phosphorus-radioisotopes and Gangliosidoses

Cultured fibroblasts from different variants of GM1-gangliosidosis synthesize normal amounts of 88-kDa beta-galactosidase precursor. Yet the amount of the mature 64-kDa form is reduced to 5-15% of normal values. In this communication it is shown that the mutation in the infantile and adult form of GM1-gangliosidosis interferes with the phosphorylation of precursor beta-galactosidase. As a result the precursor is secreted instead of being compartmentalized into the lysosomes and further processed. The impaired phosphorylation might be due to conformational changes of the precursor molecule.

Topics: beta-Galactosidase; Cells, Cultured; Enzyme Precursors; Fibroblasts; G(M1) Ganglioside; Galactosidases; Gangliosidoses; Humans; Molecular Weight; Phosphates; Phosphorus Radioisotopes; Phosphorylation; Protein Processing, Post-Translational; Skin