Seroatlas · Human Serome Atlas

GKN1

Gastrokine-1

Also known as: AMP18, BRICD1, CA11, GKN1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9NS71
Gene
GKN1
Ensembl
ENSG00000169605
Chromosome
2
Canonical length
185 aa
Protein class
Plasma proteins, Predicted secreted proteins, Transporters
Secretome location
Secreted to digestive system

OverviewNCBI Gene

The protein encoded by this gene is found to be down-regulated in human gastric cancer tissue as compared to normal gastric mucosa. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

185 residues, UniProt reviewed canonical sequence.

>Q9NS71|GKN1
     1  MKFTIVFAGL LGVFLAPALA NYNINVNDDN NNAGSGQQSV SVNNEHNVAN VDNNNGWDSW
    61  NSIWDYGNGF AATRLFQKKT CIVHKMNKEV MPSIQSLDAL VKEKKLQGKG PGGPPPKGLM
   121  YSVNPNKVDD LSKFGKNIAN MCRGIPTYMA EEMQEASLFF YSGTCYTTSV LWIVDISFCG
   181  DTVEN

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against GKN1 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)
0.34
Highest tissue expression
35,311 nTPM

Expression across tissuesHPA

Tissue

  • stomach: 35,311 nTPM
  • placenta: 19 nTPM
  • spleen: 9.8 nTPM
  • pancreas: 4.6 nTPM
  • esophagus: 3.4 nTPM
  • lung: 3.3 nTPM

Single-cell type

  • foveolar cells: 48,851 nCPM
  • mucous neck cells: 325 nCPM
  • gastric chief cells: 210 nCPM
  • parietal cells: 35 nCPM
  • neuroendocrine cells: 18 nCPM
  • nk-cells: 18 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

  • amygdala: 0 nTPM
  • basal ganglia: 0 nTPM
  • cerebellum: 0 nTPM
  • cerebral cortex: 0 nTPM
  • choroid plexus: 0 nTPM
  • hippocampal formation: 0 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)
1.7
gnomAD pLI
0
gnomAD missense Z
0.8
DepMap mean gene effect
0.16
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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 GKN1 as an antibody target. Whether an autoantibody or antibody against GKN1 could matter depends on whether native GKN1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

GKN1 is annotated as secreted, so native GKN1 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 GKN1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/GKN1. 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).

© 2026 · Seroatlas, Discover Oregon LLC · Terms of use

Loading the interactive Seroatlas protein explorer...