Abstract
Germline stem cells (GSCs) are adult stem cells that are responsible for the production of gametes and include spermatogonial stem cells (SSCs) and ovarian germline stem cells (OGSCs). GSCs are located in a specialized microenvironment in the gonads called the niche. Many recent studies have demonstrated that multiple signals in the niche jointly regulate the proliferation and differentiation of GSCs, which is of significance for reproductive function. Previous studies have demonstrated that the hedgehog (Hh) signaling pathway participates in the proliferation and differentiation of various stem cells, including GSCs in Drosophila and male mammals. Furthermore, the discovery of mammalian OGSCs challenged the traditional opinion that the number of primary follicles is fixed in postnatal mammals, which is of significance for the reproductive ability of female mammals and the treatment of diseases related to germ cells. Meanwhile, it still remains to be determined whether the Hh signaling pathway participates in the regulation of the behavior of OGSCs. Herein, we review the current research on the role of the Hh signaling pathway in mediating the behavior of GSCs. In addition, some suggestions for future research are proposed.
Highlights
Stem cells have many possible applications based on their ability for differentiation
In 1980, when Nusslein-Volhard and Wieschaus were screening genes that affected the growth of fly larvae, they found that a certain mutated gene caused hedgehog-like spiked protrusions on the ventral side of Drosophila embryos; the gene was named Hh [3]
They are located in a niche that is mainly composed of spermatogonial stem cells (SSCs), Sertoli cells (SCs), Leydig cells (LCs), peritubular myoid (PTM) cells, and other spermatogonia and spermatic cells in various differentiation phases
Summary
Stem cells have many possible applications based on their ability for differentiation. GSCs are adult stem cells responsible for the production of gametes. The proper maintenance of GSCs is regulated by various signals in the surrounding microenvironment (the niche). The hedgehog (Hh) signaling pathway was identified as a relevant regulator of GSCs through its direct regulation of GSCs and indirect regulation of the niche surrounding GSCs to affect GSCs. In recent years, the hedgehog (Hh) signaling pathway was identified as a relevant regulator of GSCs through its direct regulation of GSCs and indirect regulation of the niche surrounding GSCs to affect GSCs Because of their ability for differentiation, GSCs have possible applications in reproductive medicine. We review and, respectively, discuss the effect of the Hh signaling pathway on the proliferation and differentiation of SSCs in Drosophila and male mammals, the migration of OGSCs from the ovarian surface epithelium (OSE) to the ovary cortex, and the development of OGSCs in the ovary cortex of mammals
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
