The article is a review entitled "Omne vivum ex ovo: the oocyte reprogramming and remodelling activities", and its aim was to clarify the mutual interactions of the individual components of the oocyte with its natural partner cell (sperm) or "unnatural" somatic nucleus, and thus to provide a better understanding of the process of totipotency and define the requirements for normal development of the embryo.
Researchers from the University of Teramo, Gurdon Institute – University of Cambridge and the Institute of Animal Science in Prague also participated in this paper.
The mammalian oocyte is a unique cell, and comprehending its physiology and biology is essential for understanding the fertilization, totipotency and early events of embryogenesis. Consequently, research in these areas influences the outcomes of various technologies, for example, the production and conservation of laboratory and large animals with rare and valuable genotypes, the rescue of species near extinction, as well as success in human assisted reproduction. Nevertheless, even the most advanced and sophisticated reproductive technologies today do not always guarantee a favourable outcome. Elucidating the interactions of oocyte components with its natural partner cell - the sperm or an "unnatural" somatic nucleus, when the somatic cell nucleus transfer is used is essential for understanding how totipotency is established and thus defining the requirements for normal development. One of the crucial aspects is the stoichiometry of different reprogramming and remodelling factors present in the oocyte and their balance. Here, we discuss how these factors, in combination, may lead to the formation of a new organism. We focus on the laboratory mouse and its genetic models, as this specie has been instrumental in shaping our understanding of early post-fertilization events.