Epigenetic maturation of the oocyte and totipotence: the potential of the oocyte and its relationship with the ovarian follicular niche

Abstract

The epigenetic mechanisms governing the ability of the female gamete, i.e. the oocyte, to become totipotent are at the center of many unanswered questions in biology and a better understanding of such a basic phenomenon offers a unique opportunity to develop novel biotechnologies with wide-reaching benefits for humans and animals. This thematic project brings together renowned Canadian and Brazilian experts working in a wide range of scientific fields from the subcellular to the whole organismal levels, who together aim to tackle the yet unanswered question in biology, i.e. what are the epigenetic cues provided by the follicular environment that enable the production of an oocyte capable of deriving all cells in an organism, including its perpetuation through the production of gametes for the next generation? Through the use of sophisticated retrospective approaches with state-of-the-art bioinformatic tools to analyze the epigenetic components at the molecular and cellular levels, a series of unique experimental models are aimed to (1) identify key molecular constituents involved in the oocyte-follicle interactions, (2) intervene on the meiotic resumption in vitro to simulate in vivo folliculogenesis, and (3) examine alternative models to unveil essential mechanisms of totipotency. The sharing of complementary know-how among the Canadian and Brazilian teams provides a distinctive opportunity to shed further light on fundamental mechanisms controlling the acquisition of totipotency by the oocyte. As practical relevance, humans and animals will benefit directly through the improvement and advent of novel assisted reproductive biotechniques that improve procreation in infertile couples, accelerate the dissemination of superior genotypes in domestic species, and restore threatened wildlife. (AU)