Seroatlas · Human Serome Atlas

KNG1

Kininogen-1

Also known as: BDK, BK, HK, HMWK, KNG, KNG1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P01042
Gene
KNG1
Ensembl
ENSG00000113889
Chromosome
3
Canonical length
644 aa
Protein class
Disease related genes, Human disease related genes, Plasma proteins, Predicted secreted proteins
Secretome location
Secreted to blood

OverviewNCBI Gene

This gene uses alternative splicing to generate two different proteins- high molecular weight kininogen (HMWK) and low molecular weight kininogen (LMWK). HMWK is essential for blood coagulation and assembly of the kallikrein-kinin system. Also, bradykinin, a peptide causing numerous physiological effects, is released from HMWK. Bradykinin also functions as an antimicrobial peptide with antibacterial and antifungal activity. In contrast to HMWK, LMWK is not involved in blood coagulation. Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reduces or depletes angiotensin converting enzyme 2 (ACE2), which results in an increase in levels of des-Arg(9)-bradykinin, a bioactive metabolite of bradykinin that is associated with lung injury and inflammation. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2020]

Canonical amino-acid sequenceUniProt

644 residues, UniProt reviewed canonical sequence.

>P01042|KNG1
     1  MKLITILFLC SRLLLSLTQE SQSEEIDCND KDLFKAVDAA LKKYNSQNQS NNQFVLYRIT
    61  EATKTVGSDT FYSFKYEIKE GDCPVQSGKT WQDCEYKDAA KAATGECTAT VGKRSSTKFS
   121  VATQTCQITP AEGPVVTAQY DCLGCVHPIS TQSPDLEPIL RHGIQYFNNN TQHSSLFMLN
   181  EVKRAQRQVV AGLNFRITYS IVQTNCSKEN FLFLTPDCKS LWNGDTGECT DNAYIDIQLR
   241  IASFSQNCDI YPGKDFVQPP TKICVGCPRD IPTNSPELEE TLTHTITKLN AENNATFYFK
   301  IDNVKKARVQ VVAGKKYFID FVARETTCSK ESNEELTESC ETKKLGQSLD CNAEVYVVPW
   361  EKKIYPTVNC QPLGMISLMK RPPGFSPFRS SRIGEIKEET TVSPPHTSMA PAQDEERDSG
   421  KEQGHTRRHD WGHEKQRKHN LGHGHKHERD QGHGHQRGHG LGHGHEQQHG LGHGHKFKLD
   481  DDLEHQGGHV LDHGHKHKHG HGHGKHKNKG KKNGKHNGWK TEHLASSSED STTPSAQTQE
   541  KTEGPTPIPS LAKPGVTVTF SDFQDSDLIA TMMPPISPAP IQSDDDWIPD IQIDPNGLSF
   601  NPISDFPDTT SPKCPGRPWK SVSEINPTTQ MKESYYFDLT DGLS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KNG1 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)
0.49
Highest tissue expression
2,986 nTPM

Expression across tissuesHPA

Tissue

  • liver: 2,986 nTPM
  • kidney: 433 nTPM
  • rectum: 0.9 nTPM
  • colon: 0.8 nTPM
  • cerebral cortex: 0.4 nTPM
  • placenta: 0.4 nTPM

Single-cell type

  • hepatocytes: 2,201 nCPM
  • distal convoluted tubule cells: 648 nCPM
  • loop of henle epithelial cells: 131 nCPM
  • renal connecting tubule cells: 108 nCPM
  • cholangiocytes: 36 nCPM
  • kupffer cells: 25 nCPM

Immune cell

  • basophil: 0.4 nTPM
  • neutrophil: 0.2 nTPM
  • NK-cell: 0.1 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM

Brain region

  • cerebral cortex: 1 nTPM
  • cerebellum: 0.5 nTPM
  • white matter: 0.5 nTPM
  • basal ganglia: 0.4 nTPM
  • medulla oblongata: 0.4 nTPM
  • midbrain: 0.4 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about KNG1.

Disease | AllUniProt

Conditions KNG1 is implicated in, by any mechanism.

  • High molecular weight kininogen deficiency (HMWK deficiency) MIM:228960
  • Angioedema, hereditary, 6 (HAE6) MIM:619363

Disease | GeneticClinVar

9 pathogenic / likely-pathogenic of 149 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • High molecular weight kininogen deficiency
  • Angioedema, hereditary, 6
  • KININOGEN DEFICIENCY, TOTAL

Disease | ImmuneIEDB

Conditions an epitope on KNG1 was assayed in.

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)
0.92
gnomAD pLI
0
gnomAD missense Z
-0.11
DepMap mean gene effect
-0.03
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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 KNG1 as an antibody target. Whether an autoantibody or antibody against KNG1 could matter depends on whether native KNG1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KNG1 is annotated as secreted, so native KNG1 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 KNG1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KNG1. 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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