Seroatlas · Human Serome Atlas

PPP1R8

Nuclear inhibitor of protein phosphatase 1

Also known as: ard-1, ARD1, NIPP-1, NIPP1, PP1R8_HUMAN, PRO2047

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

Protein identityUniProt · HPA

UniProt accession
Q12972
Gene
PPP1R8
Ensembl
ENSG00000117751
Chromosome
1
Canonical length
351 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Nuclear speckles

OverviewNCBI Gene

This gene, through alternative splicing, encodes three different isoforms. Two of the protein isoforms encoded by this gene are specific inhibitors of type 1 serine/threonine protein phosphatases and can bind but not cleave RNA. The third protein isoform lacks the phosphatase inhibitory function but is a single-strand endoribonuclease comparable to RNase E of E. coli. This isoform requires magnesium for its function and cleaves specific sites in A+U-rich regions of RNA. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

351 residues, UniProt reviewed canonical sequence.

>Q12972|PPP1R8
     1  MAAAANSGSS LPLFDCPTWA GKPPPGLHLD VVKGDKLIEK LIIDEKKYYL FGRNPDLCDF
    61  TIDHQSCSRV HAALVYHKHL KRVFLIDLNS THGTFLGHIR LEPHKPQQIP IDSTVSFGAS
   121  TRAYTLREKP QTLPSAVKGD EKMGGEDDEL KGLLGLPEEE TELDNLTEFN TAHNKRISTL
   181  TIEEGNLDIQ RPKRKRKNSR VTFSEDDEII NPEDVDPSVG RFRNMVQTAV VPVKKKRVEG
   241  PGSLGLEESG SRRMQNFAFS GGLYGGLPPT HSEAGSQPHG IHGTALIGGL PMPYPNLAPD
   301  VDLTPVVPSA VNMNPAPNPA VYNPEAVNEP KKKKYAKEAW PGKKPTPSLL I

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PPP1R8 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)
0.55
Highest tissue expression
38 nTPM

Expression across tissuesHPA

Tissue

  • thymus: 38 nTPM
  • bone marrow: 37 nTPM
  • tongue: 35 nTPM
  • tonsil: 34 nTPM
  • ovary: 34 nTPM
  • lymph node: 33 nTPM

Single-cell type

  • cytotrophoblasts: 60 nCPM
  • oocytes: 60 nCPM
  • syncytiotrophoblasts: 56 nCPM
  • migrating cytotrophoblasts: 55 nCPM
  • differentiating spermatogonia: 54 nCPM
  • extravillous trophoblasts: 54 nCPM

Immune cell

  • basophil: 17 nTPM
  • MAIT T-cell: 14 nTPM
  • NK-cell: 14 nTPM
  • memory CD8 T-cell: 14 nTPM
  • total PBMC: 13 nTPM
  • gdT-cell: 12 nTPM

Brain region

  • white matter: 43 nTPM
  • basal ganglia: 35 nTPM
  • spinal cord: 35 nTPM
  • cerebellum: 35 nTPM
  • medulla oblongata: 34 nTPM
  • hypothalamus: 33 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)
0.22
gnomAD pLI
0.99
gnomAD missense Z
2.91
DepMap mean gene effect
-1.11
DepMap dependency class
common

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 PPP1R8 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 PPP1R8 as an antibody target. Whether an autoantibody or antibody against PPP1R8 could matter depends on whether native PPP1R8 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PPP1R8 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 PPP1R8 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PPP1R8. 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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