Seroatlas · Human Serome Atlas

POLR2M

DNA-directed RNA polymerase II subunit GRINL1A

Also known as: Gdown, Gdown1, GRINL1A, GRL1A_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P0CAP2
Gene
POLR2M
Ensembl
ENSG00000255529
Chromosome
15
Canonical length
368 aa
Protein class
Predicted intracellular proteins, RNA polymerase related proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

This gene encodes a subunit of a specific form of RNA polymerase II termed Pol II(G). The encoded protein may act as a negative regulator of transcriptional activation by the Mediator complex. Alternative splicing results in multiple transcript variants. There is a pseudogene for this gene on chromosome 4. Readthrough transcription between this gene and the neighboring upstream gene MYZAP (myocardial zonula adherens protein) is represented with GeneID 145781. [provided by RefSeq, Oct 2013]

Canonical amino-acid sequenceUniProt

368 residues, UniProt reviewed canonical sequence.

>P0CAP2|POLR2M
     1  MCSLPRGFEP QAPEDLAQRS LVELREMLKR QERLLRNEKF ICKLPDKGKK IFDSFAKLKA
    61  AIAECEEVRR KSELFNPVSL DCKLRQKAIA EVDVGTDKAQ NSDPILDTSS LVPGCSSVDN
   121  IKSSQTSQNQ GLGRPTLEGD EETSEVEYTV NKGPASSNRD RVPPSSEASE HHPRHRVSSQ
   181  AEDTSSSFDN LFIDRLQRIT IADQGEQQSE ENASTKNLTG LSSGTEKKPH YMEVLEMRAK
   241  NPVPQLRKFK TNVLPFRQND SSSHCQKSGS PISSEERRRR DKQHLDDITA ARLLPLHHMP
   301  TQLLSIEESL ALQKQQKQNY EEMQAKLAAQ KLAERLNIKM RSYNPEGESS GRYREVRDED
   361  DDWSSDEF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against POLR2M 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)
0.62
Highest tissue expression
36 nTPM

Expression across tissuesHPA

Tissue

  • tongue: 36 nTPM
  • skeletal muscle: 34 nTPM
  • endometrium: 32 nTPM
  • blood vessel: 29 nTPM
  • ovary: 28 nTPM
  • heart muscle: 27 nTPM

Single-cell type

  • oocytes: 65 nCPM
  • endometrial glandular cells: 49 nCPM
  • late primary spermatocytes: 48 nCPM
  • epididymal clear cells: 47 nCPM
  • kupffer cells: 43 nCPM
  • smooth muscle cells: 39 nCPM

Immune cell

  • basophil: 27 nTPM
  • NK-cell: 25 nTPM
  • naive CD4 T-cell: 20 nTPM
  • T-reg: 19 nTPM
  • gdT-cell: 18 nTPM
  • naive B-cell: 17 nTPM

Brain region

  • midbrain: 87 nTPM
  • white matter: 85 nTPM
  • basal ganglia: 77 nTPM
  • spinal cord: 74 nTPM
  • medulla oblongata: 74 nTPM
  • thalamus: 74 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)
0.73
gnomAD pLI
0.03
gnomAD missense Z
-0.85
DepMap mean gene effect
-0.36
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads POLR2M as an antibody target. Whether an autoantibody or antibody against POLR2M could matter depends on whether native POLR2M is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

POLR2M 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 POLR2M as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/POLR2M. 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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