title: A Niche for GFRα1-Positive Spermatogonia in the Terminal Segments of the Seminiferous Tubules in Hamster Testes.
abstract: In invertebrate species such as flies and nematodes, germline stem cells are maintained in a niche environment, which is restricted to the terminal end of the tubular structure in the gonads. In mice, spermatogonial stem cells (SSCs), a subpopulation of Asingle GFRα1 (glial cell line-derived neurotrophic factor [GDNF] family receptor-α1)-positive spermatogonia, are widely distributed along the longitudinal axis in the convoluted seminiferous tubules, preferentially juxtaposed to the interstitial vasculature. However, whether this area is the only SSC niche is not known. In this study, we identified a valve-like terminal segment of the seminiferous tubules, the Sertoli valve (SV), adjacent to the rete testis as another niche for GFRα1-positive spermatogonia in hamsters. Here, we show that the SV epithelium is composed of the modified Sertoli cells that are still capable of proliferation and missing most spermatogenic activities in the adult stage. The SV epithelium constitutively expresses GDNF, a major niche factor for SSCs, and supports the stable proliferation and selective maintenance of an Asingle subpopulation of GFRα1-positive spermatogonia in hamsters. The SV region of hamster seminiferous tubules has features that are similar to the stem cell niche in invertebrate gonads. Therefore, we propose that the SV may be a novel niche for Asingle GFRá1-positive spermatogonia potentially including a SSC population, at the terminal segments of the seminiferous tubules in hamsters.
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan.
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Aiyama
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Tsunekawa
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan.
authors.forename: Kasane
authors.initials: K
authors.lastname: Kishi
authors.affiliation: Department of Experimental Animal Model for Human Disease, Center for Experimental Animals, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, Tokyo, Japan.
authors.forename: Miyuri
authors.initials: M
authors.lastname: Kawasumi
authors.affiliation: Department of Experimental Animal Model for Human Disease, Center for Experimental Animals, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, Tokyo, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of Experimental Animal Model for Human Disease, Center for Experimental Animals, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, Tokyo, Japan.
authors.forename: Masami
authors.initials: M
authors.lastname: Kanai-Azuma
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Kurohmaru
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan.
authors.forename: Yoshiakira
authors.initials: Y
authors.lastname: Kanai
mesh_terms: D000818:Animals; D006224:Cricetinae; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors / Q000032:analysis*; D008297:Male; D008647:Mesocricetus; D008813:Mice, Inbred ICR; D012671:Seminiferous Tubules / Q000737:chemistry* / Q000166:cytology* / Q000502:physiology; D013093:Spermatogonia / Q000737:chemistry* / Q000502:physiology; D055153:Stem Cell Niche / Q000502:physiology; D013737:Testis / Q000737:chemistry / Q000166:cytology / Q000502:physiology
chemical_list: C494988:Gfra1 protein, mouse; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors
keywords: Glial cell line-derived neurotrophic factor; Glial cell line-derived neurotrophic factor family receptor-α1; Niche; Sertoli valve; Spermatogonial stem cell