Sertoli cell vacuolization and abnormal germ cell adhesion in mice deficient in an inositol polyphosphate 5-phosphatase.
The dynamic nature of cellular interactions during differentiation of germ cells and their translocation from the basement membrane to the lumen of the seminiferous tubules requires the existence of complex and well-regulated cellular adhesion mechanisms in the testis. Successful migration of the developing germ cells is characterized by dynamic breakage and reformation of cadherin-containing adherens junctions between the germ cells and Sertoli cells, the polarized somatic cells of the testis that support and nourish the developing gametes. Here, we demonstrate the accumulation of abnormally swollen, actin-coated, endosome-like structures that contain intact adherens junctions and stain positive for N-cadherin and beta-catenin in the Sertoli cell cytosol of mice deficient in Inpp5b, an inositol polyphosphate 5-phosphatase. Simultaneous to the formation of these abnormal structures, developing germ cells are prematurely released from the seminiferous epithelium and sloughed into the epididymis. Our results demonstrate a role for Inpp5b in the regulation of cell adhesion in the testis and in the formation of junctional complexes with neighboring cells, and they emphasize the important and essential role of phosphoinositides in spermatogenesis.
Hellsten
Elina
E
Genetic Diseases Research Branch, National Human Genome Research Institute, Veterinary Resources Program, Office of Director, National Institutes of Health, 49 Convent Drive, Bethesda, MD 20892, USA.
Bernard
David J
DJ
Owens
Jennie W
JW
Eckhaus
Michael
M
Suchy
Sharon F
SF
Nussbaum
Robert L
RL
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D015820:Cadherins / Q000096:biosynthesis; D002448:Cell Adhesion / Q000235:genetics; D002462:Cell Membrane / Q000502:physiology; D003598:Cytoskeletal Proteins / Q000378:metabolism; D004705:Endocytosis / Q000502:physiology; D004847:Epithelial Cells / Q000502:physiology; D005260:Female; D005298:Fertility / Q000235:genetics; D005854:Germ Cells / Q000502:physiology* / Q000648:ultrastructure; D007150:Immunohistochemistry; D000072181:Inositol Polyphosphate 5-Phosphatases; D007365:Intercellular Junctions / Q000502:physiology / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008854:Microscopy, Electron; D010641:Phenotype; D010744:Phosphoric Monoester Hydrolases / Q000172:deficiency* / Q000235:genetics; D012708:Sertoli Cells / Q000648:ultrastructure*; D013737:Testis / Q000648:ultrastructure; D015534:Trans-Activators / Q000378:metabolism; D014617:Vacuoles / Q000648:ultrastructure*; D051176:beta Catenin
C495267:CTNNB1 protein, mouse; D015820:Cadherins; D003598:Cytoskeletal Proteins; D015534:Trans-Activators; D051176:beta Catenin; D010744:Phosphoric Monoester Hydrolases; D000072181:Inositol Polyphosphate 5-Phosphatases