Overexpression Of AtCDPK1Driven By Constitutive And Inducible Promoters Enhances Tolerance To Drought And Salt Stress Of Thetransgenic Arabidopsis

CDPKs(calcium-dependent protein kinase, CDPKs or CPKs) are a family of serine/threonine protein kinases that are unique to plants. Calcium ions as one of the second messengers plays an important role in intracellular. CDPKs are receptor proteins and effector proteins of Ca2+and were induced by biotic and abiotic stress. CDPKs have modulated many plant growth signals and various reactions, and play an essential role in the signal transduction pathways. In this study, we use Arabidopsis thaliana wild type,35S::CDPK1and RD29A::CDPK1k overexpression transgenic homozygote plants as materials, to provide the evidences that AtCDPK1has important functions in Arabidopsis tolerance to drought and salt stresses. The results are as following:1. Further analysis on the35S::CDPK1lines revealed that the seeds of the35S::CDPK1lines had higher germination rate than the wild type under100mM and150mM NaCl treatment. The four-week-old35S::CDPK1plants showed stronger tolerance to drought and salt stress than the wild type. And the bolts of the wild type were inhibited after drought and salt stress, while those of the35S::CDPK1lines were not affected.2. The expression levels of several drought responsive genes increased in35S::CDPK1plants compared with wild type under drought stess. And the expression levels of some salt responsive genes elavated in35S::CDPK1plants compared with wild type under250mM NaCl treatment.3. The RD29A-promoter driven CDPK1k recombinant plamid (RD29A::CDPK1k) was constructed and transformed into wild type Arabidopsis thaliana by agrobacterium-mediated infection. Totally11transgenic homozygotes were obtained by gentamycin selection. And the expression levels of CDPK1genes elavated in RD29A::CDPK1k plants compared with wild type drought treatment.The survival rate of the RD29A::CDPK1k plants was higher than that of the wild type under drought and salt stress.