Seroatlas · Human Serome Atlas

STXBP5

Syntaxin-binding protein 5

Also known as: LLGL3, STXB5_HUMAN, tomosyn, tomosyn-1

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

Protein identityUniProt · HPA

UniProt accession
Q5T5C0
Gene
STXBP5
Ensembl
ENSG00000164506
Chromosome
6
Canonical length
1151 aa
Protein class
Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

Syntaxin 1 is a component of the 7S and 20S SNARE complexes which are involved in docking and fusion of synaptic vesicles with the presynaptic plasma membrane. This gene encodes a syntaxin 1 binding protein. In rat, a similar protein dissociates syntaxin 1 from the Munc18/n-Sec1/rbSec1 complex to form a 10S complex, an intermediate which can be converted to the 7S SNARE complex. Thus this protein is thought to be involved in neurotransmitter release by stimulating SNARE complex formation. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

1151 residues, UniProt reviewed canonical sequence.

>Q5T5C0|STXBP5
     1  MRKFNIRKVL DGLTAGSSSA SQQQQQQHPP GNREPEIQET LQSEHFQLCK TVRHGFPYQP
    61  SALAFDPVQK ILAVGTQTGA LRLFGRPGVE CYCQHDSGAA VIQLQFLINE GALVSALADD
   121  TLHLWNLRQK RPAILHSLKF CRERVTFCHL PFQSKWLYVG TERGNIHIVN VESFTLSGYV
   181  IMWNKAIELS SKSHPGPVVH ISDNPMDEGK LLIGFESGTV VLWDLKSKKA DYRYTYDEAI
   241  HSVAWHHEGK QFICSHSDGT LTIWNVRSPA KPVQTITPHG KQLKDGKKPE PCKPILKVEF
   301  KTTRSGEPFI ILSGGLSYDT VGRRPCLTVM HGKSTAVLEM DYSIVDFLTL CETPYPNDFQ
   361  EPYAVVVLLE KDLVLIDLAQ NGYPIFENPY PLSIHESPVT CCEYFADCPV DLIPALYSVG
   421  ARQKRQGYSK KEWPINGGNW GLGAQSYPEI IITGHADGSV KFWDASAITL QVLYKLKTSK
   481  VFEKSRNKDD RPNTDIVDED PYAIQIISWC PESRMLCIAG VSAHVIIYRF SKQEVITEVI
   541  PMLEVRLLYE INDVETPEGE QPPPLPTPVG GSNPQPIPPQ SHPSTSSSSS DGLRDNVPCL
   601  KVKNSPLKQS PGYQTELVIQ LVWVGGEPPQ QITSLAVNSS YGLVVFGNCN GIAMVDYLQK
   661  AVLLNLGTIE LYGSNDPYRR EPRSPRKSRQ PSGAGLCDIS EGTVVPEDRC KSPTSGSSSP
   721  HNSDDEQKMN NFIEKVKTKS RKFSKMVAND IAKMSRKLSL PTDLKPDLDV KDNSFSRSRS
   781  SSVTSIDKES REAISALHFC ETFTRKTDSS PSPCLWVGTT LGTVLVIALN LPPGGEQRLL
   841  QPVIVSPSGT ILRLKGAILR MAFLDTTGCL IPPAYEPWRE HNVPEEKDEK EKLKKRRPVS
   901  VSPSSSQEIS ENQYAVICSE KQAKVISLPT QNCAYKQNIT ETSFVLRGDI VALSNSICLA
   961  CFCANGHIMT FSLPSLRPLL DVYYLPLTNM RIARTFCFTN NGQALYLVSP TEIQRLTYSQ
  1021  ETCENLQEML GELFTPVETP EAPNRGFFKG LFGGGAQSLD REELFGESSS GKASRSLAQH
  1081  IPGPGGIEGV KGAASGVVGE LARARLALDE RGQKLGDLEE RTAAMLSSAE SFSKHAHEIM
  1141  LKYKDKKWYQ F

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against STXBP5 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)
0.33
Highest tissue expression
36 nTPM

Expression across tissuesHPA

Tissue

  • parathyroid gland: 36 nTPM
  • cerebral cortex: 9.3 nTPM
  • skin: 8.8 nTPM
  • cerebellum: 8.5 nTPM
  • testis: 8.2 nTPM
  • pancreas: 7.6 nTPM

Single-cell type

  • neutrophils: 1,612 nCPM
  • neutrophil progenitors: 1,588 nCPM
  • megakaryocyte-erythroid progenitors: 830 nCPM
  • megakaryocyte progenitors: 800 nCPM
  • prostatic glandular cells: 760 nCPM
  • retinal amacrine cells: 692 nCPM

Immune cell

  • eosinophil: 1.1 nTPM
  • neutrophil: 0.8 nTPM
  • basophil: 0.3 nTPM
  • gdT-cell: 0.3 nTPM
  • naive CD8 T-cell: 0.3 nTPM
  • naive CD4 T-cell: 0.2 nTPM

Brain region

  • cerebellum: 26 nTPM
  • cerebral cortex: 20 nTPM
  • basal ganglia: 16 nTPM
  • hippocampal formation: 16 nTPM
  • white matter: 16 nTPM
  • hypothalamus: 14 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)
0.26
gnomAD pLI
1
gnomAD missense Z
3
DepMap mean gene effect
0.01
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 STXBP5 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 STXBP5 as an antibody target. Whether an autoantibody or antibody against STXBP5 could matter depends on whether native STXBP5 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

STXBP5 is annotated at the cell surface, where native STXBP5 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 STXBP5 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/STXBP5. 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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