Seroatlas · Human Serome Atlas

PPP2R1A

Serine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A alpha isoform

Also known as: 2AAA_HUMAN, PP2A-Aalpha, PP2AA, PR65A

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

Protein identityUniProt · HPA

UniProt accession
P30153
Gene
PPP2R1A
Ensembl
ENSG00000105568
Chromosome
19
Canonical length
589 aa
Protein class
Cancer-related genes, Disease related genes, Human disease related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

This gene encodes a constant regulatory subunit of protein phosphatase 2. Protein phosphatase 2 is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The constant regulatory subunit A serves as a scaffolding molecule to coordinate the assembly of the catalytic subunit and a variable regulatory B subunit. This gene encodes an alpha isoform of the constant regulatory subunit A. Alternatively spliced transcript variants have been described. [provided by RefSeq, Apr 2010]

Canonical amino-acid sequenceUniProt

589 residues, UniProt reviewed canonical sequence.

>P30153|PPP2R1A
     1  MAAADGDDSL YPIAVLIDEL RNEDVQLRLN SIKKLSTIAL ALGVERTRSE LLPFLTDTIY
    61  DEDEVLLALA EQLGTFTTLV GGPEYVHCLL PPLESLATVE ETVVRDKAVE SLRAISHEHS
   121  PSDLEAHFVP LVKRLAGGDW FTSRTSACGL FSVCYPRVSS AVKAELRQYF RNLCSDDTPM
   181  VRRAAASKLG EFAKVLELDN VKSEIIPMFS NLASDEQDSV RLLAVEACVN IAQLLPQEDL
   241  EALVMPTLRQ AAEDKSWRVR YMVADKFTEL QKAVGPEITK TDLVPAFQNL MKDCEAEVRA
   301  AASHKVKEFC ENLSADCREN VIMSQILPCI KELVSDANQH VKSALASVIM GLSPILGKDN
   361  TIEHLLPLFL AQLKDECPEV RLNIISNLDC VNEVIGIRQL SQSLLPAIVE LAEDAKWRVR
   421  LAIIEYMPLL AGQLGVEFFD EKLNSLCMAW LVDHVYAIRE AATSNLKKLV EKFGKEWAHA
   481  TIIPKVLAMS GDPNYLHRMT TLFCINVLSE VCGQDITTKH MLPTVLRMAG DPVANVRFNV
   541  AKSLQKIGPI LDNSTLQSEV KPILEKLTQD QDVDVKYFAQ EALTVLSLA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PPP2R1A 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
Cell surface
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.23
Highest tissue expression
310 nTPM

Expression across tissuesHPA

Tissue

  • heart muscle: 310 nTPM
  • adrenal gland: 300 nTPM
  • hippocampal formation: 297 nTPM
  • basal ganglia: 272 nTPM
  • cerebral cortex: 258 nTPM
  • amygdala: 247 nTPM

Single-cell type

  • esophageal apical cells: 661 nCPM
  • extravillous trophoblasts: 342 nCPM
  • migrating cytotrophoblasts: 274 nCPM
  • esophageal suprabasal cells: 266 nCPM
  • decidual stromal cells: 258 nCPM
  • cytotrophoblasts: 250 nCPM

Immune cell

  • total PBMC: 296 nTPM
  • NK-cell: 255 nTPM
  • intermediate monocyte: 237 nTPM
  • non-classical monocyte: 228 nTPM
  • myeloid DC: 225 nTPM
  • T-reg: 206 nTPM

Brain region

  • hippocampal formation: 331 nTPM
  • thalamus: 305 nTPM
  • cerebral cortex: 293 nTPM
  • pons: 254 nTPM
  • basal ganglia: 248 nTPM
  • amygdala: 240 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about PPP2R1A.

Disease | AllUniProt

Conditions PPP2R1A is implicated in, by any mechanism.

Disease | GeneticClinVar

20 pathogenic / likely-pathogenic of 642 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.3
gnomAD pLI
0.98
gnomAD missense Z
4.46
DepMap mean gene effect
-0.86
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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 PPP2R1A 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 PPP2R1A as an antibody target. Whether an autoantibody or antibody against PPP2R1A could matter depends on whether native PPP2R1A is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PPP2R1A is annotated at the cell surface, where native PPP2R1A is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label PPP2R1A as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PPP2R1A. 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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