Seroatlas · Human Serome Atlas

B9D1

B9 domain-containing protein 1

Also known as: B9, B9D1_HUMAN, EPPB9, MKS9, MKSR-1

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

Protein identityUniProt · HPA

UniProt accession
Q9UPM9
Gene
B9D1
Ensembl
ENSG00000108641
Chromosome
17
Canonical length
204 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Vesicles,Basal body,Cytosol,Acrosome,Equatorial segment,Mid piece,Principal piece,End piece

OverviewNCBI Gene

This gene encodes a B9 domain-containing protein, one of several that are involved in ciliogenesis. Alterations in expression of this gene have been found in a family with Meckel syndrome. Meckel syndrome has been associated with at least six different genes. This gene is located within the Smith-Magenis syndrome region on chromosome 17. [provided by RefSeq, Mar 2016]

Canonical amino-acid sequenceUniProt

204 residues, UniProt reviewed canonical sequence.

>Q9UPM9|B9D1
     1  MATASPSVFL LMVNGQVESA QFPEYDDLYC KYCFVYGQDW APTAGLEEGI SQITSKSQDV
    61  RQALVWNFPI DVTFKSTNPY GWPQIVLSVY GPDVFGNDVV RGYGAVHVPF SPGRHKRTIP
   121  MFVPESTSKL QKFTSWFMGR RPEYTDPKVV AQGEGREVTR VRSQGFVTLL FNVVTKDMRK
   181  LGYDTGPSDT QGVLGPSPPQ SFPQ

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against B9D1 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)
0.35
Highest tissue expression
87 nTPM

Expression across tissuesHPA

Tissue

  • choroid plexus: 87 nTPM
  • pituitary gland: 74 nTPM
  • testis: 71 nTPM
  • fallopian tube: 57 nTPM
  • basal ganglia: 51 nTPM
  • epididymis: 50 nTPM

Single-cell type

  • late primary spermatocytes: 334 nCPM
  • respiratory ciliated cells: 257 nCPM
  • fallopian tube ciliated cells: 236 nCPM
  • late spermatids: 224 nCPM
  • early spermatids: 213 nCPM
  • epididymal efferent duct ciliated cells: 177 nCPM

Immune cell

  • memory B-cell: 2.1 nTPM
  • intermediate monocyte: 1.8 nTPM
  • non-classical monocyte: 1.5 nTPM
  • MAIT T-cell: 0.9 nTPM
  • total PBMC: 0.9 nTPM
  • NK-cell: 0.8 nTPM

Brain region

  • choroid plexus: 72 nTPM
  • basal ganglia: 38 nTPM
  • midbrain: 36 nTPM
  • hypothalamus: 36 nTPM
  • hippocampal formation: 35 nTPM
  • amygdala: 34 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about B9D1.

Disease | AllUniProt

Conditions B9D1 is implicated in, by any mechanism.

Disease | GeneticClinVar

15 pathogenic / likely-pathogenic of 277 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.95
gnomAD pLI
0
gnomAD missense Z
0.1
DepMap mean gene effect
-0.04
DepMap dependency class
selective

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 B9D1 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 B9D1 as an antibody target. Whether an autoantibody or antibody against B9D1 could matter depends on whether native B9D1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

B9D1 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 B9D1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/B9D1. 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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