• sperm
  • After fertilization some cells of the newly formed embryo migrate to the germinal ridge and will eventually become the germ cells (sperm and oocytes). (wikipedia.org)
  • When the sperm fertilizes the egg, the sperm nucleus and centrosomes are deposited within the egg, which causes a cytoplasmic flux resulting in the movement of the sperm pronucleus and centrosomes towards one pole. (wikipedia.org)
  • The centrosomes deposited by the sperm seem to be responsible for the establishment of the posterior pole within the one cell embryo. (wikipedia.org)
  • Eggan's technique provides a window into exactly what happens to turn back the clock in cells during cloning--and, indeed, in the normal process of creating sperm, eggs and embryos. (wikipedia.org)
  • Embryo development begins with a sperm fertilizing an egg to become a zygote which undergoes many cleavages to develop into a ball of cells called a morula. (wikipedia.org)
  • fetal
  • In January 2018, a team of scientists in Shanghai announced the successful cloning of two female crab-eating macaques (named Zhong Zhong and Hua Hua) from fetal nuclei. (wikipedia.org)
  • They extracted nuclei from the fibroblasts of an aborted fetal monkey (a crab-eating macaque or Macaca fascicularis) and inserted them into egg cells (ova) that had had their own nuclei removed. (wikipedia.org)
  • vertebrate
  • In the vertebrate embryo, a rhombomere is a transiently divided segment of the developing neural tube, within the hindbrain region (a neuromere) in the area that will eventually become the rhombencephalon. (wikipedia.org)
  • stage
  • A wave of methylation then takes place during the implantation stage of the embryo, with CpG islands protected from methylation. (wikipedia.org)
  • After fertilization, events are already occurring in the one cell stage embryo to allow for the first asymmetric cell division. (wikipedia.org)
  • The blastula stage of early embryo development begins with the appearance of the blastocoele. (wikipedia.org)
  • In many organisms the development of the embryo up to this point and for the early part of the blastula stage is controlled by maternal mRNA, so called because it was produced in the egg prior to fertilization and is therefore exclusively from the mother. (wikipedia.org)
  • cells
  • Eggan's research goals at Harvard were to understand how nuclear transplantation works, and to make stem cells that carry genes for specific diseases such as Parkinson's disease, amyotrophic lateral sclerosis (Lou Gehrig's disease), and Alzheimer's. (wikipedia.org)
  • Eggan's work as of 2007[update] has succeeded in developing a technique of merging stem and skin cells that has obtained considerable public attention as a possible avenue to avoid moral objections regarding stem cell research in the context of serious illness. (wikipedia.org)
  • Embryomics is the identification, characterization and study of the diverse cell types which arise during embryogenesis, especially as this relates to the location and developmental history of cells in the embryo. (wikipedia.org)
  • These cell markers consist of select RNAs and proteins present inside, and surface antigens present on the surface of, the cells making up the embryo. (wikipedia.org)
  • The entire process of embryogenesis can be described with the aid of two maps: an embryo map, a temporal sequence of 3-dimensional images of the developing embryo, showing the location of cells of the many cell types present in the embryo at a given time, and an embryogenic tree, a diagram showing how the cell types are derived from each other during embryogenesis. (wikipedia.org)
  • The addition of the two growth phases into the cell cycle allows for the cells to increase in size, as up to this point the blastomeres undergo reductive divisions in which the overall size of the embryo does not increase, but more cells are created. (wikipedia.org)
  • tissues
  • In her work with chick embryos, Margaret Lewis studied connective tissue formation within the tissues as well as outside of an environment where factors involved in coagulation are present. (wikipedia.org)
  • stem cell
  • Eggan began to explore both this process and also the reasons that cloned animals often appeared to develop abnormally, with organ defects and immunological problems - his first contact with stem cell research. (wikipedia.org)
  • At the time, stem cell research in the United States was threatened by political pressure due to concerns over the ethics of human embryo research, and research such as this was at risk of potentially being made illegal. (wikipedia.org)
  • Federal funding for stem cell research had recently been removed, and part of his role was to obtain private funding to replace it. (wikipedia.org)
  • It suggests that ultimately, treatment of serious illnesses and understanding of stem cell development may be possible to obtain without recourse to human embryos - a highly desirable state of affairs politically, given the concurrent controversy over stem cell research in the United States. (wikipedia.org)
  • The study of the blastula and of cell specification has many implications on the field of stem cell research as well as the continued improvement of fertility treatments. (wikipedia.org)
  • species
  • However, instead of each branch on this tree representing a species, as in the tree of life, each branch represents a particular cell type present in the embryo at a particular time. (wikipedia.org)
  • shown
  • In vitro manipulation of pre-implantation embryos has been shown to disrupt methylation patterns at imprinted loci and plays a crucial role in cloned animals. (wikipedia.org)
  • Vestibular nuclei have been shown to span all the rhombomeres, some correlating with the boundaries of the rhombomeres. (wikipedia.org)
  • work
  • The groups initially collaborated in researching diabetes before Eggan's group switched to work on neurodegenerative diseases. (wikipedia.org)
  • Based on the publication of this work, Morgan was awarded his Ph.D. from Johns Hopkins in 1890, and was also awarded the Bruce Fellowship in Research. (wikipedia.org)
  • procedure
  • She is the first "cloned" primate by artificial twinning, which is a much less complex procedure than the DNA transfer used for the creation of Zhong Zhong and Hua Hua. (wikipedia.org)
  • development
  • The embryogenic tree is a diagram which shows the temporal development of each of the cell lines in the embryo. (wikipedia.org)
  • In many animals such as Drosophila and Xenopus, the mid blastula transition (MBT) is a crucial step in development during which the maternal mRNA is degraded and control over development is passed to the embryo. (wikipedia.org)
  • There he worked with German biologist Hans Driesch, whose research in the experimental study of development piqued Morgan's interest. (wikipedia.org)
  • form
  • The blastula precedes the formation of the gastrula in which the germ layers of the embryo form. (wikipedia.org)
  • Freezing does not start until the temperature is low enough to provide enough energy to form stable nuclei. (wikipedia.org)
  • factors
  • As a result, this couple's greatest impact on embryology and cell biology in the twentieth century was teaching later generations of biologists the basic factors involved in tissue culture based on what they had learned from their research. (wikipedia.org)
  • likely
  • Margaret Adaline Reed Lewis (1881-1970) was an American cell biologist and embryologist who made contributions to cancer research and cell culture techniques, and was likely the first person to successfully grow mammalian tissue in vitro. (wikipedia.org)
  • time
  • The embryo map is a sequence of 3-D images, or slices of 3-D images, of the developing embryo which, if viewed rapidly in temporal order, forms a time-lapse view of the growing embryo. (wikipedia.org)
  • surface
  • If a hypothetical nucleus is too small, the energy that would be released by forming its volume is not enough to create its surface, and nucleation does not proceed. (wikipedia.org)
  • study
  • With so many avenues opened by cell culture to explore, Margaret Lewis and her husband diverged in their area of study, with Margaret Lewis choosing to focus on microbiological problems, which involved close observations of chick embryo intestines reacting to typhoid bacilli in the medium in which it was grown. (wikipedia.org)