The Effect Of EATP On Stress Tolerance Of Arabidopsis Thaliana

In recent years,eATP had been found existing in extracellular space of plant cells,eATP is involved in modulating growth,development and stress tolerance of plant cells.In order to explore the mechanism of eATP regulated main root growth and the effect of eATP on seed germination and seedling growth of Arabidopsis thaliana under various stress(drought,salt, chilling,freezing and high temperature).Conventional methods of plant physiology was applied to investigate the effects of ATP on main root growth rate and the seed germinal percentage,seedling livability and development of seedling.The results showed that both ATP and ADP inhibited growth of main roots of Arabidopsis thaliana,while AMP did not affect the process.The eATP-induced inhibition of root growth was supressed in heterotrimeric G protein null mutant and promoted in G protein over-expression strains,indicating that heterotrimeric G protein participates in signal transduction of eATP induced root growth.There is not difference in root growth rate between wild type and null mutant of NADPH oxidase,indicating that ROS maybe not participating in eATP induced root growth inhibition.Under various stress condition,there was no significant difference in seed germination rate,seedling livibility and development of seedling before and after ATP treatment. Indicating that eATP can not promote the tolerence of Arabidopsis to these stresses.Our results confirms that eATP inhibit main root growth of Arabidopsis thaliana,G protein participates in this process.ATP can unlikely promote stress tolerance of Arabidopsis to drought,salt,chilling,freezing and heat stress.