Study On The Sexual Type Differentiation Of Cucumber Induced By Carbon Ion Irradiation And Its Molecular Mechanism

Cucumber is one of the most important vegetable crops in the world,and its all-female breeding is the ultimate goal of cucumber breeding.The key issue of all-female breeding is to study and excavate the genes related to cucumber sexual differentiation,which will provide relevant theoretical basis for the sex regulation,genetic improvement and development of high-quality new varieties of cucumber.In this paper,regarding cucumber seeds of different sex types after carbon ion irradiation as the research object,high-throughput sequencing technology was used to sequence the transcriptomes of four cucumber flower bud samples: all male plants,strong female plants,male plants in strong female plants,and female×male.25 268 genes were obtained through pairwise comparison,from which differentially expressed genes were screened,and GO functional classification and KEGG pathway enrichment analysis were performed.The study found that cucumber differentially expressed genes participated in or encoded 137 signal pathways.Among these signal pathways are synthetic pathways and signal transduction pathways related to sexual differentiation.Among them,5 genes were differentially expressed in the ethylene synthesis pathway,4 genes were differentially expressed in the auxin synthesis pathway,8 genes were differentially expressed in the abscisic acid synthesis and signal transduction pathways,14 genes were differentially expressed in the auxin signal transduction pathway.Besides,6 genes were differentially expressed in the cytokinin synthesis and signal transduction pathways,and 7 genes were differentially expressed in the brassinolide synthesis and signal transduction pathway.The related genes involved in sex type differentiation synthesis and signal transduction were found by high-throughput sequencing analysis.Real-time Quantitative PCR technology was used to verify the differential genes related to some sexual type differentiation.The results showed that the gene expression levels were consistent with the transcriptome sequencing results,which confirmed the accuracy of the transcriptome data.Molecular marker research was carried out based on the transcriptome data,and 7 635 SSR marker information and annotation information of SNP variant sites were obtained.It provides basic data information for the construction of cucumber genetic map,breeding of new varieties and genetic diversity research.According to the differential gene expression analysis,the new cucumber genes predicted by the transcriptome were screened,and novel.714,a new gene related to cucumber sex type was obtained.Through bioinformatics analysis,it was found that the gene has highly conserved plant self-incompatibility,and the mutation site of the gene was found.After structural analysis of the mutation site,it was found that it had an impact on the protein structure.It is speculated that this gene may work together with other genes in the process of cucumber selfing,and have an impact on the genotype differentiation of cucumber.All the research results above provide experimental and theoretical basis for mining the regulatory mechanism of cucumber sex-type differentiation-related genes,cloning and gene knockout of sex-type modification-related genes.