Seroatlas · Human Serome Atlas

BTK

Tyrosine-protein kinase BTK

Also known as: AGMX1, ATK, BTK_HUMAN, IMD1, PSCTK1, XLA

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

Protein identityUniProt · HPA

UniProt accession
Q06187
Gene
BTK
Ensembl
ENSG00000010671
Chromosome
X
Canonical length
659 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, FDA approved drug targets, Human disease related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location
Plasma membrane,Cytosol

OverviewNCBI Gene

The protein encoded by this gene plays a crucial role in B-cell development. Mutations in this gene cause X-linked agammaglobulinemia type 1, which is an immunodeficiency characterized by the failure to produce mature B lymphocytes, and associated with a failure of Ig heavy chain rearrangement. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Dec 2013]

Canonical amino-acid sequenceUniProt

659 residues, UniProt reviewed canonical sequence.

>Q06187|BTK
     1  MAAVILESIF LKRSQQKKKT SPLNFKKRLF LLTVHKLSYY EYDFERGRRG SKKGSIDVEK
    61  ITCVETVVPE KNPPPERQIP RRGEESSEME QISIIERFPY PFQVVYDEGP LYVFSPTEEL
   121  RKRWIHQLKN VIRYNSDLVQ KYHPCFWIDG QYLCCSQTAK NAMGCQILEN RNGSLKPGSS
   181  HRKTKKPLPP TPEEDQILKK PLPPEPAAAP VSTSELKKVV ALYDYMPMNA NDLQLRKGDE
   241  YFILEESNLP WWRARDKNGQ EGYIPSNYVT EAEDSIEMYE WYSKHMTRSQ AEQLLKQEGK
   301  EGGFIVRDSS KAGKYTVSVF AKSTGDPQGV IRHYVVCSTP QSQYYLAEKH LFSTIPELIN
   361  YHQHNSAGLI SRLKYPVSQQ NKNAPSTAGL GYGSWEIDPK DLTFLKELGT GQFGVVKYGK
   421  WRGQYDVAIK MIKEGSMSED EFIEEAKVMM NLSHEKLVQL YGVCTKQRPI FIITEYMANG
   481  CLLNYLREMR HRFQTQQLLE MCKDVCEAME YLESKQFLHR DLAARNCLVN DQGVVKVSDF
   541  GLSRYVLDDE YTSSVGSKFP VRWSPPEVLM YSKFSSKSDI WAFGVLMWEI YSLGKMPYER
   601  FTNSETAEHI AQGLRLYRPH LASEKVYTIM YSCWHEKADE RPTFKILLSN ILDVMDEES

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against BTK 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
0
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
63 nTPM

Expression across tissuesHPA

Tissue

  • tonsil: 63 nTPM
  • lymph node: 42 nTPM
  • spleen: 36 nTPM
  • bone marrow: 24 nTPM
  • appendix: 23 nTPM
  • lung: 16 nTPM

Single-cell type

  • megakaryocytes: 309 nCPM
  • platelets: 273 nCPM
  • mast cells: 158 nCPM
  • megakaryocyte progenitors: 90 nCPM
  • b-cells: 81 nCPM
  • pdcs: 80 nCPM

Immune cell

  • basophil: 515 nTPM
  • non-classical monocyte: 119 nTPM
  • eosinophil: 107 nTPM
  • intermediate monocyte: 95 nTPM
  • myeloid DC: 70 nTPM
  • naive B-cell: 69 nTPM

Brain region

  • white matter: 7.4 nTPM
  • medulla oblongata: 4.6 nTPM
  • thalamus: 4.2 nTPM
  • spinal cord: 3.1 nTPM
  • midbrain: 3 nTPM
  • pons: 3 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about BTK.

Disease | AllUniProt

Conditions BTK is implicated in, by any mechanism.

  • X-linked agammaglobulinemia (XLA) MIM:300755
  • Growth hormone deficiency, isolated, 3, with agammaglobulinemia (IGHD3) MIM:307200

Disease | GeneticClinVar

349 pathogenic / likely-pathogenic of 950 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.1
gnomAD pLI
1
gnomAD missense Z
4.04
DepMap mean gene effect
0.03
DepMap dependency class
selective

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

BTK is annotated at the cell surface, where native BTK 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 BTK as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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