PPP2R2B Antibody – Rabbit Polyclonal

The product of this gene belongs to the phosphatase 2 regulatory subunit B family. 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 B regulatory subunit might modulate substrate selectivity and catalytic activity. This gene encodes a beta isoform of the regulatory subunit B55 subfamily. Defects in this gene cause autosomal dominant spinocerebellar ataxia 12 (SCA12), a disease caused by degeneration of the cerebellum, sometimes involving the brainstem and spinal cord, and in resulting in poor coordination of speech and body movements. Multiple alternatively spliced variants, which encode different isoforms, have been identified for this gene. The 5' UTR of some of these variants includes a CAG trinucleotide repeat sequence (7-28 copies) that can be expanded to 55-78 copies in cases of SCA12. [provided by RefSeq, Jul 2016]

PPP2R2B: the B regulatory subunit of PP2A. May modulate substrate selectivity and catalytic activity, and directs the localization of the catalytic enzyme to particular subcellular compartments. PPP2R2B promotes autophagy and oxidative stress induced cell death that is related to apoptosis. The PP2A holoenzyme consists of a common heterodimeric core enzyme composed of a 36 kDa catalytic subunit (subunit C) and a 65 kDa constant regulatory subunit (subunit A), that associates with a variety of regulatory subunits. Three families of regulatory subunits associate with the core dimmer: B (R2/PR55/B55), B¿ (R5/B56), and B¿ (R3/PR72/PR130/PR59). Five isoforms of the human protein are produced by alternative splicing. Isoform 1 (Bbeta1) localizes within the cytoplasm. Isoform 2 (Bbeta2) localizes to both cytosolic and mitochondrial compartments under basal conditions, relocating to the mitochondrial compartment during apoptosis. Its targeting to the outer mitochondrial membrane (OMM) involves an association with import receptors of the TOM complex and is required to promote proapoptotic activity. The N-terminal 26 residues of isoform 2 constitute a cryptic mitochondrial matrix import signal that is necessary and sufficient for targeting the PP2A holoenzyme to the OMM. The last WD repeat of isoform 2 constitutes a mitochondrial stop-transfer domain that prevents PPP2R2B matrix translocation and signal sequence cleavage. Defects in PPP2R2B are the cause of spinocerebellar ataxia type 12 (SCA12).

Protein type: Motility/polarity/chemotaxis; Apoptosis; Mitochondrial; Protein phosphatase, regulatory subunit

Chromosomal Location of Human Ortholog: 5q32

Cellular Component: mitochondrial outer membrane; protein phosphatase type 2A complex; cytoskeleton; mitochondrion

Molecular Function: protein binding; protein phosphatase type 2A regulator activity

Biological Process: apoptosis; regulation of catalytic activity; signal transduction

Disease: Spinocerebellar Ataxia 12