Single-cell transcriptome analysis of the germ cells and somatic cells during mitotic quiescence stage in goats.

The mitotic quiescence of prospermatogonia is the event known to occur during genesis of the male germline and is tied to the development of the spermatogenic lineage. The regulatory mechanisms and the functional importance of this process have been demonstrated in mice; however, regulation of this process in human and domestic animal is still largely unknown. In this study, we employed single-cell RNA sequencing to identify transcriptional signatures of prospermatogonia and major somatic cell types in testes of goats at E85, E105, and E125. We identified both common and specific Gene Ontology categories, transcription factor regulatory networks, and cell-cell interactions in cell types from goat testis. We also analyzed the transcriptional dynamic changes in prospermatogonia, Sertoli cells, Leydig cells, and interstitial cells. Our datasets provide a useful resource for the study of domestic animal germline development.

Developmental Mapping of Hair Follicles in the Embryonic Stages of Cashmere Goats Using Proteomic and Metabolomic Construction.

The hair follicle (HF) is the fundamental unit for fleece and cashmere production in cashmere goats and is crucial in determining cashmere yield and quality. The mechanisms regulating HF development in cashmere goats during the embryonic period remain unclear. Growing evidence suggests that HF development involves complex developmental stages and critical events, and identifying the underlying factors can improve our understanding of HF development. In this study, samples were collected from embryonic day 75 (E75) to E125, the major HF developmental stages. The embryonic HFs of cashmere goats were subjected to proteomic and metabolomic analyses, which revealed dynamic changes in the key factors and signalling pathways controlling HF development at the protein and metabolic levels. Gene ontology and the Kyoto Encyclopaedia of Genes and Genomes were used to functionally annotate 1784 significantly differentially expressed proteins and 454 significantly differentially expressed metabolites enriched in different HF developmental stages. A joint analysis revealed that the oxytocin signalling pathway plays a sustained role in embryonic HF development by activating the MAPK and Ca2+ signalling pathways, and a related regulatory network map was constructed. This study provides a global perspective on the mechanism of HF development in cashmere goats and enriches our understanding of embryonic HF development.

Effect of Fibroblast Growth Factor 10 and an Interacting Non-Coding RNA on Secondary Hair Follicle Dermal Papilla Cells in Cashmere Goats' Follicle Development Assessed by Whole-Transcriptome Sequencing Technology.

Cashmere, a keratinised product of secondary hair follicles (SHFs) in cashmere goats, holds an important place in international high-end textiles. However, research on the complex molecular and signal regulation during the development and growth of hair follicles (HFs), which is essential for the development of the cashmere industry, is limited. Moreover, increasing evidence indicates that non-coding RNAs (ncRNAs) participate in HF development. Herein, we systematically investigated a competing endogenous RNA (ceRNA) regulatory network mediated by circular RNAs (circRNAs), microRNAs (miRNAs), and messenger RNAs (mRNAs) in skin samples of cashmere goat embryos, using whole-transcriptome sequencing technology. We obtained 6468, 394, and 239 significantly differentially expressed mRNAs, circRNAs, and miRNAs, respectively. These identified RNAs were further used to construct a ceRNA regulatory network, mediated by circRNAs, for cashmere goats at a late stage of HF development. Among the molecular species identified, miR-184 and fibroblast growth factor (FGF) 10 exhibited competitive targeted interactions. In secondary HF dermal papilla cells (SHF-DPCs), miR-184 promotes proliferation, inhibits apoptosis, and alters the cell cycle via the competitive release of FGF10. This study reports that FGF10 and its interaction with ncRNAs significantly affect SHF-DPCs, providing a reference for research on the biology of HFs in cashmere goats and other mammals.

Integration of single-cell transcriptome and chromatin accessibility of early gonads development among goats, pigs, macaques, and humans.

The early gonads of mammals contain primordial germ cells (PGCs) and somatic cell precursors that are essential for sex determination and gametogenesis. Although it is extensively documented in mice, the development of early gonads in non-rodents remains to be delineated. Because molecular differences between mouse and human gonadal cells have been reported, it warrants the study of the key markers and regulatory features that are conserved or divergent between non-rodent species and human. Here, we integrate single-cell transcriptome and chromatin accessibility analysis to identify regulatory signatures of PGCs and somatic cells in the early gonads of goats, pigs, macaques, and humans. We identify the evolutionarily conserved and species-specific events, including genes expression, signaling pathways, and cell-cell interactions. We also uncover potential cis-regulatory elements and key transcription factors in PGCs and somatic cells. Our datasets provide important resources for better understanding the evolutionary programs of PGCs and gonadal somatic cell development in mammals.