laforin Plays an important role in preventing glycogen hyperphosphorylation and the formation of insoluble aggregates, via its activity as glycogen phosphatase, and by promoting the ubiquitination of proteins involved in glycogen metabolism via its interaction with the E3 ubiquitin ligase NHLRC1/malin. Shows strong phosphatase activity towards complex carbohydrates in vitro, avoiding glycogen hyperphosphorylation which is associated with reduced branching and formation of insoluble aggregates. Dephosphorylates phosphotyrosine and synthetic substrates, such as para-nitrophenylphosphate (pNPP), and has low activity with phosphoserine and phosphothreonine substrates (in vitro). Has been shown to dephosphorylate MAPT. Forms a complex with NHLRC1/malin and HSP70, which suppresses the cellular toxicity of misfolded proteins by promoting their degradation through the ubiquitin-proteasome system (UPS). Acts as a scaffold protein to facilitate PPP1R3C/PTG ubiquitination by NHLRC1/malin. Also promotes proteasome-independent protein degradation through the macroautophagy pathway. Isoform 2: does not bind to glycogen. Lacks phosphatase activity and might function as a dominant-negative regulator for the phosphatase activity of isoform 1 and isoform 7. Isoform 7: has phosphatase activity (in vitro). Belongs to the protein-tyrosine phosphatase family. Expressed in heart, skeletal muscle, kidney, pancreas and brain. Isoform 4 is also expressed in the placenta. 8 alternative splicing and alternative initiation human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: EC; EC; Motility/polarity/chemotaxis; Protein phosphatase, dual-specificity
Chromosomal Location of Human Ortholog: 10|10 A1
Cellular Component:  cytoplasm; cytoplasmic side of endoplasmic reticulum membrane; cytoplasmic side of rough endoplasmic reticulum membrane; cytosol; dendrite; endoplasmic reticulum; membrane; nucleoplasm; nucleus; perikaryon; plasma membrane
Molecular Function:  carbohydrate binding; carbohydrate phosphatase activity; hydrolase activity; phosphatase activity; phosphoprotein phosphatase activity; polysaccharide binding; protein binding; protein dimerization activity; protein homodimerization activity; protein serine/threonine phosphatase activity; protein tyrosine phosphatase activity; protein tyrosine/serine/threonine phosphatase activity; starch binding
Biological Process:  autophagosome assembly; autophagy; calcium ion transport; carbohydrate metabolic process; cellular macromolecule metabolic process; dephosphorylation; glial cell proliferation; glycogen biosynthetic process; glycogen metabolic process; habituation; L-glutamate transmembrane transport; mitochondrion organization; negative regulation of cell cycle; negative regulation of dephosphorylation; negative regulation of gene expression; negative regulation of peptidyl-serine phosphorylation; negative regulation of phosphatase activity; negative regulation of TOR signaling; nervous system development; peptidyl-tyrosine dephosphorylation; phosphorylated carbohydrate dephosphorylation; positive regulation of macroautophagy; proteasome-mediated ubiquitin-dependent protein catabolic process; protein dephosphorylation; protein homooligomerization; regulation of cell growth; regulation of gene expression; regulation of glycogen (starch) synthase activity; regulation of phosphorylation; regulation of proteasomal protein catabolic process; regulation of protein import into nucleus; regulation of protein kinase activity; regulation of protein localization to plasma membrane; regulation of protein phosphorylation; regulation of protein ubiquitination; regulation of ubiquitin protein ligase activity; Wnt signaling pathway
Reference #:  Q9WUA5 (UniProtKB)
Alt. Names/Synonyms: epilepsy, progressive myoclonic epilepsy, type 2 gene alpha; Epm2a; Glucan phosphatase; Lafora PTPase; Laforin; LAFPTPase; Tg(TcraK,TcrbK)TG-BFlv; TG-B
Gene Symbols: Epm2a
Molecular weight: 36,958 Da
Basal Isoelectric point: 5.87  Predict pI for various phosphorylation states
Select Structure to View Below


Protein Structure Not Found.

Cross-references to other databases:  AlphaFold  |  STRING  |  BioGPS  |  Pfam  |  ENZYME  |  Phospho.ELM  |  NetworKIN  |  UniProtKB  |  Entrez-Gene  |  Ensembl Gene