Study of sperm histone modifications and its relationship with bull in vitro fertility

• Grant number: 17/12891-8
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: September 15, 2017
• End date: August 14, 2018
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Mayra Elena Ortiz D' Avila Assumpcao
• Grantee: Letícia Signori de Castro
• Supervisor: Pablo Juan Ross
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of California, Davis (UC Davis), United States
• Associated to the scholarship: 15/14146-2 - Study of protein and epigenetic profile of bovine sperm nucleus with effect on in vitro embryo production, BP.DR

Abstract

The mature spermatozoa present a unique chromatin compaction that allows the protection of paternal DNA during the route until the oocyte. This high degree of compaction is characterized by protamine-DNA binding, the nuclear protein that replaces histone during spermatogenesis. However, some specific regions of the sperm chromatin remain bound to nucleosomes composed of histones. In humans, it has already been verified that atypical distribution of these histones leads to embryo development failures. In cattle, little is known about the role of the remaining histones in sperm DNA, as well as the importance of sperm epigenetic marks to the embryo. Thus, it is possible to assume that the genes and promoter regions in which these histones are bound to sperm chromatin may interfere or even define the success or not of the in vitro embryo production of a particular bull. Therefore, this study proposes to evaluate 2 histones modifications, H3K4me3 and H3K27me3 between bulls of high and low in vitro fertility in an attempt to identify which genes and promoter regions are differently enriched between these groups and that could explain the difference for in vitro embryo production.