Seroatlas · Human Serome Atlas

PTK2

Focal adhesion kinase 1

Also known as: FADK, FAK, FAK1, FAK1_HUMAN, PPP1R71

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

Protein identityUniProt · HPA

UniProt accession
Q05397
Gene
PTK2
Ensembl
ENSG00000169398
Chromosome
8
Canonical length
1052 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, Plasma proteins, Potential drug targets, Predicted intracellular proteins
Subcellular location
Vesicles,Focal adhesion sites,Primary cilium,Primary cilium tip,Cytosol

OverviewNCBI Gene

This gene encodes a cytoplasmic protein tyrosine kinase which is found concentrated in the focal adhesions that form between cells growing in the presence of extracellular matrix constituents. The encoded protein is a member of the FAK subfamily of protein tyrosine kinases but lacks significant sequence similarity to kinases from other subfamilies. Activation of this gene may be an important early step in cell growth and intracellular signal transduction pathways triggered in response to certain neural peptides or to cell interactions with the extracellular matrix. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2017]

Canonical amino-acid sequenceUniProt

1052 residues, UniProt reviewed canonical sequence.

>Q05397|PTK2
     1  MAAAYLDPNL NHTPNSSTKT HLGTGMERSP GAMERVLKVF HYFESNSEPT TWASIIRHGD
    61  ATDVRGIIQK IVDSHKVKHV ACYGFRLSHL RSEEVHWLHV DMGVSSVREK YELAHPPEEW
   121  KYELRIRYLP KGFLNQFTED KPTLNFFYQQ VKSDYMLEIA DQVDQEIALK LGCLEIRRSY
   181  WEMRGNALEK KSNYEVLEKD VGLKRFFPKS LLDSVKAKTL RKLIQQTFRQ FANLNREESI
   241  LKFFEILSPV YRFDKECFKC ALGSSWIISV ELAIGPEEGI SYLTDKGCNP THLADFTQVQ
   301  TIQYSNSEDK DRKGMLQLKI AGAPEPLTVT APSLTIAENM ADLIDGYCRL VNGTSQSFII
   361  RPQKEGERAL PSIPKLANSE KQGMRTHAVS VSETDDYAEI IDEEDTYTMP STRDYEIQRE
   421  RIELGRCIGE GQFGDVHQGI YMSPENPALA VAIKTCKNCT SDSVREKFLQ EALTMRQFDH
   481  PHIVKLIGVI TENPVWIIME LCTLGELRSF LQVRKYSLDL ASLILYAYQL STALAYLESK
   541  RFVHRDIAAR NVLVSSNDCV KLGDFGLSRY MEDSTYYKAS KGKLPIKWMA PESINFRRFT
   601  SASDVWMFGV CMWEILMHGV KPFQGVKNND VIGRIENGER LPMPPNCPPT LYSLMTKCWA
   661  YDPSRRPRFT ELKAQLSTIL EEEKAQQEER MRMESRRQAT VSWDSGGSDE APPKPSRPGY
   721  PSPRSSEGFY PSPQHMVQTN HYQVSGYPGS HGITAMAGSI YPGQASLLDQ TDSWNHRPQE
   781  IAMWQPNVED STVLDLRGIG QVLPTHLMEE RLIRQQQEME EDQRWLEKEE RFLKPDVRLS
   841  RGSIDREDGS LQGPIGNQHI YQPVGKPDPA APPKKPPRPG APGHLGSLAS LSSPADSYNE
   901  GVKLQPQEIS PPPTANLDRS NDKVYENVTG LVKAVIEMSS KIQPAPPEEY VPMVKEVGLA
   961  LRTLLATVDE TIPLLPASTH REIEMAQKLL NSDLGELINK MKLAQQYVMT SLQQEYKKQM
  1021  LTAAHALAVD AKNLLDVIDQ ARLKMLGQTR PH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PTK2 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)
0.37
Highest tissue expression
110 nTPM

Expression across tissuesHPA

Tissue

  • blood vessel: 110 nTPM
  • hippocampal formation: 76 nTPM
  • spinal cord: 75 nTPM
  • placenta: 70 nTPM
  • midbrain: 68 nTPM
  • basal ganglia: 67 nTPM

Single-cell type

  • oligodendrocytes: 1,292 nCPM
  • sertoli cells: 1,032 nCPM
  • urothelial cells: 750 nCPM
  • renal collecting duct principal cells: 733 nCPM
  • renal connecting tubule cells: 685 nCPM
  • prostatic hillock cells: 684 nCPM

Immune cell

  • naive B-cell: 6.3 nTPM
  • plasmacytoid DC: 6.1 nTPM
  • memory B-cell: 5.3 nTPM
  • NK-cell: 4.7 nTPM
  • myeloid DC: 4.5 nTPM
  • naive CD4 T-cell: 4.4 nTPM

Brain region

  • white matter: 329 nTPM
  • basal ganglia: 257 nTPM
  • cerebral cortex: 230 nTPM
  • midbrain: 205 nTPM
  • thalamus: 201 nTPM
  • amygdala: 193 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)
0.24
gnomAD pLI
1
gnomAD missense Z
3.44
DepMap mean gene effect
-0.57
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 20% 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 PTK2 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 PTK2 as an antibody target. Whether an autoantibody or antibody against PTK2 could matter depends on whether native PTK2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PTK2 is annotated at the cell surface, where native PTK2 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 PTK2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PTK2. 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).

© 2026 · Seroatlas, Discover Oregon LLC · Terms of use

Loading the interactive Seroatlas protein explorer...