Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2004-8-4
pubmed:abstractText
Here we present ultrastructural and immunocytochemical evidence that ovine ooplasm is directing the initial assembly of the nucleolus independent of the species of the nuclear donor. Intergeneric porcine-ovine somatic cell nuclear transfer (SCNT) and intrageneric ovine-ovine SCNT embryos were constructed and the nucleolus ultrastructure and nucleolus associated rRNA synthesis examined in 1-, 2-, 4-, early 8-, late 8-, and 16-cell embryos using transmission electron microscopy (TEM) and light microscopical autoradiography. In addition, immunocytochemical localization by confocal microscopy of nucleolin, a key protein involved in processing rRNA transcripts, was performed on early 8-, late 8-, and 16-cell embryos for both groups of SCNT embryos. Intergeneric porcine-ovine SCNT embryos exhibited nucleolar precursor bodies (NPBs) of an ovine (ruminant) ultrastructure, but no active rRNA producing fibrillo-granular nucleoli at any of the stages. Unusually, cytoplasmic organelles were located inside the nucleus of two porcine-ovine SCNT embryos. The ovine-ovine SCNT embryos, on the other hand, revealed fibrillo-granular nucleoli in 16-cell embryos. In parallel, autoradiographic labeling over the nucleoplasm, and in particular, the nulcleoli was detected. Bovine-ovine SCNT embryos at the eight-cell stage were examined for nucleolar morphology and exhibited ruminant-type NPBs as well as structures that appeared as fibrillar material surrounded by a rim of electron dense granules, perhaps formerly of nucleolar origin. Nucleolin was localized throughout the nucleoplasm and with particular intensity around the presumptive nucleolar compartments for all developmental stages examined in porcine-ovine and ovine-ovine SCNT embryos. In conclusion, this study suggests that factors within the ovine ooplasm are playing a role in the initial assembly of the embryonic nucleolus in intrageneric SCNT embryos.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1040-452X
pubmed:author
pubmed:issnType
Print
pubmed:volume
69
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
117-25
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:15293212-Animals, pubmed-meshheading:15293212-Autoradiography, pubmed-meshheading:15293212-Cattle, pubmed-meshheading:15293212-Cell Nucleolus, pubmed-meshheading:15293212-Cloning, Organism, pubmed-meshheading:15293212-Cytoplasm, pubmed-meshheading:15293212-Embryo, Mammalian, pubmed-meshheading:15293212-Immunohistochemistry, pubmed-meshheading:15293212-Microscopy, Confocal, pubmed-meshheading:15293212-Microscopy, Electron, Transmission, pubmed-meshheading:15293212-Nuclear Transfer Techniques, pubmed-meshheading:15293212-Oocytes, pubmed-meshheading:15293212-Phosphoproteins, pubmed-meshheading:15293212-RNA, Ribosomal, pubmed-meshheading:15293212-RNA-Binding Proteins, pubmed-meshheading:15293212-Sheep, pubmed-meshheading:15293212-Species Specificity, pubmed-meshheading:15293212-Swine
pubmed:year
2004
pubmed:articleTitle
Ovine ooplasm directs initial nucleolar assembly in embryos cloned from ovine, bovine, and porcine cells.
pubmed:affiliation
Turretfield Research Centre, South Australian Research and Development Institute, Rosedale, South Australia, Australia. hamish.hamilton@helsinki.fi
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't