The Response Mechanism Of Vacuolar H～+-ATPase To Salt Stress In Elymus Nutans

Salt stress has been became one of the main factors threatening agricultural productivity. Elymus nutans were subjected to a range of NaCl treatments (150mM to 400mM) for 24h. High-purity tonoplast vesicles and RNA from E.nutans were isolated and the V-ATPase activity and the expressional change under salt stress were measured. The results showed that ATP-hydrolytic and H+-transport activities were activated by salt stress in E. nutans leaves and roots,and a similar trend was established for Na+ content. Salt stress induced the expression of V-ATPase subunit A both in leaves and roots as determined by Western blot analysis; expressional signal of subunit B in leaves increased under 150mM,200mM,250mM NaCl while there were no significant changes under 300mM,350mM,400mM NaCl,subunit B in roots less affected by salt stress than subunit A. Northern blot analysis showed increased levels of V-ATPase subunit A mRNA in roots with higher-concentration salt treatments,while there were no changes in leaves. In this study,we measured the change in E. nutans root V-ATPase at the physiological,chemical and genetic levels to understand how V-ATPase responds to salt stress to accommodate the saline environment. The results provide experimental support for plants elucidating environmental signal congnition and conduction,conducing to claritify the accomdating mechanism to salinity in plants,and provide theoretical support for screnning salt resistance breeding and controlling land desertification and improving the genetic background of Triticum crops.