Seroatlas · Human Serome Atlas

SEMA4B

Semaphorin-4B

Also known as: KIAA1745, MGC131831, SEM4B_HUMAN, SEMAC, SemC

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

Protein identityUniProt · HPA

UniProt accession: Q9NPR2
Gene: SEMA4B
Ensembl: ENSG00000185033
Chromosome: 15
Canonical length: 837 aa
Protein class: Predicted intracellular proteins, Predicted membrane proteins
Subcellular location: Nucleoplasm,Vesicles,Cell Junctions

OverviewNCBI Gene

Predicted to enable chemorepellent activity; neuropilin binding activity; and semaphorin receptor binding activity. Predicted to be involved in several processes, including axon guidance; neural crest cell migration; and semaphorin-plexin signaling pathway. Predicted to be located in membrane and synapse. Predicted to be active in glutamatergic synapse and postsynaptic density membrane. [provided by Alliance of Genome Resources, Apr 2025]

Canonical amino-acid sequenceUniProt

837 residues, UniProt reviewed canonical sequence.

>Q9NPR2|SEMA4B
     1  MLRTAMGLRS WLAAPWGALP PRPPLLLLLL LLLLLQPPPP TWALSPRISL PLGSEERPFL
    61  RFEAEHISNY TALLLSRDGR TLYVGAREAL FALSSNLSFL PGGEYQELLW GADAEKKQQC
   121  SFKGKDPQRD CQNYIKILLP LSGSHLFTCG TAAFSPMCTY INMENFTLAR DEKGNVLLED
   181  GKGRCPFDPN FKSTALVVDG ELYTGTVSSF QGNDPAISRS QSLRPTKTES SLNWLQDPAF
   241  VASAYIPESL GSLQGDDDKI YFFFSETGQE FEFFENTIVS RIARICKGDE GGERVLQQRW
   301  TSFLKAQLLC SRPDDGFPFN VLQDVFTLSP SPQDWRDTLF YGVFTSQWHR GTTEGSAVCV
   361  FTMKDVQRVF SGLYKEVNRE TQQWYTVTHP VPTPRPGACI TNSARERKIN SSLQLPDRVL
   421  NFLKDHFLMD GQVRSRMLLL QPQARYQRVA VHRVPGLHHT YDVLFLGTGD GRLHKAVSVG
   481  PRVHIIEELQ IFSSGQPVQN LLLDTHRGLL YAASHSGVVQ VPMANCSLYR SCGDCLLARD
   541  PYCAWSGSSC KHVSLYQPQL ATRPWIQDIE GASAKDLCSA SSVVSPSFVP TGEKPCEQVQ
   601  FQPNTVNTLA CPLLSNLATR LWLRNGAPVN ASASCHVLPT GDLLLVGTQQ LGEFQCWSLE
   661  EGFQQLVASY CPEVVEDGVA DQTDEGGSVP VIISTSRVSA PAGGKASWGA DRSYWKEFLV
   721  MCTLFVLAVL LPVLFLLYRH RNSMKVFLKQ GECASVHPKT CPVVLPPETR PLNGLGPPST
   781  PLDHRGYQSL SDSPPGSRVF TESEKRPLSI QDSFVEVSPV CPRPRVRLGS EIRDSVV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SEMA4B 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: 1
Mean surface accessibility (rSASA): 0.34
Highest tissue expression: 120 nTPM

Expression across tissuesHPA

Tissue

esophagus: 120 nTPM
vagina: 59 nTPM
skin: 50 nTPM
colon: 47 nTPM
cervix: 46 nTPM
kidney: 43 nTPM

Single-cell type

urothelial cells: 419 nCPM
prostatic hillock cells: 285 nCPM
esophageal suprabasal cells: 278 nCPM
ocular epithelial cells: 245 nCPM
esophageal apical cells: 200 nCPM
papillary tip epithelial cells: 184 nCPM

Immune cell

memory B-cell: 17 nTPM
naive B-cell: 15 nTPM
neutrophil: 5.2 nTPM
non-classical monocyte: 2.8 nTPM
classical monocyte: 2.4 nTPM
total PBMC: 1.5 nTPM

Brain region

white matter: 44 nTPM
midbrain: 41 nTPM
medulla oblongata: 39 nTPM
thalamus: 38 nTPM
basal ganglia: 35 nTPM
spinal cord: 34 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): 0.53
gnomAD pLI: 0
gnomAD missense Z: 0.96
DepMap mean gene effect: -0.06
DepMap dependency class: selective

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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SEMA4B as an antibody target. Whether an autoantibody or antibody against SEMA4B could matter depends on whether native SEMA4B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SEMA4B is annotated at the cell surface, where native SEMA4B 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 SEMA4B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...