Recombinant Human Serine/threonine-protein phosphatase 2A 55 kDa regulatory subunit B beta isoform (PPP2R2B)

Function

The B regulatory subunit might modulate substrate selectivity and catalytic activity, and might also direct the localization of the catalytic enzyme to a particular subcellular compartment. Within the PP2A holoenzyme complex, isoform 2 is required to promote proapoptotic activity (By similarity). Isoform 2 regulates neuronal survival through the mitochondrial fission and fusion balance (By similarity)

Subcellular Location

Cytoplasm; Mitochondrion; Mitochondrion outer membrane

Disease Association

Spinocerebellar ataxia 12 (SCA12) : Spinocerebellar ataxia is a clinically and genetically heterogeneous group of cerebellar disorders. Patients show progressive incoordination of gait and often poor coordination of hands, speech and eye movements, due to degeneration of the cerebellum with variable involvement of the brainstem and spinal cord. SCA12 is an autosomal dominant cerebellar ataxia (ADCA). [The disease is caused by variants affecting the gene represented in this entry]

Tissue Specificity

Brain

Subunit

PP2A consists of a common heterodimeric core enzyme, composed of a 36 kDa catalytic subunit (subunit C) and a 65 kDa constant regulatory subunit (PR65 or subunit A), that associates with a variety of regulatory subunits. Proteins that associate with the core dimer include three families of regulatory subunits B (the R2/B/PR55/B55, R3/B''/PR72/PR130/PR59 and R5/B'/B56 families), the 48 kDa variable regulatory subunit, viral proteins, and cell signaling molecules (By similarity). Interacts with TOMM22 (By similarity). Interacts with IER5 (via N- and C-terminal regions) (PubMed:25816751, PubMed:26496226)

• Mayer R.E. et al. Structure of the 55-kDa regulatory subunit of protein phosphatase 2A: evidence for a neuronal-specific isoform. — Biochemistry (1991)
• Ota T. et al. Complete sequencing and characterization of 21,243 full-length human cDNAs. — Nat. Genet. (2004)
• Schmutz J. et al. The DNA sequence and comparative analysis of human chromosome 5. — Nature (2004)
• Mural R.J. et al. PubMed: CI-5GBD0VIIJ7C63 (SEP-)
• The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). — Genome Res. (2004)
• Strausberg R.L. et al. PubMed: CI-CL47BJI4CL4IQ (AUG-)
• Holmes S.E. et al. Expansion of a novel CAG trinucleotide repeat in the 5' region of PPP2R2B is associated with SCA12. — Nat. Genet. (1999)
• Ishikawa Y. et al. HSF1 transcriptional activity is modulated by IER5 and PP2A/B55. — FEBS Lett. (2015)