Question

Fibroblast cells from a patient contain “inclusion bodies”, which are lysosomes filled with undigested material. What are possible cellular basis that causes accumulations of undigested material in lysosomes? Please use less than four sentences to answer this question. (4 pts)

Answer 1

Inclusion cell disease (I-cell disease) is a type of lysosomal storage disease, which results in the presence of inclusion bodies (Accumulation of undigested macromolecules and other insolubles) in fibroblasts throughout the body. It is an autosomal recessive disease caused by the deficiency of the enzyme N-acetyl Glucosamine 1-phosphotransferase, which phosphorylates mannose residues of N-linked Glycoproteins present in Golgi apparatus of cells. The phosphorylation of mannose residues targets proteins that are catabolic enzymes to lysosomes; without the signal, proteins will not be translocated to lysosomes and hence it cannot carry out the normal digestion of substances including fat, proteins and carbohydrates.