| Soil salination is one of the main factors restricting the productivity of agricultural and forestry resources.To adapt to the environment,plants slow salt damage by series responses such as initiating gene expression,altering the physiological metabolism and morphological structure.A growing number of studies suggest that C2H2 zinc finger proteins(ZFPs)play important roles in the regulatory networks of plant response to salt stress.Nowadays,the research on C2H2 ZFPs mainly focuses on Q-type ZFPs in Arabidopsis,rice,wheat,cotton and other crops,while the understanding of non-Q-type C2H2 ZFPs is very limited.Previously,109 C2H2 ZFPs,Ptr ZFPs,were identified from Populus trichocarpa,62 of which encode the proteins as non-Q-type ZFPs.Identification and analysis of the function of salt-resistant C2H2 zinc finger protein genes will provide important information for a deeper understanding of the molecular mechanisms of poplar in response to abiotic stress.Identification of the salt-resistant C2H2 zinc finger protein genes will provide important information for a deeper understanding of the molecular mechanisms of poplar in response to abiotic stress.In this study,through the analysis of previous transcriptome sequencing results,we obtained a C2H2 zinc finger protein gene significantly up-regulated after salt stress treatment in the xylem of Populus davidiana×P.bolleana,and this domain does not have the Q-type characteristic motif "QALGGH",which is named PdbZFP26 because it is consistent with the Ptr ZFP26 sequence in Populus trichocarpa.Then we analyzed the function and expression mode of PdbZFP26 gene.The main work and results are as follows:1、Bioinformatics analysis of PdbZFP26 gene showed that PdbZFP26 gene encoded 686(22 kinds)amino acids.PdbZFP26 is a typical C2H2 zinc finger protein.Phylogenetic tree shows that it is a C-type zinc finger protein.Sequence alignment results show that its zinc finger structure does not contain "QALGGH" motif,and PdbZFP26 subcellular localization is in the nucleus.2、The expression pattern analysis showed that PdbZFP26 is highly expressed in stems,mainly in xylem(including vascular cambium);except salt stress,both ABA and BRs cause the upregulation of PdbZFP26.3、In order to verify the function of PdbZFP26,we successfully constructed a new vector containing the gene of PdbZFP26.We first treated transgenic Populus davidiana×P.bolleana with Na Cl and found that the growth state of transgenic Populus davidiana×P.bolleana tissue culture seedlings and transplanted seedlings under salt stress was better than that of wild-type Populus davidiana×P.bolleana.Then we measured some antioxidant indexes,chlorophyll content and leaf water loss rate of transgenic Populus davidiana×P.bolleana.It was found that under salt stress,the activity and chlorophyll content of some antioxidant related protective enzymes in transgenic Populus davidiana×P.bolleana were higher than those of wild-type Populus davidiana×P.bolleana,while some indexes to measure the degree of plant peroxidation were lower than those of wild-type Populus davidiana×P.bolleana.It can be seen that the transgenic Populus davidiana×P.bolleana with PdbZFP26 gene can improve the salt tolerance of transgenic Populus davidiana×P.bolleana by increasing the activity of antioxidant enzymes,reducing the accumulation of peroxides and enhancing photosynthesis.4、In order to further verify the function of PdbZFP26 gene,we obtained Arabidopsis transformed with PdbZFP26 gene by inflorescence immersion method.After salt treatment,it was found that PdbZFP26 gene could improve the root length and seedling growth state of Arabidopsis seedlings under salt stress.The results of leaf staining also showed that PdbZFP26 gene could reduce the negative effect of salt stress on the growth of Arabidopsis.Therefore,we speculate that PdbZFP26 can improve the tolerance of transgenic plants to salt stress by increasing antioxidant enzyme activity and reducing the accumulation of peroxides. |
PDF Full Text Request