Seroatlas · Human Serome Atlas

PTK2B

Protein-tyrosine kinase 2-beta

Also known as: CADTK, CAKB, FAK2, FAK2_HUMAN, PTK, PYK2, RAFTK

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

Protein identityUniProt · HPA

UniProt accession
Q14289
Gene
PTK2B
Ensembl
ENSG00000120899
Chromosome
8
Canonical length
1009 aa
Protein class
Disease related genes, Enzymes, Plasma proteins, Potential drug targets, Predicted intracellular proteins
Subcellular location
Plasma membrane,Cytosol
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene encodes a cytoplasmic protein tyrosine kinase which is involved in calcium-induced regulation of ion channels and activation of the map kinase signaling pathway. The encoded protein may represent an important signaling intermediate between neuropeptide-activated receptors or neurotransmitters that increase calcium flux and the downstream signals that regulate neuronal activity. The encoded protein undergoes rapid tyrosine phosphorylation and activation in response to increases in the intracellular calcium concentration, nicotinic acetylcholine receptor activation, membrane depolarization, or protein kinase C activation. This protein has been shown to bind CRK-associated substrate, nephrocystin, GTPase regulator associated with FAK, and the SH2 domain of GRB2. The encoded protein is a member of the FAK subfamily of protein tyrosine kinases but lacks significant sequence similarity to kinases from other subfamilies. Four transcript variants encoding two different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

1009 residues, UniProt reviewed canonical sequence.

>Q14289|PTK2B
     1  MSGVSEPLSR VKLGTLRRPE GPAEPMVVVP VDVEKEDVRI LKVCFYSNSF NPGKNFKLVK
    61  CTVQTEIREI ITSILLSGRI GPNIRLAECY GLRLKHMKSD EIHWLHPQMT VGEVQDKYEC
   121  LHVEAEWRYD LQIRYLPEDF MESLKEDRTT LLYFYQQLRN DYMQRYASKV SEGMALQLGC
   181  LELRRFFKDM PHNALDKKSN FELLEKEVGL DLFFPKQMQE NLKPKQFRKM IQQTFQQYAS
   241  LREEECVMKF FNTLAGFANI DQETYRCELI QGWNITVDLV IGPKGIRQLT SQDAKPTCLA
   301  EFKQIRSIRC LPLEEGQAVL QLGIEGAPQA LSIKTSSLAE AENMADLIDG YCRLQGEHQG
   361  SLIIHPRKDG EKRNSLPQIP MLNLEARRSH LSESCSIESD IYAEIPDETL RRPGGPQYGI
   421  AREDVVLNRI LGEGFFGEVY EGVYTNHKGE KINVAVKTCK KDCTLDNKEK FMSEAVIMKN
   481  LDHPHIVKLI GIIEEEPTWI IMELYPYGEL GHYLERNKNS LKVLTLVLYS LQICKAMAYL
   541  ESINCVHRDI AVRNILVASP ECVKLGDFGL SRYIEDEDYY KASVTRLPIK WMSPESINFR
   601  RFTTASDVWM FAVCMWEILS FGKQPFFWLE NKDVIGVLEK GDRLPKPDLC PPVLYTLMTR
   661  CWDYDPSDRP RFTELVCSLS DVYQMEKDIA MEQERNARYR TPKILEPTAF QEPPPKPSRP
   721  KYRPPPQTNL LAPKLQFQVP EGLCASSPTL TSPMEYPSPV NSLHTPPLHR HNVFKRHSMR
   781  EEDFIQPSSR EEAQQLWEAE KVKMRQILDK QQKQMVEDYQ WLRQEEKSLD PMVYMNDKSP
   841  LTPEKEVGYL EFTGPPQKPP RLGAQSIQPT ANLDRTDDLV YLNVMELVRA VLELKNELCQ
   901  LPPEGYVVVV KNVGLTLRKL IGSVDDLLPS LPSSSRTEIE GTQKLLNKDL AELINKMRLA
   961  QQNAVTSLSE ECKRQMLTAS HTLAVDAKNL LDAVDQAKVL ANLAHPPAE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PTK2B 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)
0.36
Highest tissue expression
137 nTPM

Expression across tissuesHPA

Tissue

  • cerebellum: 137 nTPM
  • bone marrow: 100 nTPM
  • cerebral cortex: 98 nTPM
  • hippocampal formation: 85 nTPM
  • thymus: 80 nTPM
  • spleen: 74 nTPM

Single-cell type

  • neutrophils: 1,388 nCPM
  • neutrophil progenitors: 772 nCPM
  • monocytes: 590 nCPM
  • monocyte progenitors: 406 nCPM
  • b-cells: 281 nCPM
  • plasma cells: 275 nCPM

Immune cell

  • non-classical monocyte: 54 nTPM
  • total PBMC: 50 nTPM
  • classical monocyte: 49 nTPM
  • basophil: 47 nTPM
  • naive B-cell: 47 nTPM
  • memory B-cell: 46 nTPM

Brain region

  • cerebral cortex: 268 nTPM
  • hippocampal formation: 255 nTPM
  • basal ganglia: 167 nTPM
  • amygdala: 151 nTPM
  • choroid plexus: 136 nTPM
  • white matter: 128 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)
0.31
gnomAD pLI
0.94
gnomAD missense Z
1.5
DepMap mean gene effect
0.13
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 1% 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 PTK2B 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 PTK2B as an antibody target. Whether an autoantibody or antibody against PTK2B could matter depends on whether native PTK2B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PTK2B is annotated at the cell surface, where native PTK2B 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 PTK2B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PTK2B. 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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