PPP2R1A
PPP2R1A (protein phosphatase 2 scaffold subunit Aalpha, also known as PR65A, PP2A-Aalpha and PP2AA) is the alpha isoform of the constant regulatory A subunit of protein phosphatase 2A. It acts as a scaffold that coordinates assembly of the catalytic subunit with a variable regulatory B subunit. Browse Assay Genie's current range of PPP2R1A research reagents below, or read on for the biology behind the target.
PPP2R1A is the PR65 subunit of protein phosphatase 2A (PP2A), one of the four major Ser/Thr phosphatases, which is implicated in the negative control of cell growth and division. The PP2A core enzyme is a heteromeric assembly of a catalytic subunit and a constant regulatory subunit, and this core associates with a variety of regulatory subunits. PPP2R1A does not act as a catalytic subunit itself. Instead it serves as the scaffold that brings the catalytic subunit and a variable regulatory B subunit together.
Through this scaffolding role the protein contributes to several processes. It is required for proper chromosome segregation and for centromeric localisation of SGO1 in mitosis, and it regulates recruitment of the SKA complex to kinetochores. With the RACK1 adapter it mediates dephosphorylation of AKT1 at Ser-473, which prevents AKT1 activation and AKT-mTOR signalling; this step is essential for regulatory T-cell homeostasis and stability. Upon interaction with GNA12 it promotes dephosphorylation of the microtubule associated protein TAU (MAPT). Within the Integrator-PP2A (INTAC) complex it acts as scaffolding subunit for PPP2CA, which dephosphorylates the C-terminal domain of POLR2A/RPB1 and SUPT5H/SPT5, preventing transcriptional elongation of unfavourably configured transcripts.
PPP2R1A is also part of striatin-interacting phosphatase and kinase (STRIPAK) complexes, which regulate pathways including Hippo, MAPK, nuclear receptor and cytoskeleton remodelling. The protein belongs to the phosphatase 2A regulatory subunit A family, and the gene was formerly named protein phosphatase 2 (formerly 2A), regulatory subunit A (PR 65), alpha isoform. Alternatively spliced transcript variants have been described. Researchers studying this PPP2R1A gene product may also work on the PPP2R1A protein in mouse, where the ortholog is Ppp2r1a.
PPP2R1A scaffolds the catalytic subunit and a variable B subunit, making it central to studies of how PP2A holoenzymes are built.
The protein is required for chromosome segregation, centromeric SGO1 localisation and SKA complex recruitment to kinetochores.
With RACK1, PPP2R1A dephosphorylates AKT1 at Ser-473, a step essential for regulatory T-cell homeostasis and stability.
PPP2R1A functions in the INTAC transcription checkpoint and in STRIPAK complexes that regulate Hippo, MAPK and cytoskeletal pathways.
PPP2R1A is the scaffolding A subunit of protein phosphatase 2A. It coordinates assembly of the catalytic subunit with a variable regulatory B subunit. It also supports chromosome segregation, AKT1 dephosphorylation, STRIPAK complexes and the INTAC transcription elongation checkpoint.
PPP2R1A is also called PR65A, PP2A-Aalpha and PP2AA. Its UniProt name is serine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A alpha isoform, and an earlier gene name was protein phosphatase 2 (formerly 2A), regulatory subunit A (PR 65), alpha isoform. Alternatively spliced transcript variants have been described.
A mouse ortholog, Ppp2r1a, is recorded for this gene. The alpha isoform is one of the constant regulatory A subunits of PP2A. Check the datasheet of any product for its validated reactivity.
Other PP2A subunits, related Ser/Thr protein phosphatases and their regulatory partners with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P30153; product specifications from Assay Genie datasheets.