Dynamic transcriptome and chromatin architecture in granulosa cells during chicken folliculogenesis
Ontology highlight
ABSTRACT: Ovarian follicle development is a complex and well-orchestrated biological process. Granulosa cells (GCs) are the most important somatic cells in the ovary, which play important roles in the growth of follicles. Three-dimensional (3D) chromatin architecture has emerged as an important regulator of transcription in eukaryote, but how these changes in granulosa cells during folliculogenesis of chicken are largely unexplored. Here, we performed an integrative analysis of transcriptomic and chromatin structural characterization for chicken follicular granulosa cells of 10 and 3 growth stages respectively.
Project description:The dynamic transcriptional regulation and interactions of human germlines and surrounding somatic cells during folliculogenesis remains unknown. Using RNA-Seq analysis of human oocytes and corresponding granulosa cells (GCs) spanning five follicular stages, we revealed unique features in transcriptional machinery, transcription factor networks and reciprocal interactions in human oocytes and GCs that displayed developmental-stage-specific expression patterns. Notably, we identified specific gene signatures of two cell types in particular developmental stage that may reflect developmental competency and ovarian reserve. Additionally, we uncovered key pathways that may concert germline-somatic interactions and drive the transition of primordial-to-primary follicle which represents follicle activation. Thus, our work provides key insights into the crucial features of the transcriptional regulation in the stepwise folliculogenesis and offers important clues for improving follicle recruitment in-vivo and restoring fully competent oocytes in-vitro.
Project description:Ovarian follicle development is a complex and well orchestrated biological process. Chromatin spatial organization has emerged as an important regulator of gene expression, but how these changes during follicle development are still unknown. Here, we integrated RNA-seq and Hi-C analyses of chicken follicular granulosa cells of 10 developmental stages. Our data revealed that SWF, F1, and POF had the greatest transcriptome differences from other stages. Our results provide a genome-wide atlas of chromatin interactions during chicken ovarian follicle development.
Project description:Obesity is known to affect female reproduction, as evidenced by obese patients suffering from subfertility and abnormal oogenesis. However, the underlying mechanisms by which obesity impairs folliculogenesis are poorly documented. Here, we performed comprehensive single-cell transcriptome analysis in both regular diet (RD) and obese mouse models to systematically uncover how obesity affects ovarian follicle cells and their interactions. We found an increased proportion of Inhbb highly expressed granulosa cells (GCs) among all the GC subpopulations in obese mice. Under obese conditions, excessive androgen secreted from endocrine theca cells (ETCs) may contribute to the imbalanced change of GC subtypes through ETCs-GCs interactions. This is alleviated by enzalutamide, an androgen receptor antagonist. We also identified and confirmed typical GC markers, such as Marcks and Prkar2b, for sensitive evaluation of female fertility in obesity. These data represent a resource for studying transcriptional networks and cell-cell interactions during folliculogenesis under physiological and pathological conditions.
Project description:Human granulosa cells (GCs), obtained during medical reproductive procedures can be cultured and are a cellular model for the human ovary. Oxygen concentrations are regarded as important regulators of GCs. We examined consequences of low (1%) O2 versus standard atmospheric conditions in cultured human GCs for four days. A proteomic analysis of three pools of human GCs was performed. While differences between the pools of GCs were noted, the abundance of 133 proteins was significantly increased in hypoxia in all samples, whereas the abundance of 391 proteins was decreased.
Project description:Human ovarian folliculogenesis is an highly regulated and complex process. Characterization of follicular cell signatures during this dynamic process is important to understand follicle fate (to grow, become dominant or undergo atresia). The transcriptional signature of human oocytes and granulosa cells (GC) in early-growing and ovulatory follicles have been previously described, however that of oocytes with surrounding GCs in small antral follicles have not been studied yet. Here, we have generated a unique dataset of single-cell transcriptomics (SmartSeq2) consisting of the oocyte with surrounding GCs from several individual (non-dominant) small antral follicles isolated from adult human ovaries. We have identified two main types of (healthy) follicles, with a distinct oocyte and GC signature. Using the CellphoneDB algorithm, we then investigated the bi-directional ligand-receptor interactions regarding the TGFβ/BMP, WNT, NOTCH, and receptor tyrosine kinases (RTK) signaling pathways between oocyte and GCs within each antral follicle type. Our work not only revealed the diversity of small antral follicles but also contributes to fill the gap in mapping the molecular landscape of human folliculogenesis and oogenesis.
Project description:Human granulosa cells are follicular cells surrounding the oocyte. Human granulosa cells are retrieved during in vitro fertilization a process where patients undergo hormonal stimulation including FSH and LH/hCG stimulation. Under the influence of the luteinizing hormone (LH) a process called luteinization they differentiate to luteal cells and contribute to the corpus luteum. Therefore, this cellular system is a good model for human corpus luteum (CL). To study processes within the human CL, IVF-derived GCs from patients were cultured for two to five days and then analyzed with mass spectrometry based shotgun proteomics.