The development and expression of pluripotency genes in embryos derived from nuclear transfer and in vitro fertilization. Issue 4 (November 2014)

• Record Type: Journal Article
• Authors: Ma, Li-Bing; He, Xiao-Ying; Wang, Feng-Mei; Cao, Jun-Wei; Cheng, Teng
• Is Part Of: Zygote. Volume 22:Issue 4(2014)
• Page Start: 540
• Page End: 548
• Publication Date: 2014-11
• Subjects: Developmental biology -- Periodicals; Embryology -- Periodicals; Zygotes -- Periodicals; Gametes -- Periodicals; 571.864
• DOI: 10.1017/S0967199413000129
• Languages: English
• ISSNs: 0967-1994

Abstract

<abstract abstract-type="normal"> <title>Summary</title> <p>Somatic cell nuclear transfer can be used to produce embryonic stem (ES) cells, cloned animals, and can even increase the population size of endangered animals. However, the application of this technique is limited by the low developmental rate of cloned embryos, a situation that may result from abnormal expression of some zygotic genes. In this study, sheep–sheep intra-species cloned embryos, goat–sheep inter-species cloned embryos, or sheep <italic>in vitro</italic> fertilized embryos were constructed and cultured <italic>in vitro</italic> and the developmental ability and expression of three pluripotency genes, <italic>SSEA-1</italic>, <italic>Nanog</italic> and <italic>Oct4</italic>, were examined. The results showed firstly that the developmental ability of <italic>in vitro</italic> fertilized embryos was significantly higher than that of cloned embryos. In addition, the percentage of intra-species cloned embryos that developed to morula or blastocyst stages was also significantly higher than that of the inter-species cloned embryos. Secondly, all three types of embryos expressed SSEA-1 at the 8-cell and morula stages. At the 8-cell stage, a higher percentage of <italic>in vitro</italic> fertilized embryos expressed SSEA-1 than occurred for cloned embryos. However, at the morula stage, all detected embryos could express SSEA-1. Thirdly, the three types of embryos expressed <italic>Oct4</italic> mRNA at the morula and blastocyst stages, and embryos at the blastocyst stage expressed <italic>Nanog</italic> mRNA. The rate of expression of <italic>Oct4</italic> and <italic>Nanog</italic> mRNA at these developmental stages was higher in <italic>in vitro</italic> fertilized embryos than in cloned embryos. These results indicated that, during early development, the failure to reactivate some pluripotency genes maybe is a reason for the low cloning efficiency found with cloned embryos.</p> </abstract>