Tag Archives: lipid peroxidation
Functions of tocopherols in the cells of plants and other photosynthetic organisms
V. M. Mokrosnop
M. G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine, Kyiv;
e-mail: VictoryM6@yandex.ua
Tocopherol synthesis has only been observed in photosynthetic organisms (plants, algae and some cyanobacteria). Tocopherol is synthesized in the inner membrane of chloroplasts and distributed between chloroplast membranes, thylakoids and plastoglobules. Physiological significance of tocopherols for human and animal is well-studied, but relatively little is known about their function in plant organisms. Among the best characterized functions of tocopherols in cells is their ability to scavenge and quench reactive oxygen species and fat-soluble by-products of oxidative stress. There are the data on the participation of different mechanisms of α-tocopherol action in protecting photosystem II (PS II) from photoinhibition both by deactivation of singlet oxygen produced by PS II and by reduction of proton permeability of thylakoid membranes, leading to acidification of lumen under high light conditions and activation of violaxanthin de-epoxidase. Additional biological activity of tocopherols, independent of its antioxidant functions have been demonstrated. Basic mechanisms for these effects are connected with the modulation of signal transduction pathways by specific tocopherols and, in some instances, by transcriptional activation of gene expression.
Laureates of the Palladin Prize of the National Academy of Sciences of Ukraine (1997–1998)
R. P. Vynogradova, V. M. Danilova
Palladin Insitute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: valdan@biochem.kiev.ua
V. A. Baraboi received the O.V. Palladin prize in 1997 for the series of works “The role of lipid peroxidation in the mechanism of ionizing radiation damage and stress”. O. Iu. Petrenko, O. M. Sukochov, L. P. Kravchenko were awarded the O.V. Palladin prize in 1998 for the series of works “The function of intracellular structures in isolated hepatocytes depending on the metabolic status and the effects of low temperatures”.