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Mammalian Oocytes Locally Remodel Follicular Architecture to Provide the Foundation for Germline-Soma Communication

2018; Elsevier BV; Volume: 28; Issue: 7 Linguagem: Inglês

10.1016/j.cub.2018.02.039

1879-0445

Stephany El‐Hayek, Qin Yang, Laleh Abbassi, Greg FitzHarris, Hugh J. Clarke,

Renal and related cancers

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Burns K.H. Viveiros M.M. Eppig J.J. Intercellular communication in the mammalian ovary: oocytes carry the conversation.Science. 2002; 296: 2178-2180Crossref PubMed Scopus (739) Google Scholar]. Identifying the mechanisms underlying their formation should uncover conserved regulators of fertility. We show here in mice that these structures, termed transzonal projections (TZPs), are specialized filopodia whose number amplifies enormously as oocytes grow, enabling increased germ-soma communication. By creating chimeric complexes of genetically tagged oocytes and follicle cells, we demonstrate that follicle cells elaborate new TZPs that push through the extracellular coat to reach the oocyte surface. We further show that growth-differentiation factor 9, produced by the oocyte, drives the formation of new TZPs, uncovering a key yet unanticipated role for the germ cell in building these essential bridges of communication. Moreover, TZP number and germline-soma communication are strikingly reduced in reproductively aged females. Thus, the growing oocyte locally remodels follicular architecture to ensure that its developmental needs are met, and an inability of somatic follicle cells to respond appropriately to oocyte-derived cues may contribute to human infertility.