title: [Localization of ribosomal genes and nucleolar activity in lymphocytes of swine (Sus scrofa domestica) stimulated by phytohemagglutinins].
abstract: The Pig chromosomes that contain rDNA sites displayed a polymorphism in the distribution of the genes among the nucleolar organizers located on pairs Nos. 8 and 10. Two, or more often three, active sites were observed in the chromosomes of lymphocytes stimulated with phytohemagglutinin. Only 5% of the metaphases showed a 4th small active site. At the onset of stimulation most cells contained one-two nucleoli; four nucleoli were never observed. After prolonged stimulation, the number of nuclei containing three nucleoli increased. A 4th small nucleolus appeared in a few cells, presumably formed by activation of the smallest rDNA site.
mesh_terms: D000818:Animals; D002466:Cell Nucleolus / Q000502:physiology*; D004247:DNA / Q000235:genetics*; D004275:DNA, Ribosomal; D007621:Karyotyping; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology / Q000502:physiology*; D009693:Nucleic Acid Hybridization; D010835:Phytohemagglutinins; D012270:Ribosomes / Q000502:physiology; D013552:Swine
chemical_list: D004275:DNA, Ribosomal; D010835:Phytohemagglutinins; D004247:DNA
vernacular_title: Localisation des gènes ribosomiques et activité nucléolaire dans les lymphocytes du Porc (Sus scrofa domestica) stimulés par la phytohémagglutinine.