Molecular Mechanism Of ABA Pathway Of Zoysia Japonica In Response To Salt Stress

Soil salinization is one of the natural adversities encountered by lawn grass,Zoysia is a kind of warm-season turfgrass with strong salinity tolerance.This study starts from the analysis of the transcriptional group of Zoysia japonica salt stress,screening and identy the genes related to salt stress response,revealed the molecular mechanism of the resistance of Zoysia japonica to salt stress,from the level of transcriptome.It will provide a theoretical basis for molecular breeding of salt tolerance of plant.Studies have shown that ABA pathway is closely related to salt tolerance.In this study,we investigated the gene of ABA biosynthetic pathway and its signal transduction pathway in Zoysia japonica salt stress transcript group.The results shows,a total of 1455 Unigenes can be compared to the GO annotations,and set up 73 responses,containing 798 up-regulated Unigenes and 647 down-regulate Unigenes.We screened out all the response to gene annotations from Biological Process of GO annotations,and found a total of 65 Unigenes were response to abscisic acid.It is shown that ABA plays an important role in regulating salt stress.The KEGG annotation demonstrated that ABA synthesis can be traced back to the genes involved in glycolysis,terpenoid biosynthesis and carotenoid biosynthesis.The synthesis of glycolysis has 50 pathways.We traced back to 421 Unigenes enrichment in 24 pathways.The terpenoid synthesis pathway generally has 47 pathways,which we traced back to 106 Unigenes enriched at 24 pathways.The carotenoid synthesis pathway of 50 pathways,here we traced back to 35 Unigenes enriched in 16 pathway.According to the DEGs and their expression changes,five Unigenes were selected,their gene ID are comp223195_c0,comp2243 10_c0,,comp178903_c0,comp210872_c0 and comp235482_c0,and we successfully verified the reliability of RNA-Seq results,by real-time PCR.The gene expression results are as follows:1)The expression of comp223195_c0 revealed difference between leaves and roots,and revealed significant difference in the T3,which may be related to the ABA content in leaves,indicating that a large amount of ABA was synthesized in the leaves.The expression of root was correspondingly increased.2)The expression of comp224310_c0 gene in T1 was the highest,and the expression was up-regulated,but had lower expression and down-regulated in root.Therefore,we hypothesized that quantity of PYR/PYL/RCAR protein regulated by this gene in the whole process of stress.3)Two genes comp210872_c0 and comp178903_c0 in the leaves and roots of PP2C regardless of the expression trend showed down mode,which first decreased the expression of comp 178903_c0 in the leaves after the rise,contrary to the root of the regulation mode,therefore may not belong to a class of PP2C gene,or in the lower period involved in the process of activation of SnRK2.4)The expression of SnRK2 gene comp235482_c0 was up-regulated,and it was speculated that osmotic stress could activate the SnRK2 gene expression,and then regulate the stress tolerance of plants.