Seroatlas · Human Serome Atlas

SEPTIN3

Neuronal-specific septin-3

Also known as: SEP3, SEPT3, SEPT3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9UH03
Gene
SEPTIN3
Ensembl
ENSG00000100167
Chromosome
22
Canonical length
358 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Plasma membrane,Actin filaments,Primary cilium

OverviewNCBI Gene

This gene belongs to the septin family of GTPases. Members of this family are required for cytokinesis. Expression is upregulated by retinoic acid in a human teratocarcinoma cell line. The specific function of this gene has not been determined. Alternative splicing of this gene results in several transcript variants encoding different isoforms. [provided by RefSeq, May 2018]

Canonical amino-acid sequenceUniProt

358 residues, UniProt reviewed canonical sequence.

>Q9UH03|SEPTIN3
     1  MSKGLPETRT DAAMSELVPE PRPKPAVPMK PMSINSNLLG YIGIDTIIEQ MRKKTMKTGF
    61  DFNIMVVGQS GLGKSTLVNT LFKSQVSRKA SSWNREEKIP KTVEIKAIGH VIEEGGVKMK
   121  LTVIDTPGFG DQINNENCWE PIEKYINEQY EKFLKEEVNI ARKKRIPDTR VHCCLYFISP
   181  TGHSLRPLDL EFMKHLSKVV NIIPVIAKAD TMTLEEKSEF KQRVRKELEV NGIEFYPQKE
   241  FDEDLEDKTE NDKIRQESMP FAVVGSDKEY QVNGKRVLGR KTPWGIIEVE NLNHCEFALL
   301  RDFVIRTHLQ DLKEVTHNIH YETYRAKRLN DNGGLPPGEG LLGTVLPPVP ATPCPTAE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SEPTIN3 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)
0.38
Highest tissue expression
254 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 254 nTPM
  • amygdala: 198 nTPM
  • hippocampal formation: 190 nTPM
  • cerebellum: 146 nTPM
  • basal ganglia: 130 nTPM
  • hypothalamus: 96 nTPM

Single-cell type

  • brain excitatory neurons: 56 nCPM
  • late spermatids: 47 nCPM
  • extravillous trophoblasts: 46 nCPM
  • brain inhibitory neurons: 44 nCPM
  • other brain neurons: 43 nCPM
  • early spermatids: 30 nCPM

Immune cell

  • basophil: 0.4 nTPM
  • myeloid DC: 0.2 nTPM
  • plasmacytoid DC: 0.1 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM

Brain region

  • cerebral cortex: 462 nTPM
  • hippocampal formation: 317 nTPM
  • basal ganglia: 290 nTPM
  • white matter: 287 nTPM
  • amygdala: 245 nTPM
  • thalamus: 172 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
0.09
DepMap mean gene effect
-0.08
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 SEPTIN3 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 SEPTIN3 as an antibody target. Whether an autoantibody or antibody against SEPTIN3 could matter depends on whether native SEPTIN3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SEPTIN3 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 SEPTIN3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SEPTIN3. 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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