Functional Analysis Of CBL1 Gene From Ammopiptanthus Mongolicus (Maxim.) Cheng F

The Ca²⁺ is one of the important signal components responsive to environmental stress in plants.It plays the important role in disease-resistant,the anti-insect and adapts in the non-biological coercion response.There are hree kinds of calcium signaling system identified in plant cell: Ca²⁺/CDPK,Ca²⁺/CaM and Ca²⁺/CBL.They are closely related with the adverse circumstance coercion signal transduction.They may unify with the calcium ion,cause the protein conformation change to activate the protein function and composes many signaling systems together with the downstream protein interaction.They are regulating plant growth and participateing in stress signal transduction.The CBL(calcineurin B-like) protein family represents a unique group of calcium sensors in plants.A member of this family,CBL1,can be induced by multiple stresses,positively enhanced the tolerance to salt and drought.At present,the CBL1 related research mainly concentrates on the mode plant,Arabidopsis thaliana.Ammopiptanthus mongolicus,as the unique evergreen shrub in northwest of Chinese hungriness and hemieremion area,develops high endurance to drought,salt,and low temperature.In this study,we isolated the CBL1 gene from Ammopiptanthus mongolicus,and the CBL1 gene was transfer to tobacco by Agrobacterium-mediated method.Gene function of CBL1 from Ammopiptanthus mongolicus under abiostress was analyed.We constructed 2 plant expression vectors:PBI121-CaMV35S-CBL1 and PBI121-RD29A-CBL1. Then we transformated tobacco by the Agrobacterium-mediated transformation method and obtained the transgenic plant after Kanamycin screening.And we cultivated 2 weeks tissue culture seedlings (including transgenic plant and control plant) to the soil,after harvested the seeds,planted the T1 generation of tobacco seeds on MS and MS+Ka medium,detected germination rate,the fresh weight, growing trend of T1 generation.Then cultivated 3 weeks tissue culture seedlings(including transgenic plant and control plant) to the soil,after 4 weeks carring on the gradient treatment with drought,salty and cold.We determined a series of data,for example,photosynthesizes rate,the chlorophyll content, the electrolyte leakage rate,WUE,Chlorophyll fluorescence analysis and so on,contrasted with the control plant,Under the adverse circumstance condition the transgenic plant had lower cell membrane damage degree and higher ability to utilize the energy of light and water.The latent active centers of PSâ…¡was not suffered injury and its Electron transfer activity was higher,Through enhancing the non-radiative heat dissipation,consuming PSâ…¡Absorption surplus energy of light to protect the reaction center of PSâ…¡from the photooxidation injury which caused by absorbs many energies of light.Thus we obtained the conclusion:The transgenict plant has higher tolerance to the drought,salt and the low temperature than the control plant.Our results indicated that the CBL1 gene of Ammopiptanthus mongolicus is the positive adjustment factor under the drought,salt and cold condition.