Reproduction Abstracts

In several mammalian species, a major remodelling of the germinal vesicle chromatin is known to occur towards the end of the oocyte growth. Various chromatin configurations have been identified. However, the mechanisms involved in this remodelling process are yet not completely understood. In the bovine species, four distinct and progressive states of chromatin compaction have been characterized and are linked to a gradual acquisition of the developmental potential. Germinal v...

Introduction: Several studies support the notion that in vitro pre-maturation treatments aimed to improve the developmental capability of immature oocytes have a different effect depending on the oocyte metabolic status at the time of its removal from the follicle. We demonstrated that changes in large-scale chromatin configuration within the germinal vesicle (GV) of fully-grown bovine oocytes are related to the acquisition of developmental competence. In particular, ...

Introduction: Previous studies suggest that progesterone receptor membrane component 1 (PGRMC1) plays an essential role during bovine oocyte meiosis, since it i) localizes to the centromeres at metaphases I and II and ii) concentrates between the separating chromosomes at ana/telophase I. Moreover, injection of an antibody to PGRMC1 significantly impairs completion of meiosis. The aim of the present study is to expand these findings by using siRNA (RNAi)-mediated gene silencin...

Introduction: We recently demonstrated that in vitro maturation (IVM) is associated with defects in histone H4 lysine 16 (H4K16) acetylation in horse oocytes, together with a higher incidence of spindle anomalies and aneuploidy. In the present study we investigated whether maturation conditions can alter the abundance of transcripts involved in histone acetylation and deacetylation. The specific H4K16 acetyl-transferase Myst1, the general acetyl-transferase <...