Seroatlas · Human Serome Atlas

BTN1A1

Butyrophilin subfamily 1 member A1

Also known as: BT, BT1A1_HUMAN, BTN, BTN1

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

Protein identityUniProt · HPA

UniProt accession
Q13410
Gene
BTN1A1
Ensembl
ENSG00000124557
Chromosome
6
Canonical length
526 aa
Protein class
Predicted membrane proteins
Secretome location
Intracellular and membrane

OverviewNCBI Gene

Butyrophilin is the major protein associated with fat droplets in the milk. It is a member of the immunoglobulin superfamily. It may have a cell surface receptor function. The human butyrophilin gene is localized in the major histocompatibility complex (MHC) class I region of 6p and may have arisen relatively recently in evolution by the shuffling of exons between 2 ancestral gene families [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

526 residues, UniProt reviewed canonical sequence.

>Q13410|BTN1A1
     1  MAVFPSSGLP RCLLTLILLQ LPKLDSAPFD VIGPPEPILA VVGEDAELPC RLSPNASAEH
    61  LELRWFRKKV SPAVLVHRDG REQEAEQMPE YRGRATLVQD GIAKGRVALR IRGVRVSDDG
   121  EYTCFFREDG SYEEALVHLK VAALGSDPHI SMQVQENGEI CLECTSVGWY PEPQVQWRTS
   181  KGEKFPSTSE SRNPDEEGLF TVAASVIIRD TSAKNVSCYI QNLLLGQEKK VEISIPASSL
   241  PRLTPWIVAV AVILMVLGLL TIGSIFFTWR LYNERPRERR NEFSSKERLL EELKWKKATL
   301  HAVDVTLDPD TAHPHLFLYE DSKSVRLEDS RQKLPEKTER FDSWPCVLGR ETFTSGRHYW
   361  EVEVGDRTDW AIGVCRENVM KKGFDPMTPE NGFWAVELYG NGYWALTPLR TPLPLAGPPR
   421  RVGIFLDYES GDISFYNMND GSDIYTFSNV TFSGPLRPFF CLWSSGKKPL TICPIADGPE
   481  RVTVIANAQD LSKEIPLSPM GEDSAPRDAD TLHSKLIPTQ PSQGAP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against BTN1A1 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
Secreted
Secreted
Yes
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.35
Highest tissue expression
30 nTPM

Expression across tissuesHPA

Tissue

  • breast: 30 nTPM
  • tonsil: 0.7 nTPM
  • lymph node: 0.5 nTPM
  • appendix: 0.3 nTPM
  • spleen: 0.3 nTPM
  • spinal cord: 0.2 nTPM

Single-cell type

  • breast lactating cells: 1,363 nCPM
  • cytotrophoblasts: 3.4 nCPM
  • thymocytes: 3.4 nCPM
  • early primary spermatocytes: 3 nCPM
  • breast secretory cells: 2.6 nCPM
  • epicardial cells: 2.3 nCPM

Immune cell

  • memory B-cell: 2.2 nTPM
  • naive B-cell: 1.9 nTPM
  • non-classical monocyte: 0.6 nTPM
  • eosinophil: 0.3 nTPM
  • MAIT T-cell: 0.2 nTPM
  • basophil: 0 nTPM

Brain region

  • hippocampal formation: 0.8 nTPM
  • cerebellum: 0.7 nTPM
  • medulla oblongata: 0.7 nTPM
  • midbrain: 0.6 nTPM
  • spinal cord: 0.6 nTPM
  • white matter: 0.6 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)
1.09
gnomAD pLI
0
gnomAD missense Z
1.32
DepMap mean gene effect
0.08
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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

InteractionsUniProt · HPA

Protein binding partners of BTN1A1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads BTN1A1 as an antibody target. Whether an autoantibody or antibody against BTN1A1 could matter depends on whether native BTN1A1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

BTN1A1 is annotated as secreted, so native BTN1A1 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label BTN1A1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/BTN1A1. 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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