Seroatlas · Human Serome Atlas

PPP2R1B

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

Also known as: 2AAB_HUMAN, PP2A-Abeta, PR65B

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

Protein identityUniProt · HPA

UniProt accession
P30154
Gene
PPP2R1B
Ensembl
ENSG00000137713
Chromosome
11
Canonical length
601 aa
Protein class
Human disease related genes, Predicted intracellular proteins
Subcellular location
Plasma membrane,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 a beta isoform of the constant regulatory subunit A. Mutations in this gene have been associated with some lung and colon cancers. Alternatively spliced transcript variants have been described. [provided by RefSeq, Apr 2010]

Canonical amino-acid sequenceUniProt

601 residues, UniProt reviewed canonical sequence.

>P30154|PPP2R1B
     1  MAGASELGTG PGAAGGDGDD SLYPIAVLID ELRNEDVQLR LNSIKKLSTI ALALGVERTR
    61  SELLPFLTDT IYDEDEVLLA LAEQLGNFTG LVGGPDFAHC LLPPLENLAT VEETVVRDKA
   121  VESLRQISQE HTPVALEAYF VPLVKRLASG DWFTSRTSAC GLFSVCYPRA SNAVKAEIRQ
   181  QFRSLCSDDT PMVRRAAASK LGEFAKVLEL DSVKSEIVPL FTSLASDEQD SVRLLAVEAC
   241  VSIAQLLSQD DLETLVMPTL RQAAEDKSWR VRYMVADRFS ELQKAMGPKI TLNDLIPAFQ
   301  NLLKDCEAEV RAAAAHKVKE LGENLPIEDR ETIIMNQILP YIKELVSDTN QHVKSALASV
   361  IMGLSTILGK ENTIEHLLPL FLAQLKDECP DVRLNIISNL DCVNEVIGIR QLSQSLLPAI
   421  VELAEDAKWR VRLAIIEYMP LLAGQLGVEF FDEKLNSLCM AWLVDHVYAI REAATNNLMK
   481  LVQKFGTEWA QNTIVPKVLV MANDPNYLHR MTTLFCINAL SEACGQEITT KQMLPIVLKM
   541  AGDQVANVRF NVAKSLQKIG PILDTNALQG EVKPVLQKLG QDEDMDVKYF AQEAISVLAL
   601  A

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PPP2R1B 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)
0.24
Highest tissue expression
153 nTPM

Expression across tissuesHPA

Tissue

  • liver: 153 nTPM
  • adipose tissue: 55 nTPM
  • testis: 51 nTPM
  • pancreas: 31 nTPM
  • stomach: 21 nTPM
  • breast: 20 nTPM

Single-cell type

  • adipocytes: 703 nCPM
  • late primary spermatocytes: 360 nCPM
  • early spermatids: 288 nCPM
  • late spermatids: 218 nCPM
  • endometrial glandular cells: 124 nCPM
  • hepatocytes: 120 nCPM

Immune cell

  • NK-cell: 15 nTPM
  • T-reg: 15 nTPM
  • myeloid DC: 15 nTPM
  • gdT-cell: 13 nTPM
  • memory CD4 T-cell: 13 nTPM
  • MAIT T-cell: 13 nTPM

Brain region

  • white matter: 44 nTPM
  • cerebellum: 44 nTPM
  • basal ganglia: 40 nTPM
  • choroid plexus: 39 nTPM
  • medulla oblongata: 35 nTPM
  • cerebral cortex: 33 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about PPP2R1B.

Disease | GeneticClinVar

1 pathogenic / likely-pathogenic of 118 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Lung carcinoma

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)
1.06
gnomAD pLI
0
gnomAD missense Z
1.07
DepMap mean gene effect
0.12
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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 PPP2R1B 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 PPP2R1B as an antibody target. Whether an autoantibody or antibody against PPP2R1B could matter depends on whether native PPP2R1B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PPP2R1B is annotated at the cell surface, where native PPP2R1B 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 PPP2R1B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PPP2R1B. 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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