Rat H9c2 myoblasts were preconditioned by heat or metabolic stress followed by recovery under normal conditions. Cells were then subjected to severe ATP depletion, and stress-associated proteotoxicity was assessed on 1) the increase in a Triton X-100-insoluble component of total cellular protein and 2) the rate of inactivation and insolubilization of transfected luciferase with cytoplasmic or n...

Hyperthermia adversely affects cell structure and function, but also induces adaptive responses that allow cells to tolerate these stressful conditions. For example, heat-induced expression of the molecular chaperone protein HSP70 can prevent stress-induced cell death by inhibiting signaling pathways that lead to apoptosis. In this study, we used high-resolution two-dimensional gel electrophore...

Elicitation or peroxide stimulation of grape (Vitis vinifera L. cv Touriga) vine callus cultures results in the rapid and selective in situ insolubilization of an abundant and ionically bound cell wall protein-denominated GvP1. Surface-enhanced laser desorption/ionization/time of flight-mass spectrometry analysis, the amino acid composition, and the N-terminal sequence of purified GvP1 identifi...

Activation of the stress response attenuates proinflammatory responses by suppressing cytokine-stimulated activation of the NF-kappaB signaling pathway. In this study, we show that the activation of the cellular stress response, either by heat shock treatment or after exposure to sodium arsenite, leads to a transient inhibition of IkappaBalpha phosphorylation. Inhibition of IkappaBalpha phospho...

A novel amino acid, di-isodityrosine, has been isolated from hydrolysates of cell walls of tomato cell culture. Analysis by UV spectrometry, partial derivatization with 2,4-dinitrofluorobenzene and mass and NMR spectrometry show that the compound is composed to two molecules of isodityrosine, joined by a biphenyl linkage. The possible reactions involved in the formation of this molecule in vivo...