Seroatlas · Human Serome Atlas

ATP8B3

Phospholipid-transporting ATPase IK

Also known as: AT8B3_HUMAN, ATPIK

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
O60423
Gene
ATP8B3
Ensembl
ENSG00000130270
Chromosome
19
Canonical length
1300 aa
Protein class
Enzymes, Predicted membrane proteins

OverviewNCBI Gene

The protein encoded by this gene belongs to the family of P-type cation transport ATPases, and to the subfamily of aminophospholipid-transporting ATPases. The aminophospholipid translocases transport phosphatidylserine and phosphatidylethanolamine from one side of a bilayer to the other. This gene encodes member 3 of phospholipid-transporting ATPase 8B; other members of this protein family are located on chromosomes 1, 15 and 18. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

Canonical amino-acid sequenceUniProt

1300 residues, UniProt reviewed canonical sequence.

>O60423|ATP8B3
     1  MGTGPAQTPR STRAGPEPSP APPGPGDTGD SDVTQEGSGP AGIRGGETVI RAGMGDSPGR
    61  GAPERRHKAQ PGRARKYEWR PEGPTSMGSL GQREDLQDED RNSAFTWKVQ ANNRAYNGQF
   121  KEKVILCWQR KKYKTNVIRT AKYNFYSFLP LNLYEQFHRV SNLFFLIIII LQSIPDISTL
   181  PWFSLSTPMV CLLFIRATRD LVDDMGRHKS DRAINNRPCQ ILMGKSFKQK KWQDLCVGDV
   241  VCLRKDNIVP ADMLLLASTE PSSLCYVETV DIDGETNLKF RQALMVTHKE LATIKKMASF
   301  QGTVTCEAPN SRMHHFVGCL EWNDKKYSLD IGNLLLRGCR IRNTDTCYGL VIYAGFDTKI
   361  MKNCGKIHLK RTKLDLLMNK LVVVIFISVV LVCLVLAFGF GFSVKEFKDH HYYLSGVHGS
   421  SVAAESFFVF WSFLILLSVT IPMSMFILSE FIYLGNSVFI DWDVQMYYKP QDVPAKARST
   481  SLNDHLGQVE YIFSDKTGTL TQNILTFNKC CISGRVYGPD SEATTRPKEN PYLWNKFADG
   541  KLLFHNAALL HLVRTNGDEA VREFWRLLAI CHTVMVRESP RERPDQLLYQ AASPDEGALV
   601  TAARNFGYVF LSRTQDTVTI MELGEERVYQ VLAIMDFNST RKRMSVLVRK PEGAICLYTK
   661  GADTVIFERL HRRGAMEFAT EEALAAFAQE TLRTLCLAYR EVAEDIYEDW QQRHQEASLL
   721  LQNRAQALQQ LLGATAIEDR LQDGVPETIK CLKKSNIKIW VLTGDKQETA VNIGFACELL
   781  SENMLILEEK EISRILETYW ENSNNLLTRE SLSQVKLALV INGDFLDKLL VSLRKEPRAL
   841  AQNVNMDEAW QELGQSRRDF LYARRLSLLC RRFGLPLAAP PAQDSRARRS SEVLQERAFV
   901  DLASKCQAVI CCRVTPKQKA LIVALVKKYH QVVTLAIGDG ANDINMIKTA DVGVGLAGQE
   961  GMQAVQNSDF VLGQFCFLQR LLLVHGRWSY VRICKFLRYF FYKSMASMMV QVWFACYNGF
  1021  TGQPLYEGWF LALFNLLYST LPVLYIGLFE QDVSAEQSLE KPELYVVGQK DELFNYWVFV
  1081  QAIAHGVTTS LVNFFMTLWI SRDTAGPASF SDHQSFAVVV ALSCLLSITM EVILIIKYWT
  1141  ALCVATILLS LGFYAIMTTT TQSFWLFRVS PTTFPFLYAD LSVMSSPSIL LVVLLSVSIN
  1201  TFPVLALRVI FPALKELRAK EEKVEEGPSE EIFTMEPLPH VHRESRARRS SYAFSHREGY
  1261  ANLITQGTIL RRGPGVSSDI ASESLDPSDE EAASSPKESQ

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ATP8B3 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
10
Mean surface accessibility (rSASA)
0.31
Highest tissue expression
21 nTPM

Expression across tissuesHPA

Tissue

  • testis: 21 nTPM
  • bone marrow: 5.5 nTPM
  • spleen: 3.2 nTPM
  • thymus: 2.1 nTPM
  • adrenal gland: 1.7 nTPM
  • endometrium: 1.1 nTPM

Single-cell type

  • late primary spermatocytes: 32 nCPM
  • late spermatids: 22 nCPM
  • monocyte progenitors: 19 nCPM
  • early primary spermatocytes: 15 nCPM
  • neutrophil progenitors: 11 nCPM
  • early spermatids: 10 nCPM

Immune cell

  • intermediate monocyte: 3 nTPM
  • T-reg: 1.3 nTPM
  • NK-cell: 1.1 nTPM
  • classical monocyte: 0.9 nTPM
  • non-classical monocyte: 0.9 nTPM
  • eosinophil: 0.8 nTPM

Brain region

  • pons: 0.6 nTPM
  • thalamus: 0.6 nTPM
  • hypothalamus: 0.5 nTPM
  • medulla oblongata: 0.5 nTPM
  • amygdala: 0.4 nTPM
  • midbrain: 0.3 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.01
gnomAD pLI
0
gnomAD missense Z
-0.3
DepMap mean gene effect
-0.06
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads ATP8B3 as an antibody target. Whether an autoantibody or antibody against ATP8B3 could matter depends on whether native ATP8B3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ATP8B3 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label ATP8B3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ATP8B3. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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