Mitochondrial dysfunction (depolarization and structural collapse), cytosolic ATP depletion, and neuritic beading are early hallmarks of neuronal toxicity induced in a variety of pathological conditions. We show that, following global exposure to glutamate, mitochondrial changes are spatially and temporally coincident with dendritic bead formation. During oxygen-glucose deprivation, mitochondri...

The proapoptotic mammalian protein Bax associates with mitochondrial membranes and confers a lethal phenotype when expressed in yeast. By generating Bax-resistant mutant yeast and using classical complementation cloning methods, subunits of the mitochondrial F0F1-ATPase proton pump were determined to be critical for Bax-mediated killing in S. cerevisiae. A pharmacological inhibitor of the proto...

The influence of ConA on the energy metabolism of quiescent rat thymocytes was investigated by measuring the effects of inhibitors of protein synthesis, proteolysis, RNA/DNA synthesis, Na+K(+)-ATPase, Ca(2+)-ATPase and mitochondrial ATP synthesis on respiration. Only about 50% of the coupled oxygen consumption of quiescent thymocytes could be assigned to specific processes using two different m...

Background and Aim: New anticancer drugs are being developed to avoid the toxicity chemoresistance of currently available drugs. The Food Drug Administration-approved anti-malarial drug atovaquone is known act as a selective oxidative phosphorylation inhibitor in mitochondria by competing with CO Q10 (mitochondrial complex II III). This study aimed investigate effect examining Na+/K+-ATPase (NK...

Ligand-binding studies with labelled triethyltin on yeast mitochondrial membranes showed the presence of high-affinity sites (KD = 0.6juM; 1.2± 0.3nmol/mg of protein) and low-affinity sites (KD>45UM; 70± 20nmol/mg of protein). The dissociation constant of the high-affinity site is in good agreement with the concentration of triethyltin required for inhibition of mitochondrial ATPase (adenosine ...

To investigate the effects of training in normoxia vs. training in normobaric hypoxia (fraction of inspired O2 = 20.9 vs. 13.5%, respectively) on the regulation of Na+-K+-ATPase pump concentration in skeletal muscle (vastus lateralis), 9 untrained men, ranging in age from 19 to 25 yr, underwent 8 wk of cycle training. The training consisted of both prolonged and intermittent single leg exercise...

The activation of mitochondrial adcnosine triphosphatase (EC 3.6.1.4) by Mg++ has been studied extensively, particularly in connection with the mechanism of oxidative phosphorylation (1). However, virtually nothing is known about the interaction of ATPase with 5’-triphosphate ribonucleotides and the role of Mg++ in activating the enzyme. One of the key problems in this field appears to be wheth...

Translocation of proteins across the mitochondrial inner membrane is an essential process requiring an import motor having mitochondrial Hsp70 (mtHsp70) at its core. The J protein partner of mtHsp70, Pam18, is an integral part of this motor, serving to stimulate the ATPase activity of mtHsp70. Pam16, an essential protein having an inactive J domain that is unable to stimulate mtHsp70's ATPase a...

A longitudinal cross-over feeding design was used to investigate the relationship of dietary lipid composition to the membrane lipid environment and activity of mitochondrial ATPase in vivo. Rats were fed a polyunsaturated fatty-acid-rich oil (soya-bean oil) for 12 days, crossed-over to a monounsaturated fatty-acid-rich oil (rapeseed oil) for the next 11 days, then returned to soya-bean oil for...