Department of the Molecular Mechanisms of Cell Metabolism Regulation, Kukhar Institute of Bioorganic Chemistry and Petrochemistry, The National Academy of Sciences of Ukraine, 02660, Murmanska str., 1, Kyiv, Ukraine.
Laboratory of Steroid Chemistry, Institute of Bioorganic Chemistry, The National Academy of Sciences of Belarus, 220141, Kuprevich str., 5, Minsk, Belarus.
Steroids. 2019 Jul;147:28-36. doi: 10.1016/j.steroids.2019.04.002. Epub 2019 Apr 11.
Using Arabidopsis thaliana wild type (WT) plants and diacylglycerol kinase knockouts (single mutants - dgk3, dgk1, dgk6; double mutants - dgk3dgk7, dgk5dgk6, dgk1dgk2) we observed that the inhibitor of brassinosteroid (BR) biosynthesis, brassinazole (BRZ), drastically decreased germination of dgk mutants under salt stress, while BRZ co-administration with 24-epibrassinolide (EBL) partially improved germination rates. We also observed a statistically significant decrease in alternative and cytochrome respiratory pathways in response to BRZ treatment under salinity conditions. We showed that production of the lipid second messenger phosphatidic acid (PA) is impaired in dgk mutants in response to EBL treatment and inhibitor of diacylglycerol kinase (DGK) - R59022. This study demonstrates that dgk mutants possess lower germination rates, lower total respiration rates, an alternative respiratory pathway and PA content under optimal and high salinity conditions in response to EBL treatment comparing to WT plants.
我们使用拟南芥野生型（WT）植物和二酰基甘油激酶敲除体（单突变体-dgk3、dgk1、dgk6；双突变体-dgk3dgk7、dgk5dgk6、dgk1dgk2）发现，油菜素内酯（BR）生物合成抑制剂油菜素唑（BRZ）在盐胁迫下极大地降低了 dgk 突变体的萌发率，而 BRZ 与 24-表油菜素内酯（EBL）共同给药部分提高了萌发率。我们还观察到，在盐胁迫条件下，BRZ 处理会导致替代和细胞色素呼吸途径的统计学显著下降。我们表明，dgk 突变体在 EBL 处理和二酰基甘油激酶（DGK）抑制剂 R59022 处理下，脂类第二信使磷脂酸（PA）的产生受损。本研究表明，与 WT 植物相比，dgk 突变体在最佳和高盐条件下对 EBL 处理的萌发率、总呼吸率、替代呼吸途径和 PA 含量较低。
