Developmental and molecular aberrations associated with deterioration of oogenesis during complete or partial follicle-stimulating hormone receptor deficiency in mice.
Targeted disruption of the mouse FSH receptor gene (FSH-R) that mediates the action of the FSH results in a gene dose-related ovarian phenotype in the developing as well as the adult animal. While null females (FORKO) are sterile, the haplo-insufficient mice experience early reproductive senescence. The purpose of this study was to first record changes in oocyte development in the null FORKO and haplo-insufficient mice. Oocyte growth is significantly retarded in the null mutants with thinner zona pellucida in preantral follicles, but thicker zona pellucida in secondary follicles. This morphometric change indicates developmental aberrations in coordination of the germ cell (oocyte) and the somatic granulosa cell (GC) compartments. Markers for primordial germ cell proliferation and oocyte growth, such as the c-Kit/Kit-ligand and bone morphogenetic protein-15 (BMP-15) were downregulated in both null and +/- ovaries, suggesting disrupted communication between oocyte and GCs. Extensive changes in the expression of other oocyte-specific gene products like the zona pellucida glycoproteins (zona pellucida A, B, and C) indicate major alteration in the extracellular matrix surrounding the germ cells. This led to leaky germ cells that allowed infiltration of somatic cells. These results show that the loss of FSH-R signaling alters the follicular environment, where oocyte-granulosa interactions are perturbed, creating an out-of-phase germ cell and somatic cell development. We believe that these data provide an experimental paradigm to explore the mechanisms responsible for preserving the structural integrity and quality of oocytes at different ages.
Yang
Yinzhi
Y
Molecular Reproduction Research Laboratory, Clinical Research Institute of Montreal, Montreal, Quebec, Canada H2W 1R7.
Balla
Agneta
A
Danilovich
Natalia
N
Sairam
M Ram
MR
D000818:Animals; D015415:Biomarkers; D055430:Bone Morphogenetic Protein 15; D002450:Cell Communication; D004527:Egg Proteins / Q000378:metabolism; D005109:Extracellular Matrix / Q000502:physiology / Q000648:ultrastructure; D005260:Female; D055429:Growth Differentiation Factor 9; D006579:Heterozygote; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D008817:Mice, Mutant Strains; D009865:Oocytes / Q000166:cytology* / Q000502:physiology*; D009866:Oogenesis / Q000235:genetics*; D006080:Ovarian Follicle / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D011956:Receptors, Cell Surface; D011962:Receptors, FSH / Q000172:deficiency* / Q000235:genetics; D019089:Stem Cell Factor / Q000378:metabolism; D015044:Zona Pellucida / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D000072216:Zona Pellucida Glycoproteins
D015415:Biomarkers; C525902:Bmp15 protein, mouse; D055430:Bone Morphogenetic Protein 15; D004527:Egg Proteins; C525898:Gdf9 protein, mouse; D055429:Growth Differentiation Factor 9; D036341:Intercellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D011962:Receptors, FSH; D019089:Stem Cell Factor; D000072216:Zona Pellucida Glycoproteins; D019009:Proto-Oncogene Proteins c-kit