Tag Archives: Methyure
Function of transport H(+)-ATPases in plant cell plasma and vacuolar membranes of maize under salt stress conditions and effect of adaptogenic preparations
Zh. I. Ribchenko, Т. A. Palladina
Kholodny Institute of Botany, National Academy of Sciences of Ukraine, Kyiv;
e-mail: zhanna_bio@ukr.net, tatiana_palladina@ ukr.net
Participations of electrogenic H+-pumps of plasma and vacuolar membranes represented by E1-E2 and V-type H+-ATPases in plant cell adaptation to salt stress conditions has been studied by determination of their transport activities. Experiments were carried out on corn seedlings exposed during 1 or 10 days at 0.1 M NaCl. Preparations Methyure and Ivine were used by seed soaking at 10-7 M. Plasma and vacuolar membrane fractions were isolated from corn seedling roots. In variants without NaCl a hydrolytical activity of plasma membrane H+-ATPase was increased with seedling age and its transport one was changed insignificantly, wherease the response of the weaker vacuolar H+-ATPase was opposite. NaCl exposition decreased hydrolytical activities of both H+-ATPases and increased their transport ones. These results demonstrated amplification of H+-pumps function especially represented by vacuolar H+-ATPase. Both preparations, Methyure mainly, caused a further increase of transport activity which was more expressed in NaCl variants. Obtained results showed the important role of these H+-pumps in plant adaptation under salt stress conditions realized by energetical maintenance of the secondary active Na+/H+-antiporters which remove Na+ from cytoplasm.
Effect of preparations Methyure and Ivine on Са(2+)-ATPases activity in plasma and vacuolar membrane of corn seedling roots under salt stress conditions
M. V. Rudnytska, T. A. Palladina
Kholodny Institute of Botany, National Academy of Sciences of Ukraine, Kyiv
e-mail: tatiana_palladina@ukr.net
Ca2+-ATPases regulate the functioning of Ca2+-dependent signaling pathway SOS which provides removal of Na+ from the cytoplasm of cells via Na+/H+-antiporters in saline conditions. The influence of synthetic preparations Methyure and Ivine on the Ca2+-ATPase activity was investigated. It was shown that exposition of corn seedlings in the presence of 0.1 M NaCl rather enhanced hydrolytic than transport activity of Ca2+-ATPases in plasma and vacuolar membrane of root cells. It was found that seed treatment with such preparations, especially Methyure, caused intensification of the both activities of Ca2+-ATPases, mainly in vacuolar membrane. The results indicate than salt protective activity of preparations, especially Methyure, is associated with increased Ca2+-ATPase activity, which regulates the functioning of Na+/H+-antiporters.
Ascorbate-glutathione cycle enzymes activity in zea mays leaves under salinity and treatment by adaptogenic compounds
O. O. Konturska, T. O. Palladina
M. G. Kholodny Institute of Botany, National Academy of Science of Ukraine, Kyiv;
e-mail: konturska@ukr.net
The effect of different salinity levels and synthetic compounds treatments on ascorbate-glutathione cycle enzymes activity in maize leaves has been investigated. One-day seedlings exposition with 0.05 М NaCl increased ascorbate peroxidase activity, whereas 10-day exposition did not affect it. However the exposition with 0.1 M NaCl, which is extreme for maize, decreased ascorbate peroxidase activity in leaves during 10 days. On the other hand glutathione reductase activity in leaves increased under both salt concentrations. Seeds treatments with Methyure and Ivine increased ascorbate peroxidase activity in the leaves of seedlings under 0.1 М NaCl, but did not affect glutathione reductase activity as compared to the salt control. The results obtained have shown differences of ascorbate-glutathione cycle enzymes responses to salt exposition of seedlings and the effects of adaptogenic compounds on the ascorbate-glutathione cycle via ascorbate peroxidase activation.
