Water deficit induces changes in H⁺-ATPase activity and its gene expression inZea maysL. roots

Abstract

We investigated the functioning and the gene expression of H + -ATPase in the microsomal fraction enri ched with plasmalemma vesicles isolated from roots of two Zea mays cultivars: Dostatok (drought resistant) and Pereyaslivskiy (moderately tolerant to drought). Both cultivars grew during 21 days under the optimal water supply (soil moisture -70 %, control) and during 10 days under the water deficit conditions (soil moisture -30 %, experiment). An increase in the H + -ATPase hydrolytic activity in both cultivars under the water stress has been detected under drought. The enzyme hydrolytic activity is increased by twice in Dostatok and by1.3 times in Pereyaslivskiy. The H + -ATPase gene expression levels in both cultivars also increased under water deficit. It is shown that, in roots of both maize cultivars, the increase of four isoforms of H + -ATPase gene expression correlates with the increase of the hydrolytic

PIP2;1 aquaporin gene expression in maize hybrids different for drought tolerance to water deficit

“…In our experiments, the genotype-specific regulation of PIP aquaporin gene expression was also revealed in responses of investigated maize hybrids different for drought tolerance to water deficiency. In addition, up-regulation of PIP2;1 aquaporin gene in maize drought-resistance hybrid Dostatok under 30 % substrate moisture correlated with the essential enhancement in the H + -ATPase hydrolytic activity, which was higher about three times in comparison with that in more drought-sensitive hybrid Pereiaslavskii [15]. The obtained data allow us to consider the PIP2;1 aquaporin gene expression as a molecular marker in maize breeding for drought tolerance.…”