Laforin is a cell membrane and endoplasmic reticulum-associated protein tyrosine phosphatase

• Published in: Annals of neurology Vol. 49; no. 2; pp. 271 - 275
• Main Authors: Minassian, Berge A., Andrade, Danielle M., Ianzano, Leonarda, Young, Edwin J., Chan, Elayne, Ackerley, Cameron A., Scherer, Stephen W.
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 01.02.2001; Willey-Liss
• Subjects: Amyotrophic Lateral Sclerosis - genetics; Biological and medical sciences; Cell Membrane - metabolism; Endoplasmic Reticulum - metabolism; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Humans; Medical sciences; Myoclonic Epilepsies, Progressive - genetics; Nervous system (semeiology, syndromes); Neurology; Protein Tyrosine Phosphatases - genetics; Protein Tyrosine Phosphatases - metabolism; Protein Tyrosine Phosphatases, Non-Receptor; Human; Nervous system diseases; Myoclonus; Pathophysiology; Enzyme; Epilepsy; Fluorescence; Phosphoric monoester hydrolases; Esterases; Gene expression; Electron microscopy; Cerebral disorder; Involuntary movement; Pathology; Optical microscopy; Central nervous system disease; Plasma membrane; Hydrolases; Neurological disorder; Endoplasmic reticulum
• ISSN: 0364-5134; 1531-8249
• DOI: 10.1002/1531-8249(20010201)49:2<271::AID-ANA52>3.0.CO;2-D

Lafora disease (LD) is the only progressive myoclonus epilepsy with polyglucosan bodies. Among conditions with polyglucosan bodies, LD is unique for the subcellular location of its polyglucosans in neuronal perikarya and dendrites and not in axons. Here we report that the protein encoded by the EPM2A gene, which is mutated in LD, localizes at the plasma membrane and the endoplasmic reticulum and that it is a functional protein tyrosine phosphatase. The significance of these findings in the epilepsy of LD and in the origin and characteristic subcellular location of Lafora bodies is discussed. Ann Neurol 2001;49:271–275