Screening And Identification Of Long Noncoding RNAs In The Pubertal Female Goats

Puberty is a pivotal stage in female animal development,and marks the onset of reproductive capability.Recently,epigenetic mechanisms of transcriptional regulation have been found to play a crucial role in the onset of puberty in female animals.Long noncoding RNA?lncRNA?are a key players in epigenetics,and have been shown to participate in reproductive stages.However,little is known about the function of lncRNA in goat puberty.In this study,we applied RNA-seq to investigate the expression profiles of lncRNA in female goats,then we explored the function of lncRNA and enriched pathways associated with puberty.The time of pubertal female goats in the study was determined by male goats detecting estrus and the appearance changes of vulva and ovary.Firstly,differential expressed lncRNA of the pubertal?4.5M⁵M;16.17±0.50kg?and prepubertal?2.5M³M;8.30±0.61kg?hypothalamus was screened out by using RNA-seq technology.Then,prediction of target genes of lncRNA and pathway analysis were also performed.Sequencing results were validated using qRT-PCR analysis and candidated lncRNA was screened.Hypothalamus nerve cells were separated and cultured from new borth female rats.The function of candidate lncRNA was verified by siRNA interference in hypothalamus nerve cell.The results of interference were validated by qRT-PCR analysis.Our results showed 2943 predicted lncRNAs,including 2012 differentially expressed lncRNAs,which corresponded to 5412 target genes.We also investigated the role of lncRNAs that the target genes of lncRNAs involved in the regulation of puberty.Kyoto Encyclopedia of Genes and Genomes?KEGG?or gene ontology?GO?analyses showed several pathways were enriched,such as oxytocin signaling pathway,sterol biosynthetic process,and pheromone receptor activity signaling pathway.We interfered the expression of lncRNA XLOC₄46331 by specific siRNA in vitro,the results showed that the expression of lncRNA XLOC₄46331 and target genes Igfbp5 decreased in nerve cell?P<0.01?,moreover Igf-1,the genes involved in puberty,also decreased?P<0.05?.In conclusion,Our results primarily demonstrate the differential expressed lncRNA in hypothalamus of pubertal female goats.These lncRNAs and enriched pathways of their target genes may play important roles in regulating puberty in goats.The candidate lncRNA XLOC₄46331 is likely to participate in the regulation of puberty via target Igfbp5.These results may provide a new reference for mechanical studies of puberty.