Blocking connexin channels improves embryo development of vitrified bovine blastocysts.

Connexins (Cxs) are required for normal embryo development and implantation. They form gap junctions (GJs) connecting the cytoplasm of adjacent cells and hemichannels (HCs), which are normally closed but open in response to stress conditions. Excessive HC opening is detrimental for cell function and may lead to cell death.

Determination of the parental pronuclear origin in bovine zygotes: H3K9me3 versus H3K27me2-3.

To study the dynamics of 5-methylcytosine and 5-hydroxymethylcytosine in zygotes, the parental origin of the pronuclei needs to be determined. To this end the use of the asymmetric distribution of histone modifications in pronuclei is becoming more popular. Here, we demonstrated that histone 3 lysine 27 di-tri-methylation shows a stable pattern being present in the maternal but not in the paternal pronucleus of bovine zygotes, even in late stages of pronuclear development.

Equine oviduct explant culture: a basic model to decipher embryo-maternal communication.

Equine embryos remain for 6 days in the oviduct and thus there is a need for an in vitro model to study embryo-oviductal interactions in the horse, since this subtle way of communication is very difficult to analyse in vivo. Until now, no equine oviduct explant culture model has been characterised both morphologically and functionally. Therefore, we established a culture system for equine oviduct explants that maintained epithelial morphology during 6 days of culture, as revealed by light microscopy and transmission electron microscopy.