Seroatlas · Human Serome Atlas

MSMB

Beta-microseminoprotein

Also known as: IGBF, MSMB_HUMAN, MSP, MSPB, PN44, PRPS, PSP, PSP-94, PSP57, PSP94

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

Protein identityUniProt · HPA

UniProt accession
P08118
Gene
MSMB
Ensembl
ENSG00000263639
Chromosome
10
Canonical length
114 aa
Protein class
Cancer-related genes, Disease related genes, Human disease related genes, Predicted membrane proteins, Predicted secreted proteins
Secretome location
Secreted in male reproductive system
Quaternary structure
Homodimer

OverviewNCBI Gene

The protein encoded by this gene is a member of the immunoglobulin binding factor family. It is synthesized by the epithelial cells of the prostate gland and secreted into the seminal plasma. This protein has inhibin-like activity. It may have a role as an autocrine paracrine factor in uterine, breast and other female reproductive tissues. The expression of the encoded protein is found to be decreased in prostate cancer. Two alternatively spliced transcript variants encoding different isoforms are described for this gene. The use of alternate polyadenylation sites has been found for this gene. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

114 residues, UniProt reviewed canonical sequence.

>P08118|MSMB
     1  MNVLLGSVVI FATFVTLCNA SCYFIPNEGV PGDSTRKCMD LKGNKHPINS EWQTDNCETC
    61  TCYETEISCC TLVSTPVGYD KDNCQRIFKK EDCKYIVVEK KDPKKTCSVS EWII

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MSMB 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)
0.42
Highest tissue expression
8,772 nTPM

Expression across tissuesHPA

Tissue

  • prostate: 8,772 nTPM
  • stomach: 521 nTPM
  • epididymis: 43 nTPM
  • skin: 39 nTPM
  • salivary gland: 32 nTPM
  • lung: 31 nTPM

Single-cell type

  • prostatic glandular cells: 24,516 nCPM
  • conjunctival goblet cells: 5,014 nCPM
  • respiratory secretory cells: 3,957 nCPM
  • respiratory deuterosomal cells: 2,429 nCPM
  • submucosal glandular cells: 864 nCPM
  • foveolar cells: 359 nCPM

Immune cell

  • eosinophil: 0.2 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • hypothalamus: 0.1 nTPM
  • medulla oblongata: 0.1 nTPM
  • pons: 0.1 nTPM
  • white matter: 0.1 nTPM
  • amygdala: 0 nTPM
  • basal ganglia: 0 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MSMB.

Disease | AllUniProt

Conditions MSMB is implicated in, by any mechanism.

  • Prostate cancer, hereditary, 13 (HPC13) MIM:611928

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)
1.58
gnomAD pLI
0.02
gnomAD missense Z
0.79
DepMap mean gene effect
0
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

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

MSMB is annotated as secreted, so native MSMB 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 MSMB as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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