title: Germ cell-specific sustained activation of Wnt signalling perturbs spermatogenesis in aged mice, possibly through non-coding RNAs.
abstract: Dysregulated Wnt signalling is associated with human infertility and testicular cancer. However, the role of Wnt signalling in male germ cells remains poorly understood. In this study, we first confirmed the activity of Wnt signalling in mouse, dog and human testes. To determine the physiological importance of the Wnt pathway, we developed a mouse model with germ cell-specific constitutive activation of βcatenin. In young mutants, similar to controls, germ cell development was normal. However, with age, mutant testes showed defective spermatogenesis, progressive germ cell loss, and flawed meiotic entry of spermatogonial cells. Flow sorting confirmed reduced germ cell populations at the leptotene/zygotene stages of meiosis in mutant group. Using thymidine analogues-based DNA double labelling technique, we further established decline in germ cell proliferation and differentiation. Overactivation of Wnt/βcatenin signalling in a spermatogonial cell line resulted in reduced cell proliferation, viability and colony formation. RNA sequencing analysis of testes revealed significant alterations in the non-coding regions of mutant mouse genome. One of the novel non-coding RNAs was switched on in mutant testes compared to controls. QPCR analysis confirmed upregulation of this unique non-coding RNA in mutant testis. In summary, our results highlight the significance of Wnt signalling in male germ cells.
authors.affiliation: School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: Manish
authors.initials: M
authors.lastname: Kumar
authors.affiliation: School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: Joshua
authors.initials: J
authors.lastname: Atkins
authors.affiliation: School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: Murray
authors.initials: M
authors.lastname: Cairns
authors.affiliation: School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: Ayesha
authors.initials: A
authors.lastname: Ali
authors.affiliation: School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: Pradeep S
authors.initials: PS
authors.lastname: Tanwar
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D049109:Cell Proliferation; D002478:Cells, Cultured; D004285:Dogs; D006801:Humans; D008297:Male; D008540:Meiosis; D051379:Mice; D008810:Mice, Inbred C57BL; D022661:RNA, Untranslated / Q000502:physiology*; D013091:Spermatogenesis / Q000502:physiology*; D013094:Spermatozoa / Q000502:physiology; D060449:Wnt Signaling Pathway / Q000502:physiology*
chemical_list: D022661:RNA, Untranslated
keywords: Gerotarget; Wnt; fertility; spermatgonia; testicular cancer; βcatenin