Seroatlas · Human Serome Atlas

PLK3

Serine/threonine-protein kinase PLK3

Also known as: CNK, FNK, PLK3_HUMAN, PRK

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

Protein identityUniProt · HPA

UniProt accession
Q9H4B4
Gene
PLK3
Ensembl
ENSG00000173846
Chromosome
1
Canonical length
646 aa
Protein class
Enzymes, Predicted intracellular proteins

OverviewNCBI Gene

The protein encoded by this gene is a member of the highly conserved polo-like kinase family of serine/threonine kinases. Members of this family are characterized by an amino-terminal kinase domain and a carboxy-terminal bipartite polo box domain that functions as a substrate-binding motif and a cellular localization signal. Polo-like kinases are important regulators of cell cycle progression. This gene has also been implicated in stress responses and double-strand break repair. In human cell lines, this protein is reported to associate with centrosomes in a microtubule-dependent manner, and during mitosis, the protein becomes localized to the mitotic apparatus. Expression of a kinase-defective mutant results in abnormal cell morphology caused by changes in microtubule dynamics and mitotic arrest followed by apoptosis. [provided by RefSeq, Sep 2015]

Canonical amino-acid sequenceUniProt

646 residues, UniProt reviewed canonical sequence.

>Q9H4B4|PLK3
     1  MEPAAGFLSP RPFQRAAAAP APPAGPGPPP SALRGPELEM LAGLPTSDPG RLITDPRSGR
    61  TYLKGRLLGK GGFARCYEAT DTETGSAYAV KVIPQSRVAK PHQREKILNE IELHRDLQHR
   121  HIVRFSHHFE DADNIYIFLE LCSRKSLAHI WKARHTLLEP EVRYYLRQIL SGLKYLHQRG
   181  ILHRDLKLGN FFITENMELK VGDFGLAARL EPPEQRKKTI CGTPNYVAPE VLLRQGHGPE
   241  ADVWSLGCVM YTLLCGSPPF ETADLKETYR CIKQVHYTLP ASLSLPARQL LAAILRASPR
   301  DRPSIDQILR HDFFTKGYTP DRLPISSCVT VPDLTPPNPA RSLFAKVTKS LFGRKKKSKN
   361  HAQERDEVSG LVSGLMRTSV GHQDARPEAP AASGPAPVSL VETAPEDSSP RGTLASSGDG
   421  FEEGLTVATV VESALCALRN CIAFMPPAEQ NPAPLAQPEP LVWVSKWVDY SNKFGFGYQL
   481  SSRRVAVLFN DGTHMALSAN RKTVHYNPTS TKHFSFSVGA VPRALQPQLG ILRYFASYME
   541  QHLMKGGDLP SVEEVEVPAP PLLLQWVKTD QALLMLFSDG TVQVNFYGDH TKLILSGWEP
   601  LLVTFVARNR SACTYLASHL RQLGCSPDLR QRLRYALRLL RDRSPA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PLK3 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)
0.35
Highest tissue expression
20 nTPM

Expression across tissuesHPA

Tissue

  • blood vessel: 20 nTPM
  • esophagus: 20 nTPM
  • skin: 18 nTPM
  • urinary bladder: 17 nTPM
  • gallbladder: 16 nTPM
  • adipose tissue: 15 nTPM

Single-cell type

  • esophageal apical cells: 392 nCPM
  • neutrophils: 325 nCPM
  • epididymal principal cells: 122 nCPM
  • breast lactating cells: 111 nCPM
  • esophageal basal cells: 104 nCPM
  • esophageal suprabasal cells: 98 nCPM

Immune cell

  • T-reg: 14 nTPM
  • naive CD4 T-cell: 13 nTPM
  • memory CD4 T-cell: 12 nTPM
  • non-classical monocyte: 6.3 nTPM
  • intermediate monocyte: 5.9 nTPM
  • naive CD8 T-cell: 5.8 nTPM

Brain region

  • medulla oblongata: 19 nTPM
  • choroid plexus: 16 nTPM
  • white matter: 14 nTPM
  • midbrain: 14 nTPM
  • pons: 13 nTPM
  • hypothalamus: 12 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)
0.71
gnomAD pLI
0
gnomAD missense Z
1.24
DepMap mean gene effect
-0.07
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

InteractionsUniProt · HPA

Protein binding partners of PLK3 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 PLK3 as an antibody target. Whether an autoantibody or antibody against PLK3 could matter depends on whether native PLK3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PLK3 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 PLK3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PLK3. 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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