Analysis Of Genetic Regulatory Network In Response To High Temperature Stress In Maize Based On Transcriptome Sequencing

Maize is an important food and forage crops for between China and the world,but its yield and quality are often affected by various biotic and abiotic stresses,especially the extreme high temperature that has frequently occurred in recent years.Production has caused a great impact,which has become one of the main adversity factors leading to the decrease of maize yield and quality.In recent years,it has been found that noncoding RNA molecules such as lncRNA and miRNA play an important role in the regulation of abiotic stress,but the specific mechanism of noncoding RNA molecules in the regulation of high temperature stress,which is still unclear.In this study,the maize inbred line CM1 was used as material to screen lncRNA and miRNA in response to high temperature stress and identify key target genes for their regulation based on high-throughput sequencing technology.On this basis,a genetic regulatory network based on the response to high temperature stress in maize was constructed,which laid a foundation for further study of revealing the molecular regulatory mechanism of maize high temperature tolerance,the main research results are as follows:1.A total of 53,249 lncRNAs,including 259 known lncRNAs and 52,990 novel lncRNAs,were identified by high-throughput sequencing of maize inbred line CM1 as the research material,including 95.56%of lincRNA,1.97%of antisense_lncRNA and 2.47%of intronic_lncRNA.2.The expression and structural characteristics of lncRNA and mRNA were compared,and the expression level of identified lncRNA was generally lower than that of mRNA,with large differences in the number of exons and transcript length.Through differential expression analysis,a total of 993 differentially expressed lncRNAs were identified(570 up-regulated and 423 down-regulated)and 13,160 differentially expressed mRNAs transcripts(8,950 up-regulated and 4,210 down-regulated).3.Through screened and identified the cis and trans regulated target genes of lncRNA with differential expression,that was obtained 956 cis and 8927 trans differentially expressed target genes respectively through the differential expression screening of target genes.and a total of 953 differentially expression of target genes was used GO and KEGG enrichment analysis,which found some biological pathways that may be related to the response to high-temperature stress.4.Through sRNA high-throughput sequencing,a total of 340 miRNAs were obtained,of which 215 are known miRNAs belonging to 40 families,and the number of miRN As with length of 21nt is the most abundant;Meanwhile,125 novel miRNAs were identified.5.Identified 35 significantly differentially expressed miRNAs,21 of which were up-regulated and 14 were down-regulated.Through degradome sequencing,Among differentially expressed miRNAs,the expression levels of known miRNAs are generally higher than those of novel miRNA members.6.Through degradome sequencing,a total of 174(527 transcripts)target genes of 115 miRNAs were identified,which were mainly transcription factor families of types.A total of 17 target genes were identified among 35 significantly different miRNAs.7.Based on the results of lncRNA、mRNA and miRNA regulate relationship and enrichment analysis of important target genes,the genetic regulatory network of maize inbred line CM1 under high temperature stress was constructed by using the software of Cytoscape,which laid an important foundation for further revealing the molecular regulatory mechanism of maize high temperature tolerance,and provided a new idea for the creation of new maize germplasm with high temperature tolerance.