Somatic cell nuclear transfer (SCNT) is the most efficient cell reprogramming technique available, especially when working with bovine species. Although SCNT blastocysts performed equally well or better than controls in the weeks following embryo transfer at Day 7, elongation and gastrulation defects were observed prior to implantation. To understand the developmental implications of embryonic/...

The establishment of a receptive uterine environment is critical for embryonic survival and implantation. One gene that is expressed in the uterus during the peri-implantation period in mice and is required for female fertility is the homeobox gene Hoxa-10. Here we characterize the peri-implantation defects in Hoxa-10 mutant females and investigate functions of Hoxa-10 in the uterine anlage dur...

Ultrasonography is a powerful tool to non-invasively monitor in real time the development of the human fetus in utero. Although genetically engineered mice have served as valuable in vivo models to study both embryo implantation and pregnancy progression, such studies usually require sacrifice of parous mice for subsequent phenotypic analysis. To address this issue, we used three-dimensional (3...

Insulin like growth factors (IGF-I and IGF-II) are expressed in embryos and reproductive tracts of several species including cow, sheep and swine. They are mitogenic and have endocrine, paracrine and autocrine function infusing cell division, blastocyst formation, implantation and embryo growth. Increase in embryo growth will probably result with a higher implantation rates leading to consequen...

Cloning mammals by somatic cell nuclear transfer (SCNT) is highly inefficient. Most SCNT-generated embryos die after implantation because of unidentified, complex epigenetic errors in the process of postimplantation embryonic development. Here we identify the most upstream level of dysfunction leading to impaired development of clones by using RNAi against Xist, a gene responsible for X chromos...

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and are a major cause of spontaneous miscarriage or birth defects. Nonetheless, model systems suitable for the study of ...

Implantation of the embryo is critical for the initiation of intrauterine development of early embryos. It depends on the proper soil formed by the decidualized pregnant uterus. In the present article I have reviewed the evolution of the modern concepts of decidualization and embryonic implantation, emphasizing how closely interrelated these two processes are. Special emphasis and recognition i...

Understanding human pre-implantation development has important implications for assisted reproductive technology (ART) and for human embryonic stem cell (hESC)-based therapies. Owing to limited resources, the cellular and molecular mechanisms governing this early stage of human development are poorly understood. Nonetheless, recent advances in non-invasive imaging techniques and molecular and g...

Epigenetics regulations have an important role in fertilization and proper embryonic development, and several human diseases are associated with epigenetic modification disorders, such as Rett syndrome, Beckwith-Wiedemann syndrome and Angelman syndrome. However, the dynamics and functions of long non-coding RNAs (lncRNAs), one type of epigenetic regulators, in human pre-implantation development...

The majority of cloned animals derived by nuclear transfer from somatic cell nuclei develop to the blastocyst stage but die after implantation. Mouse embryos that lack an Oct4 gene, which plays an essential role in control of developmental pluripotency, develop to the blastocyst stage and also die after implantation, because they lack pluripotent embryonic cells. Based on this similarity, we po...