Spermatogenesis is a stem cell-driven process by which a single spermatogonial stem cell (SSC) differentiates into many haploid spermatozoa. SSC division either follows the asymmetric model, whereby a stem cell produces one differentiated cell and one stem cell (self-renewal), or the symmetric model, whereby a stem cell produces two differentiated cells or two stem cells. Regardless of the model, the process of self-renewal and differentiation are thought to be under control by numerous signals from the surrounding somatic tissue (the stem-cell niche) and germ stem cells themselves. Moreover, recent studies have shown that non-coding RNAs (microRNAs, cirRNAs, lncRNAs) can exert a role in reproduction, in particular regulating sex determination, sex differentiation and gametogenesis. Among the non-coding RNAs, lncRNAs have been shown to regulate the transcription of regulatory "master" genes involved in several biological processes, including stem cell differentiation and maintenance of stem-cell pluripotency.
We invite researches to contribute with original research and review articles that provide new insights on the mechanisms that regulate the different modes of male germ stem cell division (asymmetrical versus symmetrical) in invertebrates and vertebrates. In particular, we encourage studies that cover the interaction between endocrine systems and local testicular signals, such as sexual steroids, growth factors and non-coding RNAs in control of male germline stem cells under normal or altered physiological conditions (pathology, aging, or exposure to environmental contaminants). The most recent methods of investigation (testicular organoids, single cell RNA seq, CRISPR/Cas9, germ cell transplantation) in combination with traditional experimental model species (C. elegans, Drosophila, zebrafish, medaka, Xenopus, mice and rats among others) or cell lines are welcome in this Research Topic. Finally, review articles covering the evolutionary aspects of the endocrine and paracrine regulation of male germline stem cells across the animal kingdom highlighting the conserved mechanisms and their peculiarities are also invited.
Potential topics include, but are not limited to:
• The process of male germline stem cell division (asymmetrical or symmetrical)
• Interactions between spermatogonial stem cells and somatic cells
• Maintenance of spermatogonial stem cells in the niche and possible homing mechanisms
• Endocrine and paracrine regulation of spermatogonial stem cells
• Spermatogonial stem cell self-renewal and pro-differentiating growth factors
• Germ cell-derived growth factors
• Gonadotropin regulation in the spermatogonial stem cell niche
• Epigenetic control of male germline stem cells
• Non-coding RNAs involved in the male germline stem cell survival, self-renewal and differentiation process
• Sexual steroid hormones regulating germline stem cell division
• Germ stem cell cultures (including cell feeder, organotypic, and Testicular organoids) as tools to study spermatogonial stem cells
Spermatogenesis is a stem cell-driven process by which a single spermatogonial stem cell (SSC) differentiates into many haploid spermatozoa. SSC division either follows the asymmetric model, whereby a stem cell produces one differentiated cell and one stem cell (self-renewal), or the symmetric model, whereby a stem cell produces two differentiated cells or two stem cells. Regardless of the model, the process of self-renewal and differentiation are thought to be under control by numerous signals from the surrounding somatic tissue (the stem-cell niche) and germ stem cells themselves. Moreover, recent studies have shown that non-coding RNAs (microRNAs, cirRNAs, lncRNAs) can exert a role in reproduction, in particular regulating sex determination, sex differentiation and gametogenesis. Among the non-coding RNAs, lncRNAs have been shown to regulate the transcription of regulatory "master" genes involved in several biological processes, including stem cell differentiation and maintenance of stem-cell pluripotency.
We invite researches to contribute with original research and review articles that provide new insights on the mechanisms that regulate the different modes of male germ stem cell division (asymmetrical versus symmetrical) in invertebrates and vertebrates. In particular, we encourage studies that cover the interaction between endocrine systems and local testicular signals, such as sexual steroids, growth factors and non-coding RNAs in control of male germline stem cells under normal or altered physiological conditions (pathology, aging, or exposure to environmental contaminants). The most recent methods of investigation (testicular organoids, single cell RNA seq, CRISPR/Cas9, germ cell transplantation) in combination with traditional experimental model species (C. elegans, Drosophila, zebrafish, medaka, Xenopus, mice and rats among others) or cell lines are welcome in this Research Topic. Finally, review articles covering the evolutionary aspects of the endocrine and paracrine regulation of male germline stem cells across the animal kingdom highlighting the conserved mechanisms and their peculiarities are also invited.
Potential topics include, but are not limited to:
• The process of male germline stem cell division (asymmetrical or symmetrical)
• Interactions between spermatogonial stem cells and somatic cells
• Maintenance of spermatogonial stem cells in the niche and possible homing mechanisms
• Endocrine and paracrine regulation of spermatogonial stem cells
• Spermatogonial stem cell self-renewal and pro-differentiating growth factors
• Germ cell-derived growth factors
• Gonadotropin regulation in the spermatogonial stem cell niche
• Epigenetic control of male germline stem cells
• Non-coding RNAs involved in the male germline stem cell survival, self-renewal and differentiation process
• Sexual steroid hormones regulating germline stem cell division
• Germ stem cell cultures (including cell feeder, organotypic, and Testicular organoids) as tools to study spermatogonial stem cells
