Cystine storage in cultured myotubes from patients with nephropathic cystinosis.
Sorted muscle cells, cultured from a patient with nephropathic cystinosis, stored 100 times normal amounts of cystine. Subcellular fractionation and density-gradient centrifugation confirmed that the cystine was located in a lysosomal compartment. 2. Myoblasts from cystinotic patients in culture underwent fusion to myotubes in a normal fashion. 3. The free thiol cysteamine effectively depleted cystinotic-muscle cells of cystine. 4. Cultured myoblast and myotubes offered a unique system for investigating the effects of lysosomal storage on differentiated cell functions.
Harper
G S
GS
Human Genetics Branch, NICHD, Bethesda, MD 20892.
Bernardini
I
I
Hurko
O
O
Zuurveld
J
J
Gahl
W A
WA
D002478:Cells, Cultured; D002499:Centrifugation, Density Gradient; D003543:Cysteamine / Q000378:metabolism; D003553:Cystine / Q000378:metabolism*; D003554:Cystinosis / Q000378:metabolism*; D006801:Humans; D009132:Muscles / Q000166:cytology / Q000378:metabolism*
D003553:Cystine; D003543:Cysteamine