Seroatlas · Human Serome Atlas

B9D2

B9 domain-containing protein 2

Also known as: B9D2_HUMAN, MGC4093, MKS10, MKSR-2

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

Protein identityUniProt · HPA

UniProt accession
Q9BPU9
Gene
B9D2
Ensembl
ENSG00000123810
Chromosome
19
Canonical length
175 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoli,Golgi apparatus,Vesicles,Centrosome,Basal body

OverviewNCBI Gene

This gene encodes a B9 domain protein, which are exclusively found in ciliated organisms. The gene is upregulated during mucociliary differentiation, and the encoded protein localizes to basal bodies and cilia. Disrupting expression of this gene results in ciliogenesis defects. [provided by RefSeq, Oct 2009]

Canonical amino-acid sequenceUniProt

175 residues, UniProt reviewed canonical sequence.

>Q9BPU9|B9D2
     1  MAEVHVIGQI IGASGFSESS LFCKWGIHTG AAWKLLSGVR EGQTQVDTPQ IGDMAYWSHP
    61  IDLHFATKGL QGWPRLHFQV WSQDSFGRCQ LAGYGFCHVP SSPGTHQLAC PTWRPLGSWR
   121  EQLARAFVGG GPQLLHGDTI YSGADRYRLH TAAGGTVHLE IGLLLRNFDR YGVEC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against B9D2 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)
0.29
Highest tissue expression
17 nTPM

Expression across tissuesHPA

Tissue

  • choroid plexus: 17 nTPM
  • fallopian tube: 9.9 nTPM
  • kidney: 8.8 nTPM
  • bone marrow: 8.3 nTPM
  • testis: 8.3 nTPM
  • adrenal gland: 8.2 nTPM

Single-cell type

  • respiratory ciliated cells: 96 nCPM
  • fallopian tube ciliated cells: 80 nCPM
  • endometrial ciliated cells: 64 nCPM
  • late spermatids: 56 nCPM
  • epididymal efferent duct ciliated cells: 53 nCPM
  • neutrophils: 37 nCPM

Immune cell

  • neutrophil: 128 nTPM
  • basophil: 47 nTPM
  • classical monocyte: 32 nTPM
  • plasmacytoid DC: 26 nTPM
  • eosinophil: 26 nTPM
  • T-reg: 25 nTPM

Brain region

  • choroid plexus: 13 nTPM
  • hypothalamus: 6.8 nTPM
  • midbrain: 5 nTPM
  • spinal cord: 4.4 nTPM
  • thalamus: 4.4 nTPM
  • hippocampal formation: 4.3 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about B9D2.

Disease | AllUniProt

Conditions B9D2 is implicated in, by any mechanism.

Disease | GeneticClinVar

10 pathogenic / likely-pathogenic of 107 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)
1.58
gnomAD pLI
0
gnomAD missense Z
-0.13
DepMap mean gene effect
-0.05
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

InteractionsUniProt · HPA

Protein binding partners of B9D2 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 B9D2 as an antibody target. Whether an autoantibody or antibody against B9D2 could matter depends on whether native B9D2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

B9D2 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 B9D2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/B9D2. 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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