Seroatlas · Human Serome Atlas

STXBP2

Syntaxin-binding protein 2

Also known as: Hunc18b, MUNC18-2, STXB2_HUMAN, Unc18-2, UNC18B

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

Protein identityUniProt · HPA

UniProt accession
Q15833
Gene
STXBP2
Ensembl
ENSG00000076944
Chromosome
19
Canonical length
593 aa
Protein class
Disease related genes, Human disease related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

This gene encodes a member of the STXBP/unc-18/SEC1 family. The encoded protein is involved in intracellular trafficking, control of SNARE (soluble NSF attachment protein receptor) complex assembly, and the release of cytotoxic granules by natural killer cells. Mutations in this gene are associated with familial hemophagocytic lymphohistiocytosis. Alternatively spliced transcript variants encoding different isoforms have been noted for this gene. [provided by RefSeq, Jan 2013]

Canonical amino-acid sequenceUniProt

593 residues, UniProt reviewed canonical sequence.

>Q15833|STXBP2
     1  MAPSGLKAVV GEKILSGVIR SVKKDGEWKV LIMDHPSMRI LSSCCKMSDI LAEGITIVED
    61  INKRREPIPS LEAIYLLSPT EKSVQALIKD FQGTPTFTYK AAHIFFTDTC PEPLFSELGR
   121  SRLAKVVKTL KEIHLAFLPY EAQVFSLDAP HSTYNLYCPF RAEERTRQLE VLAQQIATLC
   181  ATLQEYPAIR YRKGPEDTAQ LAHAVLAKLN AFKADTPSLG EGPEKTRSQL LIMDRAADPV
   241  SPLLHELTFQ AMAYDLLDIE QDTYRYETTG LSEAREKAVL LDEDDDLWVE LRHMHIADVS
   301  KKVTELLRTF CESKRLTTDK ANIKDLSQIL KKMPQYQKEL NKYSTHLHLA DDCMKHFKGS
   361  VEKLCSVEQD LAMGSDAEGE KIKDSMKLIV PVLLDAAVPA YDKIRVLLLY ILLRNGVSEE
   421  NLAKLIQHAN VQAHSSLIRN LEQLGGTVTN PGGSGTSSRL EPRERMEPTY QLSRWTPVIK
   481  DVMEDAVEDR LDRNLWPFVS DPAPTASSQA AVSARFGHWH KNKAGIEARA GPRLIVYVMG
   541  GVAMSEMRAA YEVTRATEGK WEVLIGSSHI LTPTRFLDDL KALDKKLEDI ALP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against STXBP2 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)
0.26
Highest tissue expression
153 nTPM

Expression across tissuesHPA

Tissue

  • spleen: 153 nTPM
  • bone marrow: 110 nTPM
  • lung: 82 nTPM
  • pancreas: 77 nTPM
  • salivary gland: 70 nTPM
  • testis: 69 nTPM

Single-cell type

  • neutrophils: 901 nCPM
  • platelets: 481 nCPM
  • late spermatids: 321 nCPM
  • neutrophil progenitors: 301 nCPM
  • monocytes: 274 nCPM
  • megakaryocytes: 253 nCPM

Immune cell

  • non-classical monocyte: 838 nTPM
  • intermediate monocyte: 542 nTPM
  • classical monocyte: 419 nTPM
  • neutrophil: 296 nTPM
  • total PBMC: 251 nTPM
  • eosinophil: 218 nTPM

Brain region

  • cerebral cortex: 11 nTPM
  • choroid plexus: 9.5 nTPM
  • thalamus: 8.2 nTPM
  • medulla oblongata: 7.9 nTPM
  • white matter: 7.7 nTPM
  • pons: 7.1 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about STXBP2.

Disease | AllUniProt

Conditions STXBP2 is implicated in, by any mechanism.

  • Hemophagocytic lymphohistiocytosis, familial, 5, with or without microvillus inclusion disease (FHL5) MIM:613101

Disease | GeneticClinVar

101 pathogenic / likely-pathogenic of 1,250 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)
0.84
gnomAD pLI
0
gnomAD missense Z
0.48
DepMap mean gene effect
-0.06
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 STXBP2 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 STXBP2 as an antibody target. Whether an autoantibody or antibody against STXBP2 could matter depends on whether native STXBP2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

STXBP2 is annotated at the cell surface, where native STXBP2 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 STXBP2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/STXBP2. 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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