[Alteration in the Expression of Genes Encoding Primary Metabolism Enzymes and Plastid Transporters during the Culture Growth of Chlamydomonas reinhardtii].

In a mixotrophic Chlamydomonas reinhardtii culture, the expression levels of genes encoding primary metabolic enzymes and chloroplast plastid transporters were analyzed. For the majority of the genes studied, their expression levels decreased as they approached the final stages of culture growth. During the period of exponential growth, the expression profiles changed more intensively than during the stationary phase. In the middle of exponential growth, significant changes of mRNA profiles reflected reorganization of metabolism, with an emphasis on the induction of lipid synthesis, accompanied by alterations in carbon fluxes through biochemical pathways and a shift in the energy balance between the plastid and cytosol.

[Alteration of transport activity of proton pumps in coleoptile cells during early development stages of maize seedlings].

Comparative analysis of the transport activity of proton pumps (plasmalemma H+-ATPase, vacuolar H+-ATPase, and vacuolar H+-pyrophosphatase) in the membrane preparations obtained from coleoptile cells ofetiolated maize seedlings (Zea mays L.) was carried out. The highest level ofvacuolar pyrophosphatase activity was observed during the early development of coleoptile cells under growth intensification through the elongation. The role of ATPase pumps of tonoplast and plasmalemma in the transport of hydrogen ions increases during further development. The plasmalemma activity in this process is higher. When the growth stops, the activity of proton pumps becomes significantly lower. Nevertheless, their substrate specificity and sensitivity to proton pump inhibitors do not change, which can be an evidence of physiological significance of pumps in the maintenance of cell homeostasis.