Identification of Circular RNAs in Hypothalamus of Gilts during the Onset of Puberty.

Qingnan Li,Nian Li,Yaosheng Chen,Xiaolong Yuan,Xiangchun Pan,Wentao Gong

doi:10.3390/genes12010084

Abstract

The disorders of puberty have shown negative outcomes on health of mammals, and the hypothalamus is thought to be the main regulator of puberty by releasing GnRH. Many studies show that the circular RNAs (circRNAs) might be implicated in the timing of puberty in mammals. However, the circRNAs in the hypothalamus of gilts have not been explored. To profile the changes and biological functions of circRNAs in the hypothalamus during the onset of puberty, RNA-seq was utilized to establish pre-, in-, and post-pubertal hypothalamic circRNAs profiles. In this study, the functions of hypothalamic circRNAs were enriched in the signaling pathway of neurotrophin, progesterone-mediated oocyte maturation, oocyte meiosis, insulin, ErbB, and mTOR, which have been highly suggested to be involved in the timing of puberty. Furthermore, 53 circRNAs were identified to be putative hypothalamus-specific expressed circRNAs, and some of them were exclusively expressed in the one of three pubertal stages. Moreover, 22 differentially expressed circRNAs were identified and chosen to construct the circRNA-miRNA-gene network. Moreover, 10 circRNAs were found to be driven by six puberty-related genes (ESR1, NF1, APP, ENPP2, ARNT, and DICER1). Subsequently, the expression changes of several circRNAs were confirmed by RT-qPCR. Collectively, the preliminary results of hypothalamic circRNAs provided useful information for the investigation of the molecular mechanism for the timing of puberty in gilts.

Highlights

IntroductionPuberty is widely defined as the emergence of the first estrous and capable of reproduction [1]
In female pigs, puberty is widely defined as the emergence of the first estrous and capable of reproduction [1]
The release of gonadotropin-releasing hormone (GnRH) from the hypothalamus leads to the release of FSH and LH from the pituitary [5], and the FSH and LH act on the folliculogenesis, oogenesis, and sex steroid of the gonads to arouse the timing of puberty in mammals [6]

Summary

Introduction

Puberty is widely defined as the emergence of the first estrous and capable of reproduction [1]. The onset of puberty is controlled and driven by hypothalamic-pituitary-gonadal (HPG) axis. The release of gonadotropin-releasing hormone (GnRH) from the hypothalamus leads to the release of FSH and LH from the pituitary [5], and the FSH and LH act on the folliculogenesis, oogenesis, and sex steroid of the gonads to arouse the timing of puberty in mammals [6]. E.C. et al demonstrated that the deletion of homeodomain protein sine oculis-related homeobox 6 (Six6) in hypothalamic GnRH neuron can leads to infertility [8]. These demonstrations indicate that the hypothalamus plays an essential role in the onset of puberty

Methods

Results

Discussion

Conclusion