Identification Of Salt Stress Response Genes In Tartary Buckwheat Seedlings Based On Transcriptome

Tartary buckwheat is a nutritious miscellaneous grain crop.Planting Tartary buckwheat can not only meet its own food needs,but also bring considerable economic benefits.With the aggravation of soil salinization,the cultivation of Tartary buckwheat is facing great challenges.It is necessary to study the salt tolerance mechanism of Tartary buckwheat and improve the salt tolerance of Tartary buckwheat.In this study,the high-throughput sequencing platform Illumina Hiseq 2500 was used to sequence the salt-treated Tartary buckwheat seedlings,the transcriptome analysis was carried out,and the function of the assembled Unigenes was annotated.Then,the transcriptional differences between Tartary buckwheat control samples and salt stress treated samples were compared in order to determine the potential regulatory factors of Tartary buckwheat participating in salt stress response,and to provide theoretical basis for further understanding the regulation mechanism of Tartary buckwheat salt tolerance network..The main results are as follows:1.After treatment with 0.2 mol/L NaCl solution for 24 hours,the relative water content of Tartary buckwheat seedlings decreased from 85.28% to 83.52%,showing a significant difference(0.01 < p < 0.05).The relative conductivity content,malondialdehyde content,SOD activity and POD activity increased by 53.2%,25.9%,10%,40% and there were showing significant difference(p < 0.01).2.Functional annotations were performed on Unigene,where a total of 30500(52.65%),21064(36.36%),20859(36.01%),11791(20.35%),23445(40.47%),11206(19.34%)and20834(35.96%)Unigenes were annotated to theGenebank NR,Genebank NT,Pfam,KOG,Swiss-Prot,KEGG and GO databases,respectively.Unigene was divided into 56 GO subclasses in GO database.In KOG database,25 functional groups were divided into KEGG classification,while KEGG classification involved 273 metabolic pathways.3.The transcription factors that may be involved in salt response were predicted.And the 3107 Unigenes were identified as 93 transcription factor families,the largest proportion of which were C2H2,WD40-like and MYB-HB-like families.4.The differentially expressed genes were analyzed.Among the 455 differentially expressed genes,404 Unigenes were up-regulated after salt treatment,and 51 Unigenes were down-regulated after salt treatment.GO enrichment analysis showed that 363 differentially expressed genes were enriched in 25 GO subclasses.KEGG enrichment analysis showed that differentially expressed genes were enriched in metabolic pathways such as antigen treatment and presentation and protein processing in endoplasmic reticulum.5.By SSR sequence analysis,a total of 6176 potential SSR were identified to be distributed in 5455 Unigenes.The most abundant types of repeats were single nucleotide repeats and trinucleotide repeats,of which A / T sequences were the most frequently repeated.6.Fourteen differentially expressed genes were randomly selected and primers were designed to verify the high-throughput sequencing results by qPCR.It was found that the expression trend was basically consistent with that of transcriptome analysis,indicating that the sequencing results were accurate and reliable.7.Through homology analysis of differentially expressed genes and combined with the study of salt resistance related genes,62 genes which may be involved in salt response of Tartary buckwheat were screened.These genes are involved in the regulatory networks of protein kinases,phosphatase,heat shock proteins,ABC transporters,transferases,abiotic transcription factors and biological clocks.