Seroatlas · Human Serome Atlas

PFN4

Profilin-4

Also known as: PROF4_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q8NHR9
Gene
PFN4
Ensembl
ENSG00000176732
Chromosome
2
Canonical length
129 aa
Protein class
Predicted intracellular proteins

OverviewNCBI Gene

Predicted to enable actin monomer binding activity. Predicted to be involved in acrosome assembly; manchette assembly; and sperm flagellum assembly. Predicted to be located in cytoplasm. Predicted to be active in cell cortex. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

129 residues, UniProt reviewed canonical sequence.

>Q8NHR9|PFN4
     1  MSHLQSLLLD TLLGTKHVDS AALIKIQERS LCVASPGFNV TPSDVRTLVN GFAKNPLQAR
    61  REGLYFKGKD YRCVRADEYS LYAKNENTGV VVVKTHLYLL VATYTEGMYP SICVEATESL
   121  GDYLRKKGS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PFN4 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)
0.28
Highest tissue expression
78 nTPM

Expression across tissuesHPA

Tissue

  • testis: 78 nTPM
  • ovary: 3.1 nTPM
  • retina: 2.7 nTPM
  • pituitary gland: 2.3 nTPM
  • cervix: 2 nTPM
  • epididymis: 1.8 nTPM

Single-cell type

  • late primary spermatocytes: 1,354 nCPM
  • early spermatids: 477 nCPM
  • early primary spermatocytes: 73 nCPM
  • late spermatids: 58 nCPM
  • adrenal medulla cells: 11 nCPM
  • sertoli cells: 11 nCPM

Immune cell

  • naive CD8 T-cell: 0.8 nTPM
  • naive B-cell: 0.2 nTPM
  • gdT-cell: 0.1 nTPM
  • MAIT T-cell: 0.1 nTPM
  • memory CD8 T-cell: 0.1 nTPM
  • NK-cell: 0.1 nTPM

Brain region

  • cerebral cortex: 7 nTPM
  • amygdala: 6.9 nTPM
  • cerebellum: 6.5 nTPM
  • midbrain: 6.3 nTPM
  • white matter: 6.2 nTPM
  • thalamus: 6 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)
1.41
gnomAD pLI
0
gnomAD missense Z
0.02
DepMap mean gene effect
0.06
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads PFN4 as an antibody target. Whether an autoantibody or antibody against PFN4 could matter depends on whether native PFN4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PFN4 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 PFN4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PFN4. 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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