Epilepsy, Progressive Myoclonus Type 2a (EPM2A) Antibody – Mouse Monoclonal

This gene encodes a dual-specificity phosphatase that associates with polyribosomes. The encoded protein may be involved in the regulation of glycogen metabolism. Mutations in this gene have been associated with myoclonic epilepsy of Lafora. Alternative splicing results in multiple transcript variants. [provided by RefSeq]

laforin: Dual specificity protein phosphatase. May be involved in the control of glycogen metabolism, particularly in monitoring for and preventing the formation of poorly branched glycogen molecules (polyglucosans). Acts as a scaffold protein to facilitate PPP1R3C/PTG ubiquitination by NHLRC1/malin. Forms a complex with NHLRC1/malin and HSP70 and this complex suppresses the cellular toxicity of misfolded proteins by promoting their degradation through the ubiquitin-proteasome system (UPS). Isoform 2, an inactive phosphatase, could function as a dominant-negative regulator for the phosphatase activity of isoform 1. Defects in EPM2A are a cause of progressive myoclonic epilepsy type 2 (EPM2); also known as Lafora disease. EPM2 is an autosomal recessive and severe form of adolescent-onset progressive epilepsy. Typically, as seizures increase in frequency, cognitive function declines towards dementia, and affected individuals die usually within 10 years after onset. EPM2 occurs worldwide, but it is particularly common in the mediterranean countries of southern Europe and northern Africa, in southern India and in the Middle East. At the cellular level, it is characterized by accumulation of starch-like polyglucosans called Lafora bodies (LBs) that are most abundant in organs with the highest glucose metabolism: brain, heart, liver and skeletal muscle. Among other conditions involving polyglucosans, EPM2 is unique in that the inclusions are in neuronal dendrites but not axons and the forming polyglucosan fibrils are associated with the endoplasmic reticulum. Belongs to the protein-tyrosine phosphatase family. 9 isoforms of the human protein are produced by alternative splicing.

Protein type: EC 3.1.3.16; Protein phosphatase, dual-specificity; EC 3.1.3.48; Motility/polarity/chemotaxis

Chromosomal Location of Human Ortholog: 6q24

Cellular Component: polysome; endoplasmic reticulum; cytoplasm; plasma membrane; cytosol; nucleus

Molecular Function: protein binding; phosphoinositide 5-phosphatase activity; protein tyrosine/serine/threonine phosphatase activity; carbohydrate phosphatase activity; protein tyrosine phosphatase activity; protein serine/threonine phosphatase activity

Biological Process: glycogen metabolic process; nervous system development; glycogen biosynthetic process; habituation; inositol phosphate dephosphorylation; carbohydrate metabolic process; glucose metabolic process; autophagy; pathogenesis; protein amino acid dephosphorylation

Disease: Myoclonic Epilepsy Of Lafora