Mitochondrial creatine kinase: a major constituent of pathological inclusions seen in mitochondrial myopathies.
Overaccumulation of abnormally organized mitochondria in so-called "ragged-red" skeletal muscle fibers is a morphological hallmark of mitochondrial myopathies, in particular of mitochondrial encephalomyopathies. Characteristic for the abnormal mitochondria is the occurrence of highly ordered crystalline inclusions. Immuno-electron microscopy revealed that these inclusions react heavily with specific antibodies against mitochondrial creatine kinase (Mi-CK). Image processing of selected crystalline inclusions, sectioned along the crystallographic b, c planes, resulted in an averaged picture displaying an arrangement of regular, square-shaped particles with a central cavity. The overall appearance, dimensions, and symmetry of these building blocks are very reminiscent of single isolated Mi-CK octamers. Taking these findings together, it is concluded that Mi-CK octamers indeed represent the major, if not the only, component of these mitochondrial inclusions.
Stadhouders
A M
AM
Department of Cell Biology and Histology, Faculty of Medical Sciences, University of Nijmegen, The Netherlands.
Jap
P H
PH
Winkler
H P
HP
Eppenberger
H M
HM
Wallimann
T
T
D003402:Creatine Kinase / Q000378:metabolism*; D006801:Humans; D002479:Inclusion Bodies / Q000648:ultrastructure*; D016253:Microscopy, Immunoelectron; D008928:Mitochondria / Q000201:enzymology* / Q000648:ultrastructure; D017240:Mitochondrial Myopathies / Q000201:enzymology* / Q000473:pathology
D003402:Creatine Kinase