Categories: Lysosomal storage disease

Possible human homologues (MIM numbers): 252500 (trait) , 607840 (gene) , 252600 (trait)

Cross-species summary: Mucolipidosis II (also known as I-cell disease) is a lysosomal storage disease in which there is a buildup (storage) of a range of macromolecules (which remain visible in the form of lysosomal inclusions: so-called I-cells), due to the lack of a range of lysosomal enzymes whose task is to break down the macromolecules into their constituents. Unlike a 'typical' lysosomal storage disease which is due to the lack of a particular lysosomal enzyme, I-cell disease results from the lack of the Golgi enzyme UDP-N-acetylglucosamine-1-phosphotransferase (GlcNAc-phosphotransferase) (EC 2.7.8.17), whose task is to attach phosphate groups to mannose residues of soluble lysosomal enzymes. The consequent lack of a mannose-6-phosphate (M-6-P) recognition site means that the enzymes cannot be transported via M-6-P receptors to the lysosomes, ending up instead in extracellular space. Thus, lysosomes are deficient in a range of lysosomal enzymes, while serum and extracellular fluids show elevated activity of these enzymes.

Species in which this phene is found:
domestic cat (Felis catus)