Chromatin and single-cell RNA-seq profiling reveal dynamic signaling and metabolic transitions during human spermatogonial stem cell development

Journal article

Human adult spermatogonial stem cells (hSSCs) must balance self-renewal and differentiation. To understand how this is achieved, we profiled DNA methylation and open chromatin (ATAC-seq) in SSEA4+ hSSCs, analyzed bulk and single-cell RNA transcriptomes (RNA-seq) in SSEA4+ hSSCs and differentiating c-KIT+ spermatogonia, and performed validation studies via immunofluorescence. First, DNA hypomethylation at embryonic developmental genes supports their epigenetic "poising" in hSSCs for future/embryonic expression, while core pluripotency genes (OCT4 and NANOG) were transcriptionally and epigenetically repressed. Interestingly, open chromatin in hSSCs was strikingly enriched in binding sites for pioneer factors (NFYA/B, DMRT1, and hormone receptors). Remarkably, single-cell RNA-seq clustering analysis identified four cellular/developmental states during hSSC differentiation, involving major transitions in cell-cycle and transcriptional regulators, splicing and signaling factors, and glucose/mitochondria regulators. Overall, our results outline the dynamic chromatin/transcription landscape operating in hSSCs and identify crucial molecular pathways that accompany the transition from quiescence to proliferation and differentiation.

Authors: Guo, J; Grow, E; Yi, C; Mlcochova, H; Maher, G

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: Cell Stem Cell
• Volume: 21
• Issue: 4
• Pages: 533-546.e6
• Publication date: 2017-10-05
• Acceptance date: 2017-09-01
• DOI: 10.1016/j.stem.2017.09.003
• EISSN: 1875-9777
• ISSN: 1934-5909
• Pmid: 28985528
• Language: English
• Keywords: spermatogenesis; DNA methylation; pluripotency; human spermatogonial stem cells; hormone receptors; metabolism; single-cell RNA-seq; open chromatin