DEVELOPMENT OF NOVEL FLUORESCENCE-QUENCHED PROBES FOR MONITORING LYSOSOMAL GLYCOSIDASE ACTIVITY IN LIVE CELLS

摘要

α-Galactosidase A (GalA) and ss-Glucocerebrosidase (GCase) are two lysosomal glycoside hydrolases that process globotriaosylceramide and glucosylceramide. Deficiencies of these glycosidases, which are commonly linked to mutations of their encoding genes GLA and GBA1, lead to the accumulation of their respective substrates and the development of the lysosomal storage disorders Fabry disease (FD) and Gaucher disease (GD) [1]. These mutations ultimately lead to the expression of unstable forms of the enzymes, which do not reach the lysosome [2]. As a result, the levels of active enzyme within the lysosome are reduced. Current therapeutic strategies to increase enzyme activity in the lysosome involve enzyme replacement therapy and chaperone therapy [3]. A challenge associated with optimizing and advancing these therapies is to quantitatively measure enzyme activity within the lysosome of live cells.