Loss of Sertoli-Germ Cell Adhesion Determines the Rapid Germ Cell Elimination During the Seasonal Regression of the Seminiferous Epithelium of the Long Hairy Armadillo Chaetophract...

Authors
Luaces, Juan Pablo; Rossi, Luis Francisco; Sciurano, Roberta Beatriz; Rebuzzini, Paola; Merico, Valeria; Zuccotti, Maurizio; Merani, Maria Susana; Garagna, Silvia
Publication Year
2014
Language
English
Format
article
Status
Published version
Description
The armadillo Chaetophractus villosus is a seasonal breeder whose seminiferous epithelium undergoes rapid regression with massive germ cell loss, leaving the tubules with only Sertoli cells and spermatogonia. Here, we addressed the question of whether this regression entails 1) the disassembly of cell junctions (immunolocalization of nectin-3, Cadm1, N-cadherin, and beta-catenin, and transmission electron microscopy [TEM]); 2) apoptosis (immunolocalization of cytochrome c and caspase 3; TUNEL assay); and 3) the involvement of Sertoli cells in germ cell phagocytosis (TEM). We showed a dramatic reduction in the extension of vimentin filaments associated with desmosomelike junctions at the interface between Sertoli and germ cells, and an increased diffusion of the immunosignals of nectin-3, Cadm1, N-cadherin, and beta-catenin. Together, these results suggest loss of Sertoli-germ cell adhesion, which in turn might determine postmeiotic cell sloughing at the beginning of epithelium regression. Then, loss of Sertoli-germ cell adhesion triggers cell death. Cytochrome c is released from mitochondria, but although postmeiotic cells were negative for late apoptotic markers, at advanced regression spermatocytes were positive for all apoptotic markers. Transmission electron microscopy analysis showed cytoplasmic engulfment of cell debris and lipid droplets within Sertoli cells, a sign of their phagocytic activity, which contributes to the elimination of the residual meiocytes still present in the latest regression phases. These findings are novel and add new players to the mechanisms of seminiferous epithelium regression occurring in seasonal breeders, and they introduce the armadillo as an interesting model for studying seasonal spermatogenesis.
Fil: Luaces, Juan Pablo. Universidad de Buenos Aires. Facultad de Medicina. Laboratorio de Biología Cromosómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Rossi, Luis Francisco. Universidad de Buenos Aires. Facultad de Medicina. Laboratorio de Biología Cromosómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Sciurano, Roberta Beatriz. Universidad de Buenos Aires. Facultad de Medicina. Laboratorio de Biología Cromosómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Rebuzzini, Paola. Università degli Studi di Pavia; Italia
Fil: Merico, Valeria. Università degli Studi di Pavia; Italia
Fil: Zuccotti, Maurizio. Università di Parma; Italia
Fil: Merani, Maria Susana. Universidad de Buenos Aires. Facultad de Medicina. Laboratorio de Biología Cromosómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Garagna, Silvia. Università degli Studi di Pavia; Italia
Subject
Adhesion molecules
Anoikis
Apoptosis
Cadm1
Intermediate filaments
N-cadherin
β-catenin
Nectin-3
Phagocytosis
Seasonal reproduction
Spermatogenesis
Testosterone
Biología Reproductiva
Ciencias Biológicas
CIENCIAS NATURALES Y EXACTAS
Biología del Desarrollo
Ciencias Biológicas
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/16985