PMID: 8955393Dec 1, 1996Paper

Long-distance effect of downstream transcription on activity of the supercoiling-sensitive leu-500 promoter in a topA mutant of Salmonella typhimurium

Journal of Bacteriology
F Spirito, L Bossi

Abstract

Expression of the lacZ gene from the supercoiling-sensitive leu-500 promoter on a plasmid in topA mutant cells was stimulated by activating a divergently oriented Tac promoter, 400 bp upstream from leu-500. The stimulation was approximately threefold regardless of whether the Tac promoter drove the expression of the tet gene, whose product is membrane bound, or of the cat gene, whose product is cytosolic. Putting a second copy of the Tac promoter downstream from lacZ, approximately 3,000 bp from leu-500 in the same orientation as the latter, resulted in 30-fold increase in lacZ expression upon isopropyl-beta-D-thiogalactopyranoside induction. Again, these effects were independent of the nature of the gene upstream from leu-500 (tet or cat). With both tet- and cat-harboring constructs, activation of the two Tac promoter copies caused plasmid DNA to become hypernegatively supercoiled in topA mutant cells. Thus, neither leu-500 activation nor hypernegative plasmid DNA supercoiling appears to require membrane anchoring of DNA in this system. Replacing the downstream copy of Tac with a constitutive promoter resulted in high-level lacZ expression even when the upstream copy was repressed. Under these conditions, no hypernegative DNA ...Continue Reading

References

Sep 15, 1992·Proceedings of the National Academy of Sciences of the United States of America·D ChenD M Lilley
Dec 20, 1992·Journal of Molecular Biology·H Y WuL F Liu
Nov 25, 1992·Nucleic Acids Research·A DaynS M Mirkin
Jan 1, 1991·Methods in Enzymology·N KlecknerS Gottesman
Jan 5, 1992·Journal of Molecular Biology·A R Rahmouni, R D Wells
Jun 20, 1991·Journal of Molecular Biology·H Y Wu, L F Liu
Dec 1, 1989·Journal of Bacteriology·R J Franco, K Drlica
Apr 1, 1989·Journal of Bacteriology·J K LodgeD E Berg
Oct 20, 1989·Science·A R Rahmouni, R D Wells
Oct 1, 1987·Proceedings of the National Academy of Sciences of the United States of America·L F Liu, J C Wang
Dec 1, 1988·Proceedings of the National Academy of Sciences of the United States of America·N Figueroa, L Bossi
Aug 1, 1985·Proceedings of the National Academy of Sciences of the United States of America·P MargolinJ C Wang
Dec 1, 1986·Proceedings of the National Academy of Sciences of the United States of America·G J Pruss, K Drlica
Feb 1, 1994·Journal of Bacteriology·J TanH Y Wu

❮ Previous
Next ❯

Citations

Feb 11, 1998·Journal of Bacteriology·M Fang, H Y Wu
Sep 16, 2008·Journal of Bacteriology·Imad BaakliniMarc Drolet
Mar 27, 1999·Journal of Bacteriology·C DelormeP Renault
Oct 8, 1999·Journal of Molecular Biology·A S KrasilnikovS M Mirkin
Nov 26, 1997·Journal of Bacteriology·S Brantl, E G Wagner

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.