Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Competition between sigma factors for core RNA polymerase.

S Malik1, K Zalenskaya, A Goldfarb

  • 1Department of Microbiology, Columbia University College of Physicians and Surgeons, New York, NY 10032.

Nucleic Acids Research
|October 26, 1987
PubMed
Summary

Bacteriophage T4 uses sigma gp55 to switch RNA polymerase specificity, but host sigma 70 can displace it. This suggests T4 infection produces an antagonist to facilitate the switch.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

A Hebrew adaptation of the tinnitus functional index.

Clinical otolaryngology : official journal of ENT-UK ; official journal of Netherlands Society for Oto-Rhino-Laryngology & Cervico-Facial Surgery·2017
Same author

To proceed or not to proceed: ENT surgery in paediatric patients with acute upper respiratory tract infection.

The Journal of laryngology and otology·2016
Same author

The Impact of Partial Vascular Occlusion on Oxidative Stress Markers during Resistance Exercise.

International journal of sports medicine·2015
Same author

Severity of pneumococcal versus non-pneumococcal acute otitis media in children.

Clinical otolaryngology : official journal of ENT-UK ; official journal of Netherlands Society for Oto-Rhino-Laryngology & Cervico-Facial Surgery·2015
Same author

Oxidative stress and inflammation response following aerobic exercise: role of ethnicity.

International journal of sports medicine·2014
Same author

Current mental health program evaluation in San Mateo County.

Community mental health journal·2013

Area of Science:

  • Molecular Biology
  • Virology
  • Genetics

Background:

  • Bacteriophage T4 regulates gene expression by switching RNA polymerase specificity.
  • This switch involves replacing the host sigma 70 factor with the phage-induced sigma gp55.

Purpose of the Study:

  • To investigate the mechanism of sigma factor competition in bacteriophage T4 gene regulation.
  • To understand the interaction between sigma 70 and sigma gp55 with RNA polymerase.

Main Methods:

  • Direct competition binding assays were used to study the binding affinities of sigma 70 and sigma gp55 to RNA polymerase.
  • Experiments involved overproducing sigma gp55 in Escherichia coli and analyzing its effect on RNA polymerase activity.

Main Results:

Related Experiment Videos

  • Overproduction of sigma gp55 did not inhibit Escherichia coli growth.
  • Sigma 70 was found to readily displace sigma gp55 from RNA polymerase in binding assays.
  • This displacement reversed the promoter specificity of the RNA polymerase, an effect also observed with T4-infected core enzyme.

Conclusions:

  • Sigma 70 can actively compete with and displace sigma gp55 from the RNA polymerase core enzyme.
  • A mechanism involving an antagonist to sigma 70 is postulated to facilitate the early to late promoter switch in T4-infected cells.