| A key to the transfer of certain plants from the vegetative growth stage to the reproductive development stage is vernalization.The typical biennial crop of sugar beet must be induced by vernalization and long-day illumination to ensure convulsions and flowering.Then complete the reproductive growth process.The transition from vegetative growth to reproductive development is a complex process that requires a combination of multiple environmental factors and endogenous signals.At present,vernalization research mainly focuses on the model plant Arabidopsis,and there are relatively few studies on sugar beet.Long-chain non-coding RNAs(lncRNAs)are noncoding RNAs over 200 nt in length,and many studies have demonstrated that lncRNAs can interact with target genes by cis or trans regulation,thereby regulating gene expression.However,lncRNA in plants has not been fully investigated,and two types of lncRNA for vernalization have only been identified in Arabidopsis.This study hopes to exploit the differentially expressed lncRNA during the vernalization of sugar beet by high-throughput sequencing to understand the role of lncRNA during vernalization.The research results are as follows:A total of 36,445 mRNAs and 7421 lncRNAs were identified in this study.Among them,there were 785 mRNAs with significant differences;292 had significant difference in lncRNA.The 7421 lncRNAs included 5827 intergenic lncRNAs(lincRNAs),769 intron lncRNAs,294 antisense lncRNAs(lncNAT)and 531 other lncRNAs.By comparing the structural features and expression levels of lncRNA and mRNA,it was found that lncRNA was lower than mRNA in terms of sequence length,ORF length and exon number,and its expression level was also significantly lower than that of mRNA.Bioinformatic analysis of differentially expressed mRNA revealed that these mRNAs are primarily involved in processes such as nucleic acid binding,nuclear and protein binding,and metabolic pathways such as RNA transport,mRNA monitoring pathways,and phytohormone signaling.Five mRNAs involved in flower development were also found.For 292 differentially expressed lncRNAs,763 target genes were predicted.Through GO and KEGG analysis,these target genes were mainly involved in ATP binding,protein binding,plant hormone signal transduction and endocytosis,and four target gene sequences involved in vernalization were found and their corresponding 120 lncRNAs.By performing protein interaction analysis on the proteins encoded by the four target genes,a protein FL1 that has been shown to participate in vernalization was found.A co-expression network of lncRNA and its target genes was constructed,and its expression in different stages of vernalization was analyzed.It was found that their changes in expression levels during different periods of vernalization were not completely consistent.This study predicted that 40 lncRNAs are targets for their corresponding 30 miRNAs.Combined with miRNA target analysis,26 lncRNAs that can act as ceRNAs were predicted,involving 201 mRNAs,and a lncRNA-miRNA-mRNA expression network was constructed.Bioinformatics analysis of these mRNAs revealed that they are mainly involved in DNA binding,hormone response,auxin-activated signaling pathway and protein ADP-ribosylation,and a gene associated with vernalization,It corresponds to two miRNAs and one lncRNA.In this study,the lncRNA of sugar beet was compared with the lncRNA of Arabidopsis thaliana by local blast.A total of 59 beet lncRNAs were compared to 37 Arabidopsis lncRNAs.The sequence of the lncRNA was found to be less conserved by comparison. |
