PI3K/Akt/mTOR · target hub

PPP2R1B

Serine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A beta isoform (PPP2R1B)

PPP2R1B is a PIP₃ / Akt phosphatase or PP2A regulation on the PI3K/Akt/mTOR axis. The PR65 subunit of protein phosphatase 2A serves as a scaffolding molecule to coordinate the assembly of the catalytic subunit and a variable regulatory B subunit It is indexed under "Akt / mTOR-directed phosphatases & PP2A subunits (selected)" on our pathway page for antibodies, inhibitors, and assay guidance.

Back to pathway overviewSearch: PPP2R1BUniProt (P30154)

Research notes

  • Combine with other genes in the same hub block via genetics or pharmacology to test non-redundant roles of PPP2R1B.
  • Annotate PIK3CA/PTEN and upstream RTK–Ras context when reading p-AKT, mTORC1/2, or lipid outputs.
  • Verify antibody clone, phospho-site, and stimulation; include KD/KO or inhibitor controls.

On the pathway hub (sections)

Genetic lesions & expression context (quick reference)

Type / exampleDomain / context (brief)
Expression contextTissue/cell-type–dependent expression
Rare variantsSporadic variants—require functional validation
Pathway couplingCo-occurs with neighboring nodes on the hub

Naming and prevalence vary by cohort and assay—annotate clinically with COSMIC, ClinVar, OncoKB, and datasheets; research context only.

Assay readouts for PPP2R1B

  • Lipid pools: PIP₃, PI(3,4)P₂, or substrates relevant to PPP2R1B.
  • Loss-of-function: CRISPR/siRNA often elevates p-AKT and growth readouts (context-dependent).
  • Tumor specimens: matched tumor/adjacent with mutation/expression annotation.
  • Inhibitor controls: PI3K/mTOR inhibitors to test phenotypic reversibility.

PPP2R1B experimental notes

Examples below reflect common literature and public resources (e.g., CCLE, DepMap)—validate genotypes, expression, and passage in your own stocks before committing assays.

[1] Cell lines commonly used for PPP2R1B studies (examples)

  • Tool lines: MCF-7, U87, PC-3, HEK293T, A549—screen by PPP2R1B expression and pathway context (CCLE/DepMap).
  • Combine with neighbors (PHLPP1, PHLPP2, PPP2CA, PPP2CB) via KD/pharmacology to test non-redundancy.
  • Overexpression/rescue in HEK293T supports mechanism and IP workflows.
  • Isogenic/CRISPR models separate pathway dependency from bypass survival.

[2] Cell samples for PPP2R1B Western blot

  • Whole-cell lysates—optimize RIPA/NP-40 per antibody; phosphatase inhibitors for phospho blots.
  • Stimulation: serum starvation ± insulin/EGF or amino-acid withdrawal/refeed as relevant.
  • Controls: siRNA/shRNA, CRISPR KO, or inhibitors to validate band specificity.
  • Loading: BCA normalization; subcellular fractionation when needed.

[3] Tissue samples for PPP2R1B Western blot

  • Matched tumor/adjacent frozen tissues after pathology review.
  • Mouse GEMM or xenografts—mind species antibody cross-reactivity.
  • Primary cells/PDCs when ethically approved.
  • FFPE needs specialized extraction; frozen tissue preferred for phospho work.

[4] Cell samples for PPP2R1B immunoprecipitation

  • Tagged overexpression: HEK293T FLAG/HA-PPP2R1B for complex capture.
  • Endogenous IP: high-expression lines; often ≥1–5×10⁶ cells per IP.
  • Stimulation: ligand or nutrient treatments enrich interactions—pilot time courses.
  • Controls: isotype IgG, empty vector, KD/KO negatives.

Human tissues and primary cells require ethics/IRB approval; tumors are heterogeneous—record histotype, site, and preservation conditions.

Bypass & related pathways

Models & genetics note

Overexpression vs endogenous PPP2R1B can differ in dosage, splicing, and compartmentation—in organoids/PDX, record passage, matrix, and drug history.

Quick search presets

PPP2R1BPPP2R1B antibodyPI3K inhibitormTOR inhibitor

PPP2R1B-related antibodies (keyword-biased)

Adds PPP2R1B keyword bias atop the PI3K/Akt/mTOR antibody pool—if sparse, use presets above or global search.

Neighboring targets (same hub)

PHLPP1PHLPP2PPP2CAPPP2CBPPP2R1APPP2R2APPP2R2BPPP2R2C

External databases & resources

FAQ

This content supports research reagents and pathway education—not medical advice. Annotate mutations, drug indications, and protocols with authoritative databases, datasheets, and institutional oversight.

Last reviewed: 2026-05-18

Related on this site

See the PI3K/Akt/mTOR hub for neighboring nodes and assay guidance—cross-check MAPK, RTK, metabolism, and autophagy pages as needed.

PI3K/Akt/mTOR·MAPK/ERK·Receptor tyrosine kinase·Metabolism