ORIGINAL ARTICLE

Features of GABA-transaminase Functioning in Zea mays L. Leaves Under Salinity

Salt stress has a significant effect on plants, causing a whole range of changes in metabolism. Unfortunately, the mechanisms that ensure the adaptive response of cells in response to salinity have not been sufficiently studied. The study examined changes in the functioning of one of the enzymes of the anaplerotic pathway of the Krebs cycle - GABA shunt - GABA transaminase (GABA-T, EC 2.6.1.19). It has been shown that salt stress caused by incubation of corn seedlings in a 150 mM sodium chloride solution causes activation of GABA transaminase (GABA-T, EC 2.6.1.19). The established increase in GABA-T enzymatic activity in the first hours of incubation in saline solution reaches a maximum at 3 hours of incubation. At the same time, differences are observed in the expression profilees of the GTA-1 and GTA-2 genes, which encode this enzyme in the maize genome. Salinity in the first three hours induces an increase in the expression of the GTA-1 GABA-T gene, while the GTA-2 gene demonstrates an increase in transcriptional activity from 6 to 12 hours of the experiment. An increase in GABA-T enzymatic activity under salinity indicates activation of the GABA shunt to maintain the energy metabolism of the plant cell under stress conditions.