Seroatlas · Human Serome Atlas

OPTC

Opticin

Also known as: OPT_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9UBM4
Gene
OPTC
Ensembl
ENSG00000188770
Chromosome
1
Canonical length
332 aa
Protein class
Predicted secreted proteins
Secretome location
Secreted in other tissues
Quaternary structure
Homodimer

OverviewNCBI Gene

Opticin belongs to class III of the small leucine-rich repeat protein (SLRP) family. Members of this family are typically associated with the extracellular matrix. Opticin is present in significant quantities in the vitreous of the eye and also localizes to the cornea, iris, ciliary body, optic nerve, choroid, retina, and fetal liver. Opticin may noncovalently bind collagen fibrils and regulate fibril morphology, spacing, and organization. The opticin gene is mapped to a region of chromosome 1 that is associated with the inherited eye diseases age-related macular degeneration (AMD) and posterior column ataxia with retinosa pigmentosa (AXPC1). [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

332 residues, UniProt reviewed canonical sequence.

>Q9UBM4|OPTC
     1  MRLLAFLSLL ALVLQETGTA SLPRKERKRR EEQMPREGDS FEVLPLRNDV LNPDNYGEVI
    61  DLSNYEELTD YGDQLPEVKV TSLAPATSIS PAKSTTAPGT PSSNPTMTRP TTAGLLLSSQ
   121  PNHGLPTCLV CVCLGSSVYC DDIDLEDIPP LPRRTAYLYA RFNRISRIRA EDFKGLTKLK
   181  RIDLSNNLIS SIDNDAFRLL HALQDLILPE NQLEALPVLP SGIEFLDVRL NRLQSSGIQP
   241  AAFRAMEKLQ FLYLSDNLLD SIPGPLPLSL RSVHLQNNLI ETMQRDVFCD PEEHKHTRRQ
   301  LEDIRLDGNP INLSLFPSAY FCLPRLPIGR FT

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against OPTC 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)
0.44
Highest tissue expression
0.6 nTPM

Expression across tissuesHPA

Tissue

  • retina: 0.6 nTPM
  • testis: 0.4 nTPM
  • colon: 0.2 nTPM
  • endometrium: 0.2 nTPM
  • epididymis: 0.2 nTPM
  • cerebral cortex: 0.1 nTPM

Single-cell type

  • epicardial cells: 21 nCPM
  • retinal bipolar cells: 4 nCPM
  • cardiomyocytes: 3.2 nCPM
  • endometrial glandular cells: 3 nCPM
  • lacrimal acinar cells: 2.7 nCPM
  • schwann cells: 2.2 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • pons: 1.8 nTPM
  • medulla oblongata: 1.7 nTPM
  • midbrain: 1.5 nTPM
  • thalamus: 1.4 nTPM
  • amygdala: 1.2 nTPM
  • basal ganglia: 1.2 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)
1.81
gnomAD pLI
0
gnomAD missense Z
-0.53
DepMap mean gene effect
-0.04
DepMap dependency class
none

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

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

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