59,206,050 V221E probably benign Het
Frmpd2 T A 14: 33,552,057 F1085L probably damaging Homo
Kcnrg T G 14: 61,611,793 Y234* probably null Homo
Mrgpra6 T A 7: 47,188,756 L231F probably damaging Het
Naca T C 10: 128,044,240 S1714P possibly damaging Homo
Rapgef6 T C 11: 54,668,746 probably benign Homo
Ric8b T C 10: 85,015,141 L546P probably damaging Het
Ssc5d C T 7: 4,943,983 T1112I possibly damaging Homo
Stau1 A G 2: 166,949,750 V489A probably benign Homo
Other mutations in Slc34a2
AlleleSourceChrCoordTypePredicted EffectPPH Score
IGL00785:Slc34a2 APN 5 53065608 missense probably benign 0.06
IGL00845:Slc34a2 APN 5 53058354 splice site probably benign
IGL01024:Slc34a2 APN 5 53067630 missense possibly damaging 0.61
IGL01300:Slc34a2 APN 5 53068127 critical splice acceptor site probably null
IGL01680:Slc34a2 APN 5 53060876 missense probably damaging 1.00
IGL02226:Slc34a2 APN 5 53067731 missense probably benign 0.12
IGL02682:Slc34a2 APN 5 53059238 missense possibly damaging 0.64
IGL03294:Slc34a2 APN 5 53063998 missense probably benign 0.00
tucumcari UTSW 5 53064009 missense possibly damaging 0.68
R0094:Slc34a2 UTSW 5 53063968 missense probably benign 0.28
R0227:Slc34a2 UTSW 5 53069626 missense possibly damaging 0.51
R0524:Slc34a2 UTSW 5 53064873 nonsense probably null
R0836:Slc34a2 UTSW 5 53067707 missense probably benign
R1525:Slc34a2 UTSW 5 53069506 missense probably benign 0.00
R1655:Slc34a2 UTSW 5 53069419 missense probably benign 0.00
R1753:Slc34a2 UTSW 5 53061391 missense probably benign 0.37
R1838:Slc34a2 UTSW 5 53058436 missense probably benign
R2361:Slc34a2 UTSW 5 53068145 missense probably benign 0.10
R2405:Slc34a2 UTSW 5 53058181 missense probably benign 0.04
R3688:Slc34a2 UTSW 5 53064832 missense probably benign 0.06
R4108:Slc34a2 UTSW 5 53064009 missense possibly damaging 0.68
R4176:Slc34a2 UTSW 5 53067568 missense probably damaging 1.00
R4380:Slc34a2 UTSW 5 53069286 missense probably damaging 1.00
R4464:Slc34a2 UTSW 5 53069182 missense probably damaging 0.99
R4780:Slc34a2 UTSW 5 53069451 missense probably damaging 1.00
R4816:Slc34a2 UTSW 5 53069020 missense probably damaging 1.00
R4934:Slc34a2 UTSW 5 53067600 missense probably damaging 1.00
R5265:Slc34a2 UTSW 5 53061434 missense probably damaging 0.96
R5309:Slc34a2 UTSW 5 53069488 missense probably damaging 0.96
R5313:Slc34a2 UTSW 5 53069339 missense probably damaging 0.96
R5884:Slc34a2 UTSW 5 53069380 missense possibly damaging 0.46
R6084:Slc34a2 UTSW 5 53067647 missense possibly damaging 0.91
R6310:Slc34a2 UTSW 5 53064797 critical splice acceptor site probably null
R6568:Slc34a2 UTSW 5 53069134 missense probably damaging 1.00
R6817:Slc34a2 UTSW 5 53064028 missense probably damaging 0.98
R6845:Slc34a2 UTSW 5 53069169 missense probably damaging 0.96
R6944:Slc34a2 UTSW 5 53064883 missense probably benign
R7873:Slc34a2 UTSW 5 53058372 missense probably benign 0.02
R8114:Slc34a2 UTSW 5 53068359 missense probably benign 0.00
R8158:Slc34a2 UTSW 5 53060840 missense probably damaging 1.00
R8364:Slc34a2 UTSW 5 53068374 missense possibly damaging 0.75
R9158:Slc34a2 UTSW 5 53063875 missense possibly damaging 0.95
R9235:Slc34a2 UTSW 5 53069325 missense probably benign 0.00
R9314:Slc34a2 UTSW 5 53060801 missense possibly damaging 0.61
Z1176:Slc34a2 UTSW 5 53060817 missense probably damaging 1.00
Nature of Mutation

DNA sequencing using the SOLiD technique identified an A to G transition at position 975 of the Slc34a2 transcript. Two transcripts of the Slc34a2 gene are displayed on Ensembl and Vega. The mutated nucleotide causes a threonine to alanine substitution at amino acid 310 of the encoded protein. The mutation has been confirmed by DNA sequencing using the Sanger method (Figure 1).

Protein Function and Prediction
The Slc34a2 gene encodes a 697 eight-pass membrane protein that is involved in actively transporting phosphate into cells via Na+ cotransport. Slc34a2 may be the main phosphate transport protein in the intestinal brush border membrane and may have a role in the synthesis of surfactant in lungs' alveoli. It is highly abundant in the ileum of the small intestine and upregulated in the entire small intestine by a low phosphate diet. It is also upregulated by metabolic acidosis (Uniprot Q9DBP0). Homozygous null mice display embryonic lethality, embryonic growth arrest, failure of embryo turning and somitogenesis, impaired placental development and impaired yolk sac vascular remodeling. In humans, homozgyous mutations in the SLC34A2 gene result in pulmonary alveolar microlithiasis (OMIM 265100), a disease characterized by the deposition of calcium phosphate microliths throughout the lungs.
The T310A change is located in the extracellular domain between transmembrane domains 3 and 4. The change is predicted to be benign by the PolyPhen program.
Posted On 2010-06-23