Diabetes mellitus is defined as a state of persistently high levels of blood glucose and insulin deficiency, and resistance to it is considered as the cause(s). However, the metabolic abnormalities of diabetes are not limited to glucose, but encompass the entire metabolism. Insulin controls not only glucose, but fat and protein metabolism as well. Furthermore, body structures of patients with t...

The mitochondrion has cut back its genome substantially since taking up residence in cells as a symbiont 1.5 billion years ago, but it retains its personal transcription, translation and protein-assembling systems, including its tRNA genes. Even so, the mitochondrion is not fully self-sufficient — to varying extents yeast, plants and protozoan cells can borrow nuclear-encoded tRNA molecules to ...

Ferrochelatase (FECH) is an essential enzyme for the final step of heme biosynthesis. In green plants, its activity has been reported in both plastids and mitochondria. However, the precise subcellular localization of FECH remains uncertain. In this study, we analyzed the localization of FECH in the unicellular red alga, Cyanidioschyzon merolae. Immunoblot and enzyme activity analyses of subcel...

The fine structure of mitochondria and mitochondrial nucleoids in exponentially growing Physarum polycephulum was studied at various periods throughout the mitochondrial division cycle by light and electron microscopy. The mitochondrial nucleoid elongates longitudinally while the mitochondrion increases in size. When the nucleoid reaches a length of approximately 1.5 ~m the mitochondrial membra...

Subcellular localization of von Hippel-Lindau (VHL) tumor suppressor may clarify its role in tumorigenesis. In rat kidney, we observed a granular cytoplasmic immunostaining of VHL, as seen in human tissues. The green fluorescent protein (GFP)-tagged VHL also appeared as cytoplasmic granules in vitro and was colocalized with a mitochondrion-selective dye. Immunogold electron microscopy localized...

The free radical theory of aging is almost 60 years old. As mitochondria are the principle source of intracellular reactive oxygen species (ROS), this hypothesis suggested a central role for the mitochondrion in normal mammalian aging. In recent years, however, much work has questioned the importance of mitochondrial ROS in driving aging. Conversely new evidence points to other facets of mitoch...

There is increasing evidence that accumulation of redox-active iron in mitochondria leads to oxidative damage and contributes to various neurodegenerative diseases, such as Friedreich's ataxia and Parkinsons disease. In this work, we examined the existence of regulatory mechanisms for mitochondrial iron uptake and storage. To that end, we used rhodamine B-[(1,10-phenanthrolin-5-yl)amino carbony...