Relationship between organization and function of ribosomal genes in Drosophila melanogaster

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 1987

OSTI ID:5990375

Karpen, G H

In most eukaryotic organisms, the genes that encode the 18S and 28S ribosomal RNAs (rDNA genes) are tandemly repeated, and are located in constitutive heterochromatin and/or centromeric or telomeric regions. P-element mediated transformation was used to investigate the relationship between rDNA organization and function in Drosophila melanogaster. Tritiated-uridine incorporation under heat shock conditions and in situ hybridization to rRNA were used to demonstrate that a single rDNA gene inserted into euchromatin can be transcribed at a high rate, in polytene nuclei. P-element-mediated transformation of a single Drosophila rDNA gene was also utilized to investigate the ability of ribosomal DNA to organize a nucleolus. Cytological approaches demonstrated that structures resembling the endogenous nucleoli were preferentially associated with four different sites of rDNA insertion, in polytene nuclei. These mini-nucleoli also contained components specific to the nucleolus, as shown by in situ hybridization to rRNA and indirect immunofluorescence with an antibody that binds to Drosophila nucleoli. The transformed genes were able to partially rescue mutant phenotypes due to a deficiency of rDNA, indicating that the mini-nucleoli were functional.

• Research Organization: Washington Univ., Seattle (USA)
• OSTI ID: 5990375
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
DNA
HYBRIDIZATION
DROSOPHILA
GENE RECOMBINATION
GENES
BIOLOGICAL FUNCTIONS
RIBOSOMAL RNA
CELL NUCLEI
TRACER TECHNIQUES
TRANSCRIPTION
TRITIUM COMPOUNDS
ANIMALS
ARTHROPODS
CELL CONSTITUENTS
DIPTERA
FLIES
FRUIT FLIES
FUNCTIONS
INSECTS
INVERTEBRATES
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
RNA
550201* - Biochemistry- Tracer Techniques