Seroatlas · Human Serome Atlas

CNN2

Calponin-2

Also known as: CNN2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q99439
Gene
CNN2
Ensembl
ENSG00000064666
Chromosome
19
Canonical length
309 aa
Protein class
Plasma proteins, Predicted intracellular proteins
Subcellular location
Actin filaments

OverviewNCBI Gene

The protein encoded by this gene, which can bind actin, calmodulin, troponin C, and tropomyosin, may function in the structural organization of actin filaments. The encoded protein could play a role in smooth muscle contraction and cell adhesion. Several pseudogenes of this gene have been identified, and are present on chromosomes 1, 2, 3, 6, 9, 11, 13, 15, 16, 21 and 22. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2015]

Canonical amino-acid sequenceUniProt

309 residues, UniProt reviewed canonical sequence.

>Q99439|CNN2
     1  MSSTQFNKGP SYGLSAEVKN RLLSKYDPQK EAELRTWIEG LTGLSIGPDF QKGLKDGTIL
    61  CTLMNKLQPG SVPKINRSMQ NWHQLENLSN FIKAMVSYGM NPVDLFEAND LFESGNMTQV
   121  QVSLLALAGK AKTKGLQSGV DIGVKYSEKQ ERNFDDATMK AGQCVIGLQM GTNKCASQSG
   181  MTAYGTRRHL YDPKNHILPP MDHSTISLQM GTNKCASQVG MTAPGTRRHI YDTKLGTDKC
   241  DNSSMSLQMG YTQGANQSGQ VFGLGRQIYD PKYCPQGTVA DGAPSGTGDC PDPGEVPEYP
   301  PYYQEEAGY

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CNN2 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)
0.5
Highest tissue expression
197 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 197 nTPM
  • lymph node: 172 nTPM
  • ovary: 162 nTPM
  • tonsil: 159 nTPM
  • spleen: 149 nTPM
  • lung: 146 nTPM

Single-cell type

  • neutrophils: 590 nCPM
  • megakaryocytes: 476 nCPM
  • esophageal apical cells: 328 nCPM
  • neutrophil progenitors: 286 nCPM
  • esophageal suprabasal cells: 177 nCPM
  • epididymal basal cells: 174 nCPM

Immune cell

  • neutrophil: 848 nTPM
  • eosinophil: 632 nTPM
  • basophil: 563 nTPM
  • MAIT T-cell: 394 nTPM
  • total PBMC: 393 nTPM
  • T-reg: 348 nTPM

Brain region

  • choroid plexus: 54 nTPM
  • white matter: 19 nTPM
  • cerebral cortex: 13 nTPM
  • pons: 12 nTPM
  • medulla oblongata: 12 nTPM
  • thalamus: 11 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CNN2.

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 67 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)
0.76
gnomAD pLI
0.02
gnomAD missense Z
-0.15
DepMap mean gene effect
-0.29
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 CNN2 as an antibody target. Whether an autoantibody or antibody against CNN2 could matter depends on whether native CNN2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CNN2 is annotated at the cell surface, where native CNN2 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 CNN2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CNN2. 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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