The influence of gasotransmitters on membrane permeability and activity of tonoplast H+-ATPase under oxidative stress

The investigation of the influence of gasotransmitters - a new class of signaling molecules - on the root tissues of red beet ( Beta vulgaris L.) was conducted. It was found, that hydrogen sulfide (H2S) had some stabilizing effect on cellular membranes, reducing their permeability detected with the aid of conductometric technique. The reliable influence of carbon monoxide (CO) and nitrogen oxide (NO) in our experiments was not observed. A significant increase in efflux of electrolytes from beet tissue under oxidative stress was observed. The addition of gasotransmitters failed to reduce it reliably. Under normal conditions, no appreciable effect of gasotransmitters on tonoplast H+-ATPase transport activity was found. Under oxidative stress, NO and H2S increased the H+-ATPase activity, reduced significantly by the impact of hydrogen peroxide, but did not recover it completely. CO enhanced the negative impact of oxidative stress, and reduced H+-ATPase transport activity. The results obtained suggest a possible conclusion that the gaseous signaling molecules take part in the regulation of transport processes in plant cell through the control of H+-ATPase activity under oxidative stress.