In higher plants, peroxisomes have been believed to play a pivotal role in three metabolic pathways, which are lipid breakdown, photorespiration and H2O2-detoxificaton. Recently, significant progress in the study of plant peroxisomes was established by forward-/reverse-genetics and post-genomic approaches using Arabidopsis thaliana, the first higher plant to have its entire genome sequenced. Th...

Peroxisomes are unique among the organelles of the endomembrane system. Unlike other organelles that derive most if not all of their proteins from the ER (endoplasmic reticulum), peroxisomes contain dedicated machineries for import of matrix proteins and insertion of membrane proteins. However, peroxisomes are also able to import a subset of their membrane proteins from the ER. One aspect of pe...

Bacterial genes responsible for poly(3-hydroxybutyrate) (PHB) biosynthesis were targeted to plant peroxisomes by adding a carboxy-terminal targeting sequence. The enzymes evidently were transported into peroxisomes, retained their catalytic activity, and reacted with peroxisomally available precursors because PHB synthesis in transgenic plant cells was localized to peroxisomes. Up to 2 mg/g fre...

In this study, by using highly purified rat liver peroxisomes, we provide evidence from analytical cell fractionation, Western blot, and immunocytochemical analysis that Cu-Zn superoxide dismutase is present in animal peroxisomes. Treatment with ciprofibrate, a peroxisome proliferator, increased the peroxisomal superoxide dismutase activity by 3-fold with no effect on mitochondrial activity but...

Using morphological and biochemical (Western blot and cell fractionation) methods, we investigated whether peroxisomes are present in human extravillous trophoblast cells. Immortalized extravillous trophoblast cells (TCL-1) were incubated in the presence or absence of 0.5 mM clofibric acid for 3 d. In immunofluorescence staining of trophoblast cells with antibodies anti-catalase and anti-acyl-C...

Peroxisomes are ubiquitous organelles that proliferate under different physiological conditions and can form de novo in cells that lack them. The endoplasmic reticulum (ER) has been shown to be the source of peroxisomes in yeast and plant cells. It remains unclear, however, whether the ER has a similar role in mammalian cells and whether peroxisome division or outgrowth from the ER maintains pe...

To understand the basis of excretion of excessive amounts of epoxydicarboxylic fatty acids (EDFA) in urine of patients with disorders of peroxisomal biogenesis (Pitt, J. J., and A. Poulos. 1993. Clin. Chim. Acta. 223: 23-29), the activity of epoxide hydrolase (EH) was measured in cultured skin fibroblasts from control subjects and patients with peroxisomal disorders. EH activity was approximate...

in this presentation, we review briefly on biogenesis of peroxisomes with regard to the recent findings on biogenesis. peroxisomes perform a range of various functions as oxidation of very long chain fatty acids, generation and removal of hydrogen peroxide, while peroxisomes have also been implicated in β-oxidation of aromatic and cyclic compounds, synthesis of plasmalogens, isoprenoids, lysine...

Eukaryotic cells compartmentalize biochemical reactions into membrane-enclosed organelles that must be faithfully propagated from one cell generation to the next. Transport and retention processes balance the partitioning of organelles between mother and daughter cells. Here we report the identification of an ER-peroxisome tether that links peroxisomes to the ER and ensures peroxisome populatio...

Peroxisomes are ubiquitous eukaryotic organelles, which perform a plethora of functions including hydrogen peroxide metabolism and β-oxidation of fatty acids. Reactive oxygen species produced by peroxisomes are a major contributing factor to cellular oxidative stress, which is supposed to significantly accelerate aging and cell death according to the free radical theory of aging. However, relat...