Microbial Technologies Division, Council of Scientific and Industrial Research-National Botanical Research Institute (CSIR-NBRI), Rana Pratap Marg, Lucknow 226001, India; Department of Botany, University of Lucknow, Lucknow 226007, India.
The Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen 72076, Germany.
Microbiol Res. 2024 Dec;289:127890. doi: 10.1016/j.micres.2024.127890. Epub 2024 Aug 31.
This study investigates the molecular mechanisms underlying salt stress responses in plants, focusing on the regulatory roles of OsNAM2, a gene influenced by the plant growth-promoting rhizobacterium Bacillus amyloliquefaciens (SN13). The study examines how SN13-modulated OsNAM2 enhances salt tolerance in Arabidopsis through physiological, biochemical, and molecular analyses. Overexpression of OsNAM2, especially with SN13 inoculation, improves germination, seedling growth, root length, and biomass under high NaCl concentrations compared to wild-type plants, indicating a synergistic effect. OsNAM2 overexpression enhances relative water content, reduces electrolyte leakage and malondialdehyde accumulation, and increases proline content, suggesting better membrane integrity and stress endurance. Furthermore, SN13 and OsNAM2 overexpression modulates essential metabolic genes involved in glycolysis, the pentose phosphate pathway, and the tricarboxylic acid cycle, facilitating metabolic adjustments crucial for salt stress adaptation. The interaction of OsNAM2 with SUS, facilitated by SN13, suggests enhanced sucrose metabolism efficiency, providing substrates for protective responses. Additionally, OsNAM2 plays a regulatory role in the ABA signaling pathway through significant protein-protein interactions like with AFP2. This study highlights the intricate interplay between SN13-responsive OsNAM2 and key signaling pathways, suggesting strategies for enhancing crop salt tolerance through targeted genetic and microbial interventions.
本研究探讨了植物耐盐响应的分子机制，重点研究了 OsNAM2 基因的调控作用，该基因受植物促生根际细菌解淀粉芽孢杆菌（SN13）的影响。本研究通过生理、生化和分子分析，研究了 SN13 调节的 OsNAM2 如何通过增强拟南芥的耐盐性。与野生型植物相比，OsNAM2 的过表达，特别是与 SN13 接种一起，在高 NaCl 浓度下提高了种子萌发、幼苗生长、根长和生物量，表明存在协同作用。OsNAM2 的过表达增加了相对含水量，降低了电解质泄漏和丙二醛积累，增加了脯氨酸含量，表明膜的完整性和应激耐力更好。此外，SN13 和 OsNAM2 的过表达调节了参与糖酵解、戊糖磷酸途径和三羧酸循环的必需代谢基因，促进了适应盐胁迫的代谢调整。在 SN13 的作用下，OsNAM2 与 SUS 的相互作用表明蔗糖代谢效率的提高，为保护反应提供了底物。此外，OsNAM2 通过与 AFP2 等重要的蛋白质-蛋白质相互作用，在 ABA 信号通路中发挥调节作用。本研究强调了 SN13 响应的 OsNAM2 与关键信号通路之间的复杂相互作用，为通过靶向遗传和微生物干预提高作物耐盐性提供了策略。