Gene expression of H(+)-pumps in plasma and vacuolar membranes of corn root cells under the effect of sodium ions and bioactive preparations
N. O. Kovalenko, T. A. Palladina
Kholodny Institute of Botany, National Academy of Sciences of Ukraine, Kyiv;
e-mail: tatiana_palladina@ukr.net
Four isoforms of H+-ATPase of plasma membrane: MHA1, MHA2, MHA3, MHA4 are expressed in the corn seedling roots with prevalence of genes MHA3 і MHA4. The exposure of seedlings in the presence of 0.1 M NaCl activated the expression of MHA4 gene isoform, that demonstrates its important role in the processes of adaptation to salinization conditions. In vacuolar membrane, where potential is created by two Н+-pumps, sodium ions activated gene expression of only Н+-АТРase of V-type, taking no effect on the expression of Н+-pyrophosphatase. The seeds pretreatment by synthetic preparations Methyure and Ivine did not affect gene expression of Н+-pumps. Thus we can suppose that the ability of the above preparations to activate functioning of Н+-pumps in the presence of sodium ions is realized at the post-tranlation level.
The action of adaptogenic preparations on vacuolar proton рumps activity in corn root cells under salt stress conditions
Zh. I. Ribchenko, Т. A. Palladina
Kholodny Institute of Botany, National Academy of Sciences of Ukraine, Kyiv;
e-mail: zhanna_bio@ukr.net; tatiana_palladina@ ukr.net
The function of two electrogenic H+-pumps in plant vacuolar membrane (tonoplast) and their response to the salt stress conditions and adaptogenic preparations have been studied. Experiments were carried out on tonoplast fraction isolated from the roots of corn seedlings grown in water culture which were exposed at 7-day age in the presence of 0.1 M NaCl during 1 or 10 days. The role of every H+-pump in potential generation was elucidated by assaying transport and hydrolytic activity of enzymes – V-type H+-ATPase and H+-pyrophosphatase represented their mechanisms. It was found in the control variant that transport activity H+-PPase exceeded considerably H+-ATPase one in the tonoplast from 7-day seedlings. However this situation was changed in 18-day seedlings by H+-ATPase transport activity increasing with age whereas its hydrolytic one was decreased. Both NaCl expositions caused the progressive decrease of transport and hydrolytic activity of H+-PPase whereas Н+-ATPase responded to this factor by increasing transport activity, while its hydrolytic one fell. Bioactive preparations Methyure and Ivine (10-7 М) used by seed soaking caused a further increase of H+-ATPse transport activity especially in the presence of NaCl whereas H+-PPase one was not changed. Methyure effect in these experiments was more pronounced. Obtained results demonstrated participation of tonoplast H+-pumps in plant adaptation to NaCl which can be realized by amplification of Na+-H+ antiporter energization. An important role of vacuolar H+-ATPase in growth and adaptation processes in plants has been proved.
Effect of adaptogenic preparations on Na(+)/H(+)-antiporter function in plasma membrane of corn root cells under salinity conditions
N. O. Kovalenko, Zh. I. Bilyk, T. A. Palladina
Kholodny Institute of Botany, National Academy of Sciences of Ukraine, Kyiv;
e-mail: tatiana_palladina@ukr.net
Salinity is a hard stress factor for plant organisms which negative effect is caused chiefly by sodium toxic for plants. Plant cells try to remove Na+ from their cytoplasm outside and to vacuolar space by secondary active Na+/H+-antiporters. Their functions can be intensified by gene engineering methods however we try do it with the help of non-toxic bioactive preparations. A comparison of their effect on the plasma membrane of Na+/H+-antiporters was carried out on corn seedling roots of Zea mays L. exposed at 0.1 M NaCl. Before we have established that Methyure used by seed pretreating possesses a high salt protective ability as against Ivine. It was found that without NaCl exposition Na+/H+-antiporter activity in root plasma membrane was nearly unnoticeable but increased slightly with seedling age. Methyure and Ivine did not influence its activity in control root seedling. One day 0.1 M NaCl exposition evoked a considerable increasing of Na+/H+-antiporter activity and its gene expression but these effects disappeared at 10 day NaCl exposition. Methyure use reinforced Na+/H+-antiporter activity and prolonged it at NaCl exposition without effect on its gene expression whereas Ivine effects on these indexes were insignificant. Obtained results showed that the salt protective capability of Methyure is connected with plasma membrane Na+/H+-antiporter activation which is realized on molecular level.