Dynamics of RNA expression and epigenetic changes during bovine oocyte maturation and embryonic development: comparing in vivo and in vitro systems

• Grant number: 15/21674-5
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): November 01, 2015
• Effective date (End): October 31, 2017
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal researcher: Juliano Coelho da Silveira
• Grantee: Rosane Mazzarella
• Home Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated research grant: 14/22887-0 - Cell-secreted vesicles containing miRNAs modulate epigenetic changes during in vitro culture of bovine gametes and embryos, AP.JP

Abstract

Assisted reproductive technologies are an alternative to solve reproductive problems in domestic animals and humans. However, there is a concern that in vitro culture of gametes and embryos could generate epigenetic changes, which may lead to a higher predisposition to health problems in adulthood. Epigenetic changes are regulated by DNA methylation, by post-translational modifications of histones or microRNAs (miRNA). MiRNAs are non-protein-coding RNAs that regulate gene expression. Recently, cell- secreted vesicles containing miRNAs called exosomes and microvesicles were found in different body fluids. These vesicles are considered a new class of intercellular communication with possible implications in different physiological processes. However, their role in the acquisition of gamete competence and embryo development is still largely unknown. The hypothesis, which will be tested, is that in vitro oocyte maturation and embryo development generate changes in the levels of miRNAs. To test this hypothesis, total RNA will be isolated from oocytes and embryos produced in vitro and in vivo. The objective is to determine the relationship between miRNAs and epigenetic changes acquired during maturation of oocytes and embryo development in cattle. The results of this project will allow better understanding and developing similar protocols to the physiological condition for the in vitro production of embryos, with great impact on the assisted reproduction industry in cattle and humans.