Cloning And Expression Analysis Of CgbZIP Gene Based On Transcriptome Of Chrysanthemum Grandiflora Under Salt Stress

Chysanthemum×grandiflora is one of the most important ornamental chrysanthemum species in the northern part of the country.It has strong resistance,rich flower color,concentrated flowering period,and dense flowers,low plant height and easy management.In this study,high-throughput transcriptome sequencing technology was used to sequence the transcriptome of salt-stressed Chysanthemum×grandiflora leaves and their controls.Through the functional annotation and metabolic pathway analysis of differentially expressed genes,the molecular mechanism of salt stress in response to salt stress was explored.The gene of bZIP transcription factor was screened and screened from the transcriptome sequencing library,and the full length of the open reading frame and the conserved domain were cloned.The full length was named CgbZIP.The gene is 1073 bp in length and encodes 339 amino acids.Real-time fluorescence quantitative analysis of this gene can respond to both salt stress and ABA stress,suggesting that it has an expression regulation effect on the resistance of Radix.The main findings of this paper are as follows:1.The salt-stressed Radix and its control materials were used to sequence the transcriptome using Illumina Hiseq2500 high-throughput sequencing platform.60370448 and 71415448 clean reads were obtained respectively.45591 Unigenes were obtained by sequence splicing.724 bp.There are 37,765 Unigenes annotated in seven databases(COG,GO,KEGG,KOG,Pfam,Swiss-Prot,NR).2.Real-time quantitative PCR was used to detect the expression of CgbZIP gene in Rhizoma radicans and leaves under three different abiotic stresses.The results showed that CgbZIP gene had obvious response to salt,drought and ABA stress.There is a difference in the amount of expression in roots and leaves.3.The complete open reading frame of 1020 bp CgbZIP gene was cloned by PCR.The plant expression vector was constructed by ligating it with PBI121-GFP vector and transferred into Agrobacterium.The tobacco was infested by leaf disc method,and Kanamycin was used.9 transgenic plants were obtained by screening and PCR.4.Subcellular localization of the constructed PBl121-CgbZIP-GFP plant expression vector revealed that the CgbZIP gene was expressed on the nucleus.5.Through the salt stress and drought stress treatment of three transgenic tobacco lines and wild-type strains,the phenotypes were observed and their physiological indexes were observed.The results showed that the transfer of CgbZIP gene effectively enhanced the resistance of tobacco to salt stress and drought stress.