Seroatlas · Human Serome Atlas

SEMA3B

Semaphorin-3B

Also known as: LUCA-1, SEM3B_HUMAN, SemA, sema5, SEMAA, semaV

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

Protein identityUniProt · HPA

UniProt accession
Q13214
Gene
SEMA3B
Ensembl
ENSG00000012171
Chromosome
3
Canonical length
749 aa
Protein class
Cancer-related genes, Predicted intracellular proteins, Predicted secreted proteins
Secretome location
Secreted in other tissues

OverviewNCBI Gene

The protein encoded by this gene belongs to the class-3 semaphorin/collapsin family, whose members function in growth cone guidance during neuronal development. This family member inhibits axonal extension and has been shown to act as a tumor suppressor by inducing apoptosis. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Feb 2014]

Canonical amino-acid sequenceUniProt

749 residues, UniProt reviewed canonical sequence.

>Q13214|SEMA3B
     1  MGRAGAAAVI PGLALLWAVG LGSAAPSPPR LRLSFQELQA WHGLQTFSLE RTCCYQALLV
    61  DEERGRLFVG AENHVASLNL DNISKRAKKL AWPAPVEWRE ECNWAGKDIG TECMNFVKLL
   121  HAYNRTHLLA CGTGAFHPTC AFVEVGHRAE EPVLRLDPGR IEDGKGKSPY DPRHRAASVL
   181  VGEELYSGVA ADLMGRDFTI FRSLGQRPSL RTEPHDSRWL NEPKFVKVFW IPESENPDDD
   241  KIYFFFRETA VEAAPALGRL SVSRVGQICR NDVGGQRSLV NKWTTFLKAR LVCSVPGVEG
   301  DTHFDQLQDV FLLSSRDHRT PLLYAVFSTS SSIFQGSAVC VYSMNDVRRA FLGPFAHKEG
   361  PMHQWVSYQG RVPYPRPGMC PSKTFGTFSS TKDFPDDVIQ FARNHPLMYN SVLPTGGRPL
   421  FLQVGANYTF TQIAADRVAA ADGHYDVLFI GTDVGTVLKV ISVPKGSRPS AEGLLLEELH
   481  VFEDSAAVTS MQISSKRHQL YVASRSAVAQ IALHRCAAHG RVCTECCLAR DPYCAWDGVA
   541  CTRFQPSAKR RFRRQDVRNG DPSTLCSGDS SRPALLEHKV FGVEGSSAFL ECEPRSLQAR
   601  VEWTFQRAGV TAHTQVLAEE RTERTARGLL LRRLRRRDSG VYLCAAVEQG FTQPLRRLSL
   661  HVLSATQAER LARAEEAAPA APPGPKLWYR DFLQLVEPGG GGSANSLRMC RPQPALQSLP
   721  LESRRKGRNR RTHAPEPRAE RGPRSATHW

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SEMA3B 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
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.31
Highest tissue expression
163 nTPM

Expression across tissuesHPA

Tissue

  • adrenal gland: 163 nTPM
  • spinal cord: 160 nTPM
  • midbrain: 108 nTPM
  • hippocampal formation: 83 nTPM
  • basal ganglia: 80 nTPM
  • kidney: 68 nTPM

Single-cell type

  • enterocytes: 379 nCPM
  • schwann cells: 365 nCPM
  • alveolar cells type 1: 261 nCPM
  • endometrial secretory cells: 216 nCPM
  • oligodendrocytes: 203 nCPM
  • syncytiotrophoblasts: 154 nCPM

Immune cell

  • eosinophil: 0.8 nTPM
  • myeloid DC: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • white matter: 361 nTPM
  • medulla oblongata: 255 nTPM
  • basal ganglia: 248 nTPM
  • thalamus: 219 nTPM
  • midbrain: 202 nTPM
  • pons: 187 nTPM

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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SEMA3B as an antibody target. Whether an autoantibody or antibody against SEMA3B could matter depends on whether native SEMA3B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SEMA3B is annotated as secreted, so native SEMA3B circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label SEMA3B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SEMA3B. 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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