Despite extensive efforts, low efficiency is still an issue in bovine somatic cell nuclear transfer (SCNT). The hypothesis of our study was that the use of cytoplasts produced by chemically assisted enucleation (EN) would improve nuclear reprogramming in nuclear transfer (NT)-derived embryos because it results in lower damage and higher cytoplasm content than conventional EN. For that purpose, ...

Epigenetic reprogramming is thought to play an important role in the development of cloned embryos reconstructed by somatic cell nuclear transfer (SCNT). In the present study, dynamic reprogramming of histone acetylation and methylation modifications was investigated in the first cell cycle of cloned embryos. Our results demonstrated that part of somatic inherited lysine acetylation on core his...

Cloning by somatic cell nuclear transfer (SCNT) subverts sperm-mediated fertilization that normally leads to physiological activation of the oocyte. Therefore, artificial activation is required and it is presently unclear what developmental consequences this has. In this study, we aimed to improve cattle cloning efficiency by utilizing a more physiological method of activating SCNT reconstructs...

Background Despite successful cloning of many mammalian species, the cloning efficiency is extremely low compared to that of IVF raising the possibility of the existence of epigenetic barrier preventing successful cloning. MaterialsAndMethods Using comparative transcriptome analysis comparing transcriptomes of IVF and SCNT embryos and that of donor cells, we identified epigenetic barrier and fi...

Although somatic cell nuclear transfer (SCNT) and induction of pluripotency (to form iPSCs) are both recognized reprogramming methods, there has been relatively little comparative analysis of the resulting pluripotent cells. Here, we examine the capacity of these two reprogramming approaches to rejuvenate telomeres using late-generation telomerase-deficient (Terc(-/-)) mice that exhibit telomer...

BACKGROUND Over the last decade a number of species, from farm animals to rodents, have been cloned using somatic cell nuclear transfer technology (SCNT). This technique has the potential to revolutionize the way that genetically modified animals are made. In its current state, the process of SCNT is very inefficient (<5% success rate), with several technical and biological hurdles hindering de...

Early studies on cloning of non-human primates by nuclear transfer utilized embryonic blastomeres from preimplantation embryos which resulted in the reproducible birth of live offspring. Soon after, the focus shifted to employing somatic cells as a source of donor nuclei (somatic cell nuclear transfer, SCNT). However, initial efforts were plagued with inefficient nuclear reprogramming and poor ...

The selection of good quality oocytes is crucial for in vitro fertilization and somatic cloning. Brilliant cresyl blue (BCB) staining has been used for selection of oocytes from several mammalian species. However, the effects of differential oocyte selection by BCB staining on nuclear reprogramming and in vivo development of SCNT embryos are not well understood. Immature compact cumulus-oocyte ...

Epigenetic reprogramming is necessary in somatic cell nuclear transfer (SCNT) embryos in order to erase the differentiation-associated epigenetic marks of donor cells. However, such epigenetic memories often persist throughout the course of clonal development, thus decreasing cloning efficiency. Here, we explored reprogramming-refractory regions in bovine SCNT blastocyst transcriptomes. We obse...

Abnormal epigenetic reprogramming of donor nuclei after somatic cell nuclear transfer (SCNT) is thought to be the main cause of low cloning efficiencies. A growing body of evidence has demonstrated a positive role of Scriptaid, a histone deacetylase inhibitor (HDACi) that belongs to an existing class of hydroxamic acid-containing HDACis, on the development competence of cloned embryos in many s...