Seroatlas · Human Serome Atlas

BTN2A2

Butyrophilin subfamily 2 member A2

Also known as: BT2.2, BT2A2_HUMAN, BTF2, BTN2.2

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

Protein identityUniProt · HPA

UniProt accession
Q8WVV5
Gene
BTN2A2
Ensembl
ENSG00000124508
Chromosome
6
Canonical length
523 aa
Protein class
Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Mitochondria

OverviewNCBI Gene

Butyrophilin is the major protein associated with fat droplets in the milk. This gene is a member of the BTN2 subfamily of genes, which encode proteins belonging to the butyrophilin protein family. The gene is located in a cluster on chromosome 6, consisting of seven genes belonging to the expanding B7/butyrophilin-like group, a subset of the immunoglobulin gene superfamily. The encoded protein is a type I receptor glycoprotein involved in lipid, fatty-acid and sterol metabolism. Several alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2010]

Canonical amino-acid sequenceUniProt

523 residues, UniProt reviewed canonical sequence.

>Q8WVV5|BTN2A2
     1  MEPAAALHFS LPASLLLLLL LLLLSLCALV SAQFTVVGPA NPILAMVGEN TTLRCHLSPE
    61  KNAEDMEVRW FRSQFSPAVF VYKGGRERTE EQMEEYRGRI TFVSKDINRG SVALVIHNVT
   121  AQENGIYRCY FQEGRSYDEA ILRLVVAGLG SKPLIEIKAQ EDGSIWLECI SGGWYPEPLT
   181  VWRDPYGEVV PALKEVSIAD ADGLFMVTTA VIIRDKYVRN VSCSVNNTLL GQEKETVIFI
   241  PESFMPSASP WMVALAVILT ASPWMVSMTV ILAVFIIFMA VSICCIKKLQ REKKILSGEK
   301  KVEQEEKEIA QQLQEELRWR RTFLHAADVV LDPDTAHPEL FLSEDRRSVR RGPYRQRVPD
   361  NPERFDSQPC VLGWESFASG KHYWEVEVEN VMVWTVGVCR HSVERKGEVL LIPQNGFWTL
   421  EMFGNQYRAL SSPERILPLK ESLCRVGVFL DYEAGDVSFY NMRDRSHIYT CPRSAFTVPV
   481  RPFFRLGSDD SPIFICPALT GASGVMVPEE GLKLHRVGTH QSL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against BTN2A2 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
Cell surface
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.34
Highest tissue expression
34 nTPM

Expression across tissuesHPA

Tissue

  • tonsil: 34 nTPM
  • lymph node: 30 nTPM
  • choroid plexus: 28 nTPM
  • appendix: 21 nTPM
  • spleen: 21 nTPM
  • cerebellum: 18 nTPM

Single-cell type

  • mast cells: 58 nCPM
  • cdc: 44 nCPM
  • plasma cells: 44 nCPM
  • b-cells: 33 nCPM
  • choroid plexus epithelial cells: 27 nCPM
  • kupffer cells: 23 nCPM

Immune cell

  • naive B-cell: 30 nTPM
  • memory B-cell: 24 nTPM
  • myeloid DC: 24 nTPM
  • intermediate monocyte: 15 nTPM
  • classical monocyte: 14 nTPM
  • neutrophil: 12 nTPM

Brain region

  • choroid plexus: 41 nTPM
  • cerebellum: 26 nTPM
  • pons: 13 nTPM
  • medulla oblongata: 12 nTPM
  • midbrain: 11 nTPM
  • white matter: 11 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)
1.21
gnomAD pLI
0
gnomAD missense Z
-0.04
DepMap mean gene effect
0.13
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 BTN2A2 as an antibody target. Whether an autoantibody or antibody against BTN2A2 could matter depends on whether native BTN2A2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

BTN2A2 is annotated at the cell surface, where native BTN2A2 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label BTN2A2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/BTN2A2. 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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