Seroatlas · Human Serome Atlas

PLK1

Serine/threonine-protein kinase PLK1

Also known as: PLK, PLK1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P53350
Gene
PLK1
Ensembl
ENSG00000166851
Chromosome
16
Canonical length
603 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, Potential drug targets, Predicted intracellular proteins

OverviewNCBI Gene

The Ser/Thr protein kinase encoded by this gene belongs to the CDC5/Polo subfamily. It is highly expressed during mitosis and elevated levels are found in many different types of cancer. Depletion of this protein in cancer cells dramatically inhibited cell proliferation and induced apoptosis; hence, it is a target for cancer therapy. [provided by RefSeq, Sep 2015]

Canonical amino-acid sequenceUniProt

603 residues, UniProt reviewed canonical sequence.

>P53350|PLK1
     1  MSAAVTAGKL ARAPADPGKA GVPGVAAPGA PAAAPPAKEI PEVLVDPRSR RRYVRGRFLG
    61  KGGFAKCFEI SDADTKEVFA GKIVPKSLLL KPHQREKMSM EISIHRSLAH QHVVGFHGFF
   121  EDNDFVFVVL ELCRRRSLLE LHKRRKALTE PEARYYLRQI VLGCQYLHRN RVIHRDLKLG
   181  NLFLNEDLEV KIGDFGLATK VEYDGERKKT LCGTPNYIAP EVLSKKGHSF EVDVWSIGCI
   241  MYTLLVGKPP FETSCLKETY LRIKKNEYSI PKHINPVAAS LIQKMLQTDP TARPTINELL
   301  NDEFFTSGYI PARLPITCLT IPPRFSIAPS SLDPSNRKPL TVLNKGLENP LPERPREKEE
   361  PVVRETGEVV DCHLSDMLQQ LHSVNASKPS ERGLVRQEEA EDPACIPIFW VSKWVDYSDK
   421  YGLGYQLCDN SVGVLFNDST RLILYNDGDS LQYIERDGTE SYLTVSSHPN SLMKKITLLK
   481  YFRNYMSEHL LKAGANITPR EGDELARLPY LRTWFRTRSA IILHLSNGSV QINFFQDHTK
   541  LILCPLMAAV TYIDEKRDFR TYRLSLLEEY GCCKELASRL RYARTMVDKL LSSRSASNRL
   601  KAS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PLK1 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.31
Highest tissue expression
41 nTPM

Expression across tissuesHPA

Tissue

  • thymus: 41 nTPM
  • testis: 32 nTPM
  • bone marrow: 30 nTPM
  • tonsil: 28 nTPM
  • lymph node: 26 nTPM
  • esophagus: 14 nTPM

Single-cell type

  • late primary spermatocytes: 180 nCPM
  • early spermatids: 111 nCPM
  • monocyte progenitors: 108 nCPM
  • extravillous trophoblasts: 59 nCPM
  • enteric transient amplifying cells: 55 nCPM
  • migrating cytotrophoblasts: 51 nCPM

Immune cell

  • T-reg: 5.7 nTPM
  • total PBMC: 1.4 nTPM
  • memory B-cell: 1.1 nTPM
  • NK-cell: 0.9 nTPM
  • memory CD4 T-cell: 0.8 nTPM
  • neutrophil: 0.5 nTPM

Brain region

  • white matter: 1.8 nTPM
  • cerebral cortex: 1.7 nTPM
  • thalamus: 1.3 nTPM
  • cerebellum: 1.2 nTPM
  • medulla oblongata: 1 nTPM
  • amygdala: 0.9 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)
0.31
gnomAD pLI
0.98
gnomAD missense Z
2.52
DepMap mean gene effect
-2.69
DepMap dependency class
pan

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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

InteractionsUniProt · HPA

Protein binding partners of PLK1 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 PLK1 as an antibody target. Whether an autoantibody or antibody against PLK1 could matter depends on whether native PLK1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PLK1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label PLK1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PLK1. 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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