Abstract
Lafora Disease (LD) is an autosomal recessive, neurodegenerative, myoclonus epilepsy that is characterized by the formation of polyglucosan inclusion bodies, called Lafora bodies (LB). Previous studies of LD using gene knockout mouse models have found a direct link between laforin, a tyrosine dual specificity phosphatase, and malin, an E3 ubiquitin ligase, with LB formation, though the underlying biochemical mechanism remains unknown. Yeast models have been successfully used to study other neurodegenerative disease as a human transgene proteotoxicity model and may be useful in understanding the mechanisms of LD. Here, we report the elementary steps in the establishment of a human transgene yeast proteotoxicity model specific for LD. Wildtype human laforin and malin have been introduced into yeast strains using centromeric and non-centromeric plasmids. Additionally, genes containing three disease-causing mutations have been individually incorporated into plasmids (K87A and C226S for laforin and D146N for malin). Foci formation has been observed in the laforin C226S strain under fluorescence microscopy in nitrogen starvation conditions. The observation of aggregates validates the strong potential of this model. The characterization of disease relevant mutants in an established model will aid in the investigations of the underlying molecular mechanisms involving glycogen metabolism and the pathogenesis of LD.