We previously reported that the lower activity of mevalonate pyrophosphate decarboxylase (MPD) was caused by the reduced amount of this enzyme in stroke-prone spontaneously hypertensive rat (SHRSP) by immunoblot analysis using 20,000 x g supernatant containing cytosol and microsomes. A recent study showed that at least three different subcellular compartments, including peroxisomes, are involve...

Cellular proteins and organelles such as peroxisomes are under continuous quality control. Upon synthesis in the cytosol, peroxisomal proteins are kept in an import-competent state by chaperones or specific proteins with an analogous function to prevent degradation by the ubiquitin-proteasome system. During protein translocation into the organelle, the peroxisomal targeting signal receptors (Pe...

Peroxisomes are metabolically diverse organelles with essential roles in plant development. The major protein constituents of plant peroxisomes are well characterized, whereas only a few low-abundance and regulatory proteins have been reported to date. We performed an in-depth proteome analysis of Arabidopsis (Arabidopsis thaliana) leaf peroxisomes using one-dimensional gel electrophoresis foll...

In the last century peroxisomes were thought to have an endosymbiotic origin. Along with mitochondria and chloroplasts, peroxisomes primarily regulate their numbers through the growth and division of pre-existing organelles, and they house specific machinery for protein import. These features were considered unique to endosymbiotic organelles, prompting the idea that peroxisomes were key cellul...

Peroxisomes are considered to form either by growth and division of existing peroxisomes or de novo from the endoplasmic reticulum. A recent study now demonstrates that mitochondria-derived vesicles are also required for de novo peroxisome biogenesis.

Seeing peroxisomes t about the same time that Christian de Duve and his colleagues were describing the biochemistry of lysosomes (see “Catching sight of lysosomes” JCB 168: 174), they biochemically identified (Baudhuin et al., 1965) and purified (Leighton et al., 1968) another enzyme-containing organelle. Initially the organelle was known as the microbody, and de Duve declined to give it a more...

BACKGROUND Peroxisomes are small cellular organelles that were almost ignored for years because they were believed to play only a minor role in cellular functions. However, it is now known that peroxisomes play an important role in regulating cellular proliferation and differentiation as well as in the modulation of inflammatory mediators. In addition, peroxisomes have broad effects on the meta...

On the basis of differential and density gradient centrifugation studies, the site of the uric acid degrading enzymes, urate oxidase and allantoinase, in amphibia was previously assigned to the hepatic peroxisomes. Using specific antibodies against frog urate oxidase and allantoinase, we have undertaken an immunocytochemical study of the localization of these two proteins in frog liver and kidn...

The repeated administration of the hypolipidemic agent Su-13 437 (nafenopin) to neonatal rats roughly doubled the number of peroxisomes in the liver tissue and caused a sixfold volumetric expansion of the peroxisomal compartment. During the proliferative response, the size-distribution of the peroxisomes was reversibly altered, enlarged particles appearing in numbers varying according to the do...

Peroxisomes, single-membrane-bounded organelles with essentially oxidative metabolism, are key in plant responses to abiotic and biotic stresses. Recently, the presence of nitric oxide (NO) described in peroxisomes opened the possibility of new cellular functions, as NO regulates diverse biological processes by directly modifying proteins. However, this mechanism has not yet been analysed in pe...