Relocalization of small ribonucleoprotein particles (snRNPs) during the first cell cycle of mouse embryo development is independent of RNA synthesis, DNA synthesis and cytokinesis.
The process of localization of small nuclear ribonucleoprotein particles (snRNPs) during the first cell cycle of mouse embryo development was investigated following treatment of fertilized eggs with cytochalasin D, aphidicolin and alpha-amanitin. The pattern of accumulation of snRNPs in nuclei of treated embryos as assessed by indirect immunofluorescence was unaffected by the inhibitors. The results demonstrate that the localization of snRNPs during the first cell cycle does not require ongoing cytokinesis, DNA replication or transcription of RNA polymerase II genes. These findings suggest that maternally derived snRNPs become localized to the nucleus of the fertilized ovum prior to the reinitiation of transcription from the zygote genome and are required for processing of messenger RNA precursors when genetic activity of the embryonic genome is activated at the early 2-cell stage.
Dean
W L
WL
Department of Medical Biochemistry, University of Calgary, Alberta, Canada.
Schultz
G A
GA
D000546:Amanitins / Q000494:pharmacology; D000818:Animals; D016590:Aphidicolin; D001692:Biological Transport; D002451:Cell Compartmentation; D002453:Cell Cycle / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002467:Cell Nucleus / Q000378:metabolism; D015638:Cytochalasin D / Q000494:pharmacology; D004257:DNA Polymerase II / Q000037:antagonists & inhibitors; D004261:DNA Replication / Q000187:drug effects; D004224:Diterpenes / Q000494:pharmacology; D005314:Embryonic and Fetal Development / Q000502:physiology*; D051379:Mice; D014176:Protein Biosynthesis; D012261:Ribonucleoproteins / Q000378:metabolism*; D017411:Ribonucleoproteins, Small Nuclear; D014158:Transcription, Genetic / Q000187:drug effects; D015053:Zygote / Q000378:metabolism
D000546:Amanitins; D004224:Diterpenes; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; D015638:Cytochalasin D; D016590:Aphidicolin; D004257:DNA Polymerase II