| Temperature is one of the key factors affecting the germination ability of wheat.High temperature will affect the germination ability of wheat grains at the sowing stage and reduce the emergence rate.This study intends to identify typical high temperature sensitive and insensitive varieties through germination experiments on 344 wheat varieties.By sequencing the transcriptome of the high temperature sensitive variety(Gaoyou 0213),the gene expression and metabolic pathway changes under high temperature stress were analyzed at an overall level to identify the key factors that affect the seed germination ability and to construct the regulatory networks under high temperature..The main results are as follows:1.The germination experiments were performed on 344 wheat varieties under high temperature conditions.It was found that the germination ability of different varieties was significantly different at high temperatures,with germination rates between 0-100%.Through association analysis,a total of 10 significant SNPs were detected in the short arm of the 3A stained 7.6-11.1Mb region,the short arm of the 2A chromosome at 11.5Mb and the short arm of the 5A chromosome at 38.2Mb,explaining 6.06-10.64% of the phenotypic variation.The results indicate that there may be genes related to these sites that affect the ability of grain germination at high temperatures.2.RNA-seq sequencing was performed using the high-temperature-sensitive variety Youyou 0213,and a total of 7.88 Gb of data was obtained.Contains 108059 genes,of which52,521 have significant expression differences,and 41,120 genes are annotated into the Nr library.There were 11,867 genes annotated into the GO pathway,and the classification of GO functional annotation showed that these genes were mainly enriched in pathways such as binding,metabolism,and catalytic activity.6968 genes were annotated into the KEGG pathway.Annotation of the KEGG pathway indicated that genes are mainly enriched in metabolic pathways such as metabolic pathways,plant hormone signal transduction and amino acid biosynthesis,indicating that these pathways may affect seed germination at high temperatures Play an important role in the process of competence.3.Differential trend analysis was used to obtain the expression change pattern of all genes under high temperature stress,and then statistical analysis was performed on genes with large expression changes under high temperature stress.The results showed that there were 26 genes with more than 15-fold difference in gene expression and 3 with more than 25-fold difference.Genes such as histone(H2A),heat shock transcription factor(HSF),heat shock protein(HSP),zinc finger protein and so on all showed significant differential expression.The more typical genes are 1BS＿0165210 and 1A＿0048030.The 1BS＿0165210 gene belongs to the wheat H2 A gene family.Based on bioinformatics methods,the genetic structure,chromosomal location,and stress-related cis-elements and gene expression levels of wheat H2 A family genes were analyzed.4.1 1A＿0048030 gene is a heat shock transcription factor,which interacts with heat shock protein,molecular chaperone,active oxygen scavenging enzyme and other functional protein genes.Analysis of the gene based on bioinformatics methods showed that the1A＿0048030 gene exists in multiple GO pathways related to germination dormancy and stress resistance,and has multiple homeopathic elements related to abiotic stress.Through gene expression analysis and q RT-PCR detection,it was confirmed that the expression of1A＿0048030 gene increased significantly after 2h of high temperature stress(the critical period from the germination to the dormancy of the grain).In order to further identify the function of this gene,a gene editing vector of 1A＿0048030 was constructed and has been transferred into the wheat variety Fielder to obtain a transgenic seedling. |
PDF Full Text Request