Transcriptome And Genome-wide DNA Methylation Association Analysis Of Prepubertal And Pubertal Goats’ Pineal Gland

Endocrine of the hypothalamic-pituitary-ovary axis plays a key role during the initiation of puberty,and it is tightly regulated by pineal gland.In this study,transcriptome sequencing was performed on the prepubertal and pubertal female Anhui white goats’ pineal glands.Then GO(Gene Ontology)enrichment analysis and KEGG(Kyoto Encyclopedia of Genes and Genomes)signaling pathway analysis were performed.Combined with whole-genome methylation analysis,the aim was to screen candidate genes related to puberty initiation of goat and regulated by DNA methylation,so as to lay a foundation for elucidating the mechanism of puberty initiation and improve reproductive performance of goats.The research results are as follows:(1)Compared with the transcriptome of the prepubertal goats’ pineal gland,1,400 genes were significantly up-regulated and 1,303 genes were significantly down-regulated in the prepubertal goats’ pineal gland.Among them,the fold change of LIN28 B,GIP,OPN1 SW and DCC were especially significant.By analyzing the overlapping genes of transcriptome and genome-wide methylation,it was found that methylation of both gene promoter region and gene body region had significant effects on transcriptome.A total of 60 negatively correlated genes and 67 positively correlated genes were found.(2)By GO enrichment analysis of transcriptome sequencing,multiple enrichment items related to the biological functions of mitochondria and ribosomes were found,mainly including GO items such as mitochondrial respiratory chain complex assembly,NADH dehydrogenase complex assembly,mitochondrial protein complex and structural constituent of ribosome.The KEGG analysis showed that the differentially expressed genes were mainly enriched in metabolic pathways,oxidative phosphorylation,thermogenesis,ribosome and Parkinson’s disease and other pathways related to neurological diseases.A number of key genes enriched in multiple pathways,such as ATP5F1 D,UQCRC1 and PIK3C3,were screened out.(3)The GO analysis was performed on the overlapping genes of transcriptome and genome-wide methylation were mainly enriched in negative regulation of neuron projection regeneration,regulation of neuron differentiation and phosphatidylinositol-related items.The KEGG analysis showed that overlapping genes were mainly enriched in metabolic pathways,oxidative phosphorylation,Parkinson’s disease and other pathways related to neurological diseases.A group of the differentially expressed genes regulated by DNA methylation significantly,such as ATP5F1 D,CACNB2 and PTEN,were screened out.Conclusion: Compared with prepubertal goats,the transcriptome of the pineal gland of Anhui white goats changed significantly in puberty and the difference multiples of LIN28 B,GIP,OPN1 SW and DCC were the most significant,but only the methylation profiles of some different expression genes changed significantly,such as ATP5F1 D,CACNB2 and PTEN.