Seroatlas · Human Serome Atlas

DEFB105A

Beta-defensin 105

Also known as: D105A_HUMAN, DEFB-5, DEFB105, DEFB105B

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

Protein identityUniProt · HPA

UniProt accession
Q8NG35
Gene
DEFB105A
Ensembl
ENSG00000186562
Chromosome
8
Canonical length
78 aa
Protein class
Predicted secreted proteins
Secretome location
Secreted in male reproductive system

OverviewNCBI Gene

Defensins form a family of antimicrobial and cytotoxic peptides made by neutrophils. Defensins are short, processed peptide molecules that are classified by structure into three groups: alpha-defensins, beta-defensins and theta-defensins. All beta-defensin genes are densely clustered in four to five syntenic chromosomal regions. Chromosome 8p23 contains at least two copies of the duplicated beta-defensin cluster. This duplication results in two identical copies of defensin, beta 105, DEFB105A and DEFB105B, in tail-to-tail orientation. This gene, DEFB105A, represents the more centromeric copy. [provided by RefSeq, Oct 2014]

Canonical amino-acid sequenceUniProt

78 residues, UniProt reviewed canonical sequence.

>Q8NG35|DEFB105A
     1  MALIRKTFYF LFAMFFILVQ LPSGCQAGLD FSQPFPSGEF AVCESCKLGR GKCRKECLEN
    61  EKPDGNCRLN FLCCRQRI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against DEFB105A 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)
0.49
Highest tissue expression
1,166 nTPM

Expression across tissuesHPA

Tissue

  • epididymis: 1,166 nTPM
  • bone marrow: 0.5 nTPM
  • skin: 0.4 nTPM
  • appendix: 0.3 nTPM
  • lymph node: 0.3 nTPM
  • retina: 0.3 nTPM

Single-cell type

  • adipocytes: 0 nCPM
  • adrenal cortex cells: 0 nCPM
  • adrenal medulla cells: 0 nCPM
  • alveolar cells type 1: 0 nCPM
  • alveolar cells type 2: 0 nCPM
  • astrocytes: 0 nCPM

Immune cell

  • basophil: 2.9 nTPM
  • neutrophil: 1.4 nTPM
  • NK-cell: 0.9 nTPM
  • naive B-cell: 0.7 nTPM
  • memory B-cell: 0.5 nTPM
  • plasmacytoid DC: 0.5 nTPM

Brain region

  • cerebellum: 6.5 nTPM
  • white matter: 6 nTPM
  • cerebral cortex: 5.5 nTPM
  • amygdala: 5.2 nTPM
  • medulla oblongata: 5.2 nTPM
  • thalamus: 5.2 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)
1.76
gnomAD pLI
0.38
gnomAD missense Z
-0.36

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 0% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads DEFB105A as an antibody target. Whether an autoantibody or antibody against DEFB105A could matter depends on whether native DEFB105A is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

DEFB105A is annotated as secreted, so native DEFB105A 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 DEFB105A as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/DEFB105A. 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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