DEFA4

Protein identityUniProt · HPA

UniProt accession

P12838

Gene

DEFA4

Ensembl

ENSG00000164821

Chromosome

8

Canonical length

97 aa

Protein class

Predicted secreted proteins

Secretome location

Secreted to blood

Quaternary structure

Homodimer

OverviewNCBI Gene

Defensins are a family of antimicrobial and cytotoxic peptides thought to be involved in host defense. They are abundant in the granules of neutrophils and also found in the epithelia of mucosal surfaces such as those of the intestine, respiratory tract, urinary tract, and vagina. Members of the defensin family are highly similar in protein sequence and distinguished by a conserved cysteine motif. Several alpha defensin genes are clustered on chromosome 8. This gene differs from other genes of this family by an extra 83-base segment that is apparently the result of a recent duplication within the coding region. The protein encoded by this gene, defensin, alpha 4, is found in the neutrophils; it exhibits corticostatic activity and inhibits corticotropin stimulated corticosterone production. [provided by RefSeq, Oct 2014]

Canonical amino-acid sequenceUniProt

97 residues, UniProt reviewed canonical sequence.

>P12838|DEFA4
     1  MRIIALLAAI LLVALQVRAG PLQARGDEAP GQEQRGPEDQ DISISFAWDK SSALQVSGST
    61  RGMVCSCRLV FCRRTELRVG NCLIGGVSFT YCCTRVD

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against DEFA4 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)

0.56

Highest tissue expression

2,548 nTPM

Expression across tissuesHPA

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)

1.38

gnomAD pLI

0.5

gnomAD missense Z

-2.34

DepMap mean gene effect

0.07

DepMap dependency class

none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

• antibacterial humoral response
• antifungal humoral response
• antimicrobial humoral immune response mediated by antimicrobial peptide
• antimicrobial humoral response
• defense response to fungus
• defense response to Gram-negative bacterium
• defense response to Gram-positive bacterium
• disruption of plasma membrane integrity in another organism
• innate immune response
• killing of cells of another organism

Molecular functions

• pore-forming activity
• protein homodimerization activity

Cellular components

• azurophil granule
• extracellular region
• extracellular space
• Golgi lumen
• specific granule lumen
• transport vesicle

Protein domainsUniProt · Pfam · InterPro

• Alpha-defensin, N-terminal
• Beta/alpha-defensin, C-terminal
• Alpha-defensin, C-terminal
• Alpha-defensin
• Mammalian defensin
• Defensin propeptide

KeywordsUniProt

• Antibiotic
• Antimicrobial
• Cytoplasmic vesicle
• Defensin
• Disulfide bond
• Fungicide
• Secreted
• Signal

InteractionsUniProt · HPA

Protein binding partners of DEFA4 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• CD4