Abstract

TARAZONA¹, ARIEL; LOPEZ, ANGELA  and  OLIVERA-ANGEL, MARTHA. The Oocite Competence:: What, How and When. Acta biol.Colomb. [online]. 2010, vol.15, n.3, pp.3-18. ISSN 0120-548X.

The in vitro production of embryos has been a useful tool for the development of techniques such as cloning and transgenesis, which have revolutionized the fields of science and technology. The basic technique for maturation, fertilization and in vitro culture of embryos produced from the beginning, low rates of development to the blastocyst stage and reduced viability of these. Advances in the understanding of cellular dynamics during these processes led to the hypothesis that the maturation, defined as the resumption of the meiotic cycle, ooplasma reorganization and regulation of gene expression, play a key role in sustaining early development on the embryos, this ability to achieve development is called competence. The acquisition of nuclear and cytoplasmic competition takes place over two clear phases of development of the oocyte, the first is the growth, where occur molecular arrangements and organelles reorganization into the ooplasma and the second phase, in which ocurr the restart of meiosis to achieve finally the haploid number of chromosomes that will be complemented by the paternal to the development of a new individual. The aim of this review is to describe the cellular and molecular processes that lead to the acquisition of competence of the oocyte, including: cytoplasmic maturation, resumption of meiosis and the interactions between the oocyte, cumulus cells and follicular fluid. The subject is presented in three parts: 1. follicular development of the complex, 2. Oocyte growth and intracellular remodeling and 3. Nuclear maturation. It concludes with a model of intercellular communication and regulation, to explain this intricate complex as it involves different signaling pathways.

Keywords : follicular complex; maturation; meiosis; ooplasm.

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