Comparative Profiling Of Differentially Expressed MicroRNA Between The Follicular And Luteal Phases Ovaries Of Goats

In order to study the reproductive disease of goat breeders,this study studied miRNAs play a role in goat ovulation cycles.In this study,the high-throughput sequencing method was used to explore the regulation mechanism of miRNA in the ovarian ovulation cycle of the goat.By predicting the candidate target gene,the target gene of miRNA was enriched and analyzed by KEGG pathway to find out the relationship with goat reproductive disease and ovulation cycle regulation related to miRNA.The results will help to further understand explore the regulatory effect of miRNAs in the ovary ovulation cycle of goats and some of the miRNAs sequenced in the test results contribute to the treatment of subsequent reproductive diseases and the regulation of ovulation cycles.The results were as follows:(1)Through high-throughput sequencing,we found there were 11727490 raw sequences in the ovaries of Anhuai goats in follicular(Fols)phase,and 12209928 raw sequences in the ovaries of Anhuai goats in luteal(Luts)phase(LO).After removing the adaptor,11546193 pure sequences in the follicular phase library,and 12013471 pure sequences in the luteal phase library.(2)To acquire the lncRNA expression profile and genomic information,we then analyzed the miRNA transcriptome characteristics by bioinformatics.Firstly,comparing with the reference goat genome,slight mismatches between sequences were considered,339 and 353 known miRNAs were identified in the Fols and Luts,and the expression levels of 8482909 and 7136846 were obtained,respectively.The un-annotated sequences were mapped to the hircine genome to predict potential novel miRNA candidates,and 70 and 94 novel miRNAs were identified in the Fols and Luts libraries,and the expression levels of 182432 and 157756 were obtained,respectively,in which 25 novel miRNAs were co-expressed.(3)Differential expression,GO and KEGG analysis between FO and LO.There were 125 known miRNAs were extremely and significantly different between the two libraries,40 were up-regulation,85 were down-regulation.There were 51 novel miRNAs were extremely and significantly different between the two libraries,14 were up-regulation,37 were down-regulation.There were 22 novel miRNA specific expressed and significantly different.The results showed that there weren’t the pathways of miRNAs were significantly enriched(Q-value < 0.05),but the pathways of VEGF signaling pathway,Neuroactive ligand-receptor interaction and GnRH signaling pathway could be related to follicular development and corpus luteum In the new miRNA,the difference genes between FO and LO were enriched with 310 signaling pathways,which were enriched in amino acid metabolism,GnRH signal pathway and fat digestion and absorption pathway.(4)We then choosed 5 miRNA transcripts to verify the sequencing datas.The results showed that the expression levels which detected through real time PCR were basically consistent with the sequencing analysis.In conclusion,the study was the first to reveal miRNA expression profiles in the ovaries of goats by progressive high-throughput sequencing;finally,we not only predicted some novel miRNAs,but also some miRNA closely related to ovulation cycle in goat.We found 125 known miRNA and 51 kinds of novel lncRNA were significantly different between the two libraries.The let-7f,miR-21,mi-R145 and miR-125 a and VEGF signaling pathway,Neuroactive ligand-receptor interaction and GnRH signaling pathway may be related to ovulation cycle in goat.