Abstract
Several equids have gone extinct and many extant equids are currently considered vulnerable to critically endangered. This work aimed to evaluate whether domestic horse oocytes support preimplantation development of zebra embryos obtained by intracytoplasmic sperm injection (ICSI, zebroid) and cloning, and to study the Hippo signaling pathway during the lineage specification of trophectoderm cells and inner cell mass cells. We first showed that zebra and horse sperm cells induce porcine oocyte activation and recruit maternal SMARCA4 during pronuclear formation. SMARCA4 recruitment showed to be independent of the genetic background of the injected sperm. No differences were found in blastocyst rate of ICSI hybrid (zebra spermatozoon into horse egg) embryos relative to the homospecific horse control group. Interestingly, zebra cloned blastocyst rate was significantly higher at day 8. Moreover, most ICSI and cloned horse and zebra blastocysts showed a similar expression pattern of SOX2 and nuclear YAP1 with the majority of the nuclei positive for YAP1, and most SOX2+ nuclei negative for YAP1. Here we demonstrated that horse oocytes support zebra preimplantation development of both, ICSI and cloned embryos, without compromising development to blastocyst, blastocyst cell number neither the expression of SOX2 and YAP1. Our results support the use of domestic horse oocytes as a model to study in vitro zebra embryos on behalf of preservation of valuable genetic.
Highlights
IntroductionWild asses, zebras and Przewalski’s horses share the only extant genus of the family Equidae: the genus Equus
Domestic horses and donkeys, wild asses, zebras and Przewalski’s horses share the only extant genus of the family Equidae: the genus Equus
One day 11 hatched zebroid blastocyst had a different YAP1 expression pattern (Fig 3C). This embryo, with higher cell number and an advanced developmental stage, showed a lower percentage of YAP1+ nuclei. These results suggest that heterospecific reprogramming of zebra sperm cells by domestic horse oocytes might not affect the localization of YAP1 and SOX2 compared to the homospecific counterpart
Summary
Wild asses, zebras and Przewalski’s horses share the only extant genus of the family Equidae: the genus Equus. Efforts for the preservation of wild equids are needed for the maintenance of animal population and genetic variability among individuals. To accomplish these goals, in addition to natural breeding, conservation programs can be enhanced by using assisted reproductive techniques (ART) to achieve optimal genetic management of endangered species and overcome infertility issues [7, 8]. Hybridization within equids is well known in vivo, to the best of our knowledge, there are no reports on in vitro production of hybrid equid embryos through ICSI This could be a powerful tool to generate knowledge about the fertilization, genetics and early embryo development processes in these species. The number of cloned horses produced by somatic cell nuclear transfer (SCNT) has significantly increased over the last few years since the first cloned horse [17]; cloning efficiency remains poor [18]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call