Biomaterial Database

The 5'-flanking sequences of Drosophila melanogaster tRNA5Asn genes differentially arrest RNA polymerase III. 1986

A Lofquist, and S Sharp

Three tRNA5Asn genes have been subcloned from a tRNA gene cluster isolated from the cytogenetic locus 42A of Drosophila melanogaster. The three tRNAAsn genes, contained on plasmids pAsn6, pAsn7, and pAsn8, have identical mature tRNA coding regions but have different 5'- and 3'-flanking sequences. In vitro transcription in Drosophila Schneider S3 cell-free extracts showed the tRNAAsn genes had different transcription efficiencies. pAsn8 had a transcription efficiency of approximately 8 transcripts/gene/h, whereas pAsn6 was a less active template at 5 transcripts/gene/h. pAsn7 was the poorest template at 1.5 transcripts/gene/h. Exchanging 5'-flanking regions of the tRNAAsn genes showed that the differences in transcription efficiencies were attributable to the corresponding 5'-flanking region. Transcription of each of the tRNAAsn genes revealed a different optimum for KC1 concentration for each template which also was directly attributable to the corresponding 5'-flanking region. The "salt effect" is not related to the ability of the three tRNAAsn genes to sequester transcription factors as determined using the stable complex competition assay. Rather, this effect appears to be due to the ability of the respective 5'-flanking regions to interact with RNA polymerase III. The poorest transcription template, pAsn7, was a better competitor in the stable complex formation assay than either pAsn8 or pAsn6. We conclude that the pAsn7 stable complex binds and functionally arrests RNA polymerase III in the initiation reaction.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010957	Plasmids	Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.	Episomes,Episome,Plasmid
D003001	Cloning, Molecular	The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.	Molecular Cloning
D004331	Drosophila melanogaster	A species of fruit fly frequently used in genetics because of the large size of its chromosomes.	D. melanogaster,Drosophila melanogasters,melanogaster, Drosophila
D005796	Genes	A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.	Cistron,Gene,Genetic Materials,Cistrons,Genetic Material,Material, Genetic,Materials, Genetic
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001226	Aspartate-tRNA Ligase	An enzyme that activates aspartic acid with its specific transfer RNA. EC 6.1.1.12.	Aspartyl T RNA Synthetase,Asp-tRNA Ligase,Aspartyl-tRNA Synthetase,Asp tRNA Ligase,Aspartate tRNA Ligase,Aspartyl tRNA Synthetase,Ligase, Asp-tRNA,Ligase, Aspartate-tRNA,Synthetase, Aspartyl-tRNA
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D012320	RNA Polymerase III	A DNA-dependent RNA polymerase present in bacterial, plant, and animal cells. It functions in the nucleoplasmic structure where it transcribes DNA into RNA. It has specific requirements for cations and salt and has shown an intermediate sensitivity to alpha-amanitin in comparison to RNA polymerase I and II.	DNA-Dependent RNA Polymerase III,RNA Polymerase C,DNA Dependent RNA Polymerase III,Polymerase C, RNA,Polymerase III, RNA
D012321	DNA-Directed RNA Polymerases	Enzymes that catalyze DNA template-directed extension of the 3'-end of an RNA strand one nucleotide at a time. They can initiate a chain de novo. In eukaryotes, three forms of the enzyme have been distinguished on the basis of sensitivity to alpha-amanitin, and the type of RNA synthesized. (From Enzyme Nomenclature, 1992).	DNA-Dependent RNA Polymerases,RNA Polymerases,Transcriptases,DNA-Directed RNA Polymerase,RNA Polymerase,Transcriptase,DNA Dependent RNA Polymerases,DNA Directed RNA Polymerase,DNA Directed RNA Polymerases,Polymerase, DNA-Directed RNA,Polymerase, RNA,Polymerases, DNA-Dependent RNA,Polymerases, DNA-Directed RNA,Polymerases, RNA,RNA Polymerase, DNA-Directed,RNA Polymerases, DNA-Dependent,RNA Polymerases, DNA-Directed