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The germinal vesicle of the Xenopus oocyte contains 1500 or more extrachromosomal nucleoli that are assembled on amplified copies of the rRNA genes. Many of these nucleoli have diameters of 10-15 micron, but some are much smaller, ranging down to 1 micron or less. Morphologically the smaller nucleoli or "micronucleoli" resemble the similarly sized B snurposomes, but they can be recognized with appropriate antibody probes (e.g., anti-nucleolin and anti-fibrillarin). We describe here a sensitive fluorescent staining technique that uses avidin and propidium iodide to visualize the rDNA in the amplified nucleoli. Many large nucleoli stain about as brightly as haploid yeast nuclei on the same slides. They presumably contain about 12 Mb of DNA, equivalent to 900 rDNA repeats. The smallest micronucleoli display only a tiny dot of stain, which must correspond to relatively few rDNA repeats.
Birnstiel,
Properties and composition of the isolated ribosomal DNA satellite of Xenopus laevis.
1968, Pubmed,
Xenbase
Birnstiel,
Properties and composition of the isolated ribosomal DNA satellite of Xenopus laevis.
1968,
Pubmed
,
Xenbase
Brown,
Specific gene amplification in oocytes. Oocyte nuclei contain extrachromosomal replicas of the genes for ribosomal RNA.
1968,
Pubmed
Brown,
Gene linkage by RNA-DNA hybridization. I. Unique DNA sequences homologous to 4 s RNA, 5 s RNA and ribosomal RNA.
1968,
Pubmed
,
Xenbase
Buongiorno-Nardelli,
Electron microscope analysis of amplifying ribosomal DNA from Xenopus laevis.
1976,
Pubmed
,
Xenbase
Dumont,
Oogenesis in Xenopus laevis (Daudin). I. Stages of oocyte development in laboratory maintained animals.
1972,
Pubmed
,
Xenbase
Gall,
Differential synthesis of the genes for ribosomal RNA during amphibian oögenesis.
1968,
Pubmed
Heine,
The Gly/Arg-rich (GAR) domain of Xenopus nucleolin facilitates in vitro nucleic acid binding and in vivo nucleolar localization.
1993,
Pubmed
,
Xenbase
Hourcade,
The amplification of ribosomal RNA genes involves a rolling circle intermediate.
1973,
Pubmed
,
Xenbase
Hultman,
Selective induction of anti-fibrillarin autoantibodies by silver nitrate in mice.
1994,
Pubmed
Lerner,
Monoclonal antibodies to nucleic acid-containing cellular constituents: probes for molecular biology and autoimmune disease.
1981,
Pubmed
,
Xenbase
Macgregor,
The nucleolus and its genes in amphibian oogenesis.
1972,
Pubmed
,
Xenbase
Miller,
Structure and composition of peripheral nucleoli of salamander oocytes.
1966,
Pubmed
Painter,
Nucleic Acid Storage in the Toad's Egg.
1942,
Pubmed
Perkowska,
Gene amplification in the oocyte nucleus of mutant and wild-type Xenopus laevis.
1968,
Pubmed
,
Xenbase
RITOSSA,
LOCALIZATION OF DNA COMPLEMENTARY TO RIBOSOMAL RNA IN THE NUCLEOLUS ORGANIZER REGION OF DROSOPHILA MELANOGASTER.
1965,
Pubmed
Shah,
Structural changes in oocyte nucleoli of Xenopus laevis during oogenesis and meiotic maturation.
1996,
Pubmed
,
Xenbase
Wallace,
Ribosomal cistrons and the nucleolar organizer.
1966,
Pubmed
Wallace,
Protein incorporation by isolated amphibian oocytes. 3. Optimum incubation conditions.
1973,
Pubmed
,
Xenbase
Wellauer,
The molecular basis for length heterogeneity in ribosomal DNA from Xenopus laevis.
1976,
Pubmed
,
Xenbase
Wellauer,
Arrangement of length heterogeneity in repeating units of amplified and chromosomal ribosomal DNA from Xenopus laevis.
1976,
Pubmed
,
Xenbase
Wu,
Small nuclear ribonucleoproteins and heterogeneous nuclear ribonucleoproteins in the amphibian germinal vesicle: loops, spheres, and snurposomes.
1991,
Pubmed
,
Xenbase
Wu,
Snurposomes and coiled bodies.
1993,
Pubmed
,
Xenbase
Wu,
Human p80-coilin is targeted to sphere organelles in the amphibian germinal vesicle.
1994,
Pubmed
,
Xenbase
