Molecular background of progressive myoclonus epilepsy.
Research on human inherited diseases provides a powerful tool to identify an intrinsically important subset of genes vital to healthy functioning of the organism. Progressive myoclonus epilepsies (PMEs) are a group of rare inherited disorders characterized by the association of epilepsy, myoclonus and progressive neurological deterioration. Significant progress has been made in elucidating the molecular background of PMEs. Here, progress towards understanding the molecular pathogenesis of PMEs is reviewed using the most common single cause of PME, Unverricht-Lundborg disease, as an example. Mutations in the gene encoding cystatin B (CSTB), a cysteine protease inhibitor, are responsible for the primary defect in Unverricht-Lundborg disease. CSTB-deficient mice, produced by targeted disruption of the mouse Cstb gene, display a phenotype similar to the human disease, with progressive ataxia and myoclonic seizures. The mice show neuronal atrophy, apoptosis and gliosis as well as increased expression of apoptosis and glial activation genes. Although significant advances towards understanding the molecular basis of Unverricht-Lundborg disease have been achieved, the physiological function of CSTB and the molecular pathogenesis of the disease remain unknown.
Lehesjoki
Anna-Elina
AE
Folkhälsan Institute of Genetics and Department of Medical Genetics, University of Helsinki, PO Box 63 (Haartmaninkatu 8), FIN-00014 Helsinki, Finland. anna-elina.lehesjoki@helsinki.fi
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000235:genetics; D001483:Base Sequence; D002891:Chromosomes, Human, Pair 21; D015891:Cystatins / Q000172:deficiency / Q000235:genetics; D015853:Cysteine Proteinase Inhibitors / Q000172:deficiency / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D020191:Myoclonic Epilepsies, Progressive / Q000235:genetics*; D017354:Point Mutation; D017386:Sequence Homology, Amino Acid; D020194:Unverricht-Lundborg Syndrome / Q000235:genetics
D015891:Cystatins; D015853:Cysteine Proteinase Inhibitors