Seroatlas · Human Serome Atlas

AZIN2

Antizyme inhibitor 2

Also known as: ADC, AZIN2_HUMAN, KIAA1945, ODC-p, ODC1L, ODCp

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

Protein identityUniProt · HPA

UniProt accession
Q96A70
Gene
AZIN2
Ensembl
ENSG00000142920
Chromosome
1
Canonical length
460 aa
Protein class
Metabolic proteins, Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

The protein encoded by this gene belongs to the antizyme inhibitor family, which plays a role in cell growth and proliferation by maintaining polyamine homeostasis within the cell. Antizyme inhibitors are homologs of ornithine decarboxylase (ODC, the key enzyme in polyamine biosynthesis) that have lost the ability to decarboxylase ornithine; however, retain the ability to bind to antizymes. Antizymes negatively regulate intracellular polyamine levels by binding to ODC and targeting it for degradation, as well as by inhibiting polyamine uptake. Antizyme inhibitors function as positive regulators of polyamine levels by sequestering antizymes and neutralizing their effect. This gene encodes antizyme inhibitor 2, the second member of this gene family. Like antizyme inhibitor 1, antizyme inhibitor 2 interacts with all 3 antizymes and stimulates ODC activity and polyamine uptake. However, unlike antizyme inhibitor 1, which is ubiquitously expressed and localized in the nucleus and cytoplasm, antizyme inhibitor 2 is predominantly expressed in the brain and testis and localized in the endoplasmic reticulum-golgi intermediate compartment. Recent studies indicate that antizyme inhibitor 2 is also expressed in specific cell types in ovaries, adrenal glands and pancreas, and in mast cells. The exact function of this gene is not known, however, available data suggest its role in cell growth, spermiogenesis, vesicular trafficking and secretion. Accumulation of antizyme inhibitor 2 has also been observed in brains of patients with Alzheimer's disease. There has been confusion in literature and databases over the nomenclature of this gene, stemming from an earlier report that a human cDNA clone (identical to ODCp/AZIN2) had arginine decarboxylase (ADC) activity (PMID:14738999). Subsequent studies in human and mouse showed that antizyme inhibitor 2 was devoid of arginine decarboxylase activity (PMID:19956990). Alternatively spliced transcript variants have been described for this gene. [provided by RefSeq, Sep 2014]

Canonical amino-acid sequenceUniProt

460 residues, UniProt reviewed canonical sequence.

>Q96A70|AZIN2
     1  MAGYLSESDF VMVEEGFSTR DLLKELTLGA SQATTDEVAA FFVADLGAIV RKHFCFLKCL
    61  PRVRPFYAVK CNSSPGVLKV LAQLGLGFSC ANKAEMELVQ HIGIPASKII CANPCKQIAQ
   121  IKYAAKHGIQ LLSFDNEMEL AKVVKSHPSA KMVLCIATDD SHSLSCLSLK FGVSLKSCRH
   181  LLENAKKHHV EVVGVSFHIG SGCPDPQAYA QSIADARLVF EMGTELGHKM HVLDLGGGFP
   241  GTEGAKVRFE EIASVINSAL DLYFPEGCGV DIFAELGRYY VTSAFTVAVS IIAKKEVLLD
   301  QPGREEENGS TSKTIVYHLD EGVYGIFNSV LFDNICPTPI LQKKPSTEQP LYSSSLWGPA
   361  VDGCDCVAEG LWLPQLHVGD WLVFDNMGAY TVGMGSPFWG TQACHITYAM SRVAWEALRR
   421  QLMAAEQEDD VEGVCKPLSC GWEITDTLCV GPVFTPASIM

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against AZIN2 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
Cell surface
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.29
Highest tissue expression
30 nTPM

Expression across tissuesHPA

Tissue

  • testis: 30 nTPM
  • spinal cord: 22 nTPM
  • cerebral cortex: 12 nTPM
  • midbrain: 12 nTPM
  • hippocampal formation: 11 nTPM
  • basal ganglia: 9.7 nTPM

Single-cell type

  • late spermatids: 1,546 nCPM
  • early spermatids: 330 nCPM
  • microglia: 191 nCPM
  • pdcs: 99 nCPM
  • oligodendrocytes: 83 nCPM
  • late primary spermatocytes: 80 nCPM

Immune cell

  • plasmacytoid DC: 19 nTPM
  • basophil: 6.5 nTPM
  • memory CD4 T-cell: 1.6 nTPM
  • naive CD4 T-cell: 1.6 nTPM
  • naive CD8 T-cell: 1.6 nTPM
  • gdT-cell: 1.4 nTPM

Brain region

  • white matter: 23 nTPM
  • spinal cord: 17 nTPM
  • cerebellum: 14 nTPM
  • basal ganglia: 13 nTPM
  • medulla oblongata: 13 nTPM
  • pons: 13 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)
0.95
gnomAD pLI
0
DepMap mean gene effect
0.04
DepMap dependency class
none

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of AZIN2 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 AZIN2 as an antibody target. Whether an autoantibody or antibody against AZIN2 could matter depends on whether native AZIN2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

AZIN2 is annotated at the cell surface, where native AZIN2 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label AZIN2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/AZIN2. 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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