Role of {beta}-glucosidase 2 in aberrant glycosphingolipid metabolism: model of glucocerebrosidase deficiency in zebrafish [Research Articles]

β-glucosidases [GBA1 (glucocerebrosidase) and GBA2] are ubiquitous essential enzymes. Lysosomal GBA1 and cytosol-facing GBA2 degrade glucosylceramide (GlcCer); GBA1 deficiency causes Gaucher disease, a lysosomal storage disorder characterized by lysosomal accumulation of GlcCer, which is partly converted to glucosylsphingosine (GlcSph). GBA1 and GBA2 also may transfer glucose from GlcCer to cholesterol, yielding glucosylated cholesterol (GlcChol). Here, we aimed to clarify the role of zebrafish Gba2 in glycosphingolipid metabolism during Gba1 deficiency in zebrafish (Danio rerio), which are able to survive total Gba1 deficiency. We developed Gba1 (gba1–/–), Gba2 (gba2–/–), and double (gba1–/–:gba2–/–) zebrafish knockouts using CRISPR/Cas9 and explored the effects of both genetic and pharmacological interventions on GlcCer metabolism in individual larvae. Activity-based probes and quantification of relevant glycolipid metabolites confirmed enzyme deficiency. GlcSph increased in gba1–/– larvae (0.09 pmol/fish) but did not increase more in gba1–/–:gba2–/– larvae. GlcCer was comparable in gba1–/– and WT larvae but increased in gba2–/– and gba1–/–:gba2–/– larvae. Independent of Gba1 status, GlcChol was low in all gba2–/– larvae (0.05 vs. 0.18 pmol/fish in WT). Pharmacologic inactivation of zebrafish Gba1 comparably increased GlcSph. I...

Source: The Journal of Lipid Research - October 31, 2019 Category: Lipidology Authors: Lelieveld, L. T., Mirzaian, M., Kuo, C.-L., Artola, M., Ferraz, M. J., Peter, R. E. A., Akiyama, H., Greimel, P., van den Berg, R. J. B. H. N., Overkleeft, H. S., Boot, R. G., Meijer, A. H., Aerts, J. M. F. G. Tags: Research Articles Source Type: research