Validation of targeted relationships of ciRNA803( lncRNA MSTRG.19726)-oar-let-7a-CPEB1 ceRNA networks, key to ovarian development in monotypic and multitypic sheep based on whole transcriptome sequencing

Because the reproductive efficiency of sheep depends on the number of ovulation by their ovaries, which is closely related to the "follicular wave" of the estrus cycle, especially its dominance. Like other mammals, the ovine ovary goes through the "wave" development process of "collection - selection - dominance - mature ovulation" during the estrus cycle after it enters sexual maturity. Previous studies at home and abroad have shown that non-coding RNAs, including lncRNA, circRNA and miRNA, all play a core regulatory role in the development of mammalian ovary, among which lncRNA and circRNA have the "sponge" adsorption effect of miRNA, which can reduce the activity of miRNA and indirectly affect the regulatory network of target gene mRNA, thus becoming the focus of transcriptional regulation of non-coding RNA. Therefore, the analysis of the regulatory mechanism of ceRNA network in the process of ovarian development has important theoretical guidance for improving the reproductive efficiency of animals. In this study, multiple fetal sheep breeds (small tail Han Sheep) and single fetal sheep (Ujumuqin Sheep), which were widely raised in Jilin Province, were analyzed to obtain RNA-seq data during estrus, obtain comprehensive mRNA, miRNA, lncRNA and circRNA expression profiles of sheep ovaries, and construct ceRNA network. Then, the key genes and molecular regulatory mechanisms controlling ovine ovarian development were analyzed. The results of this study will provide a theoretical basis for fully understanding the reproductive biological characteristics of sheep and guiding the application of efficient breeding techniques such as the breeding of new breeds of multi-foamed sheep and frequent lambing of sheep.