The Mammalian Spermatogenesis Single-Cell Transcriptome, from Spermatogonial Stem Cells to Spermatids

Spermatogenesis is a complex and dynamic cellular differentiation process critical to male reproduc- tion and sustained by spermatogonial stem cells (SSCs). Although patterns of gene expression have been described for aggregates of certain spermato- genic cell types, the full continuum of gene expres- sion patterns underlying ongoing spermatogenesis in steady state was previously unclear. Here, we cat- alog single-cell transcriptomes for >62,000 individual spermatogenic cells from immature (postnatal day 6) and adult male mice and adult men. This allowed us to resolve SSC and progenitor spermatogonia, eluci- date the full range of gene expression changes dur- ing male meiosis and spermiogenesis, and derive unique gene expression signatures for multiple mouse and human spermatogenic cell types and/or subtypes. These transcriptome datasets provide an information-rich resource for studies of SSCs, male meiosis, testicular cancer, male infertility, or contra- ceptive development, as well as a gene expression roadmap to be emulated in efforts to achieve sper- matogenesis in vitro