title: Preimplantation development of somatic cell cloned embryos in the common marmoset (Callithrix jacchus).
abstract: The somatic cell nuclear transfer technique has been applied to various mammals to produce cloned animals; however, a standardized method is not applicable to all species. We aimed here to develop optimum procedures for somatic cell cloning in nonhuman primates, using common marmosets. First, we confirmed that parthenogenetic activation of in vitro matured oocytes was successfully induced by electrical stimulation (three cycles of 150 V/mm, 50 microsec x 2, 20 min intervals), and this condition was applied to the egg activation procedure in the subsequent experiments. Next, nuclear transfer to recipient enucleated oocytes was performed 1 h before, immediately after, or 1 h after egg activation treatment. The highest developmental rate was observed when nuclear transfer was performed 1 h before activation, but none of the cloned embryos developed beyond the eight-cell stage. To investigate the causes of the low developmental potential of cloned embryos, a study was performed to determine whether the presence of metaphase II (MII) chromosome in recipient ooplasm has an effect on developmental potential. As a result, only tetraploid cloned embryos produced by transferring a donor cell into a recipient bearing the MII chromosome developed into blastocysts (66.7%). In contrast, neither parthenogenetic embryos nor cloned embryos (whether diploid or tetraploid) produced using enucleated oocytes developed past the eight-cell stage. These results suggest that MII chromosome, or cytoplasm proximal to the MII chromosome, plays a major role in the development of cloned embryos in common marmosets.
authors.affiliation: Natural Science Center for Basic Research and Development, Hiroshima University, Hiroshima, Hiroshima, Japan. sotomaru@hiroshima-u.ac.jp
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Sotomaru
authors.forename: Reiko
authors.initials: R
authors.lastname: Hirakawa
authors.forename: Akiko
authors.initials: A
authors.lastname: Shimada
authors.forename: Seiji
authors.initials: S
authors.lastname: Shiozawa
authors.forename: Ayako
authors.initials: A
authors.lastname: Sugawara
authors.forename: Ryo
authors.initials: R
authors.lastname: Oiwa
authors.forename: Asako
authors.initials: A
authors.lastname: Nobukiyo
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Okano
authors.forename: Norikazu
authors.initials: N
authors.lastname: Tamaoki
authors.forename: Tatsuji
authors.initials: T
authors.lastname: Nomura
authors.forename: Eiso
authors.initials: E
authors.lastname: Hiyama
authors.forename: Erika
authors.initials: E
authors.lastname: Sasaki
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology* / Q000502:physiology; D002144:Callithrix; D002467:Cell Nucleus / Q000502:physiology; D033481:Chromosomes, Mammalian / Q000502:physiology*; D019976:Cloning, Organism / Q000379:methods; D003593:Cytoplasm / Q000502:physiology*; D010064:Embryo Implantation; D047108:Embryonic Development; D005260:Female; D008297:Male; D008677:Metaphase / Q000502:physiology*; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000166:cytology* / Q000502:physiology; D010312:Parthenogenesis