Seroatlas · Human Serome Atlas

STK26

Serine/threonine-protein kinase 26

Also known as: MASK, MST4, STK26_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9P289
Gene
STK26
Ensembl
ENSG00000134602
Chromosome
X
Canonical length
416 aa
Protein class
Enzymes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Golgi apparatus,Centrosome,Cytosol
Quaternary structure
Homodimer

OverviewNCBI Gene

The product of this gene is a member of the GCK group III family of kinases, which are a subset of the Ste20-like kinases. The encoded protein contains an amino-terminal kinase domain, and a carboxy-terminal regulatory domain that mediates homodimerization. The protein kinase localizes to the Golgi apparatus and is specifically activated by binding to the Golgi matrix protein GM130. It is also cleaved by caspase-3 in vitro, and may function in the apoptotic pathway. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of some of these variants has not been determined. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

416 residues, UniProt reviewed canonical sequence.

>Q9P289|STK26
     1  MAHSPVAVQV PGMQNNIADP EELFTKLERI GKGSFGEVFK GIDNRTQQVV AIKIIDLEEA
    61  EDEIEDIQQE ITVLSQCDSS YVTKYYGSYL KGSKLWIIME YLGGGSALDL LRAGPFDEFQ
   121  IATMLKEILK GLDYLHSEKK IHRDIKAANV LLSEQGDVKL ADFGVAGQLT DTQIKRNTFV
   181  GTPFWMAPEV IQQSAYDSKA DIWSLGITAI ELAKGEPPNS DMHPMRVLFL IPKNNPPTLV
   241  GDFTKSFKEF IDACLNKDPS FRPTAKELLK HKFIVKNSKK TSYLTELIDR FKRWKAEGHS
   301  DDESDSEGSD SESTSRENNT HPEWSFTTVR KKPDPKKVQN GAEQDLVQTL SCLSMIITPA
   361  FAELKQQDEN NASRNQAIEE LEKSIAVAEA ACPGITDKMV KKLIEKFQKC SADESP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against STK26 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.31
Highest tissue expression
66 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 66 nTPM
  • epididymis: 53 nTPM
  • endometrium: 47 nTPM
  • thymus: 39 nTPM
  • smooth muscle: 36 nTPM
  • seminal vesicle: 34 nTPM

Single-cell type

  • neutrophil progenitors: 192 nCPM
  • neutrophils: 186 nCPM
  • monocyte progenitors: 102 nCPM
  • thymocytes: 102 nCPM
  • innate lymphoid cells: 85 nCPM
  • ocular epithelial cells: 83 nCPM

Immune cell

  • basophil: 59 nTPM
  • NK-cell: 41 nTPM
  • eosinophil: 32 nTPM
  • gdT-cell: 23 nTPM
  • non-classical monocyte: 23 nTPM
  • MAIT T-cell: 22 nTPM

Brain region

  • hypothalamus: 7.5 nTPM
  • basal ganglia: 5.6 nTPM
  • choroid plexus: 5.3 nTPM
  • cerebellum: 3.5 nTPM
  • medulla oblongata: 1.7 nTPM
  • midbrain: 1.6 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)
0.54
gnomAD pLI
0.31
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

InteractionsUniProt · HPA

Protein binding partners of STK26 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 STK26 as an antibody target. Whether an autoantibody or antibody against STK26 could matter depends on whether native STK26 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

STK26 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label STK26 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/STK26. 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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