alexa Characterization of IFN-gamma regulation of the complement factor B gene in macrophages.
Ophthalmology

Ophthalmology

Journal of Clinical & Experimental Ophthalmology

Author(s): Huang Y, Krein PM, Winston BW

Abstract Share this page

Abstract Complement factor B (Bf) is involved in the activation of the alternative complement cascade. Bf is induced by IFN-gamma; however, the mechanisms of Bf gene regulation have not been well characterized in general, and not in macrophages specifically. Northern analysis reveals that IFN-gamma induces a dose- and time-dependent increase in Bf mRNA expression in primary macrophages and macrophage cell lines. MH-S cells transfected with reporter constructs containing truncated regions of the Bf promoter reveal that IFN-gamma responsiveness lies between -154 and -53 bp on the Bf promoter. This region of the Bf promoter contains both an IFN-gamma-activation site (GAS) and an interferon-stimulated response element (ISRE). Site-directed mutagenesis of the GAS binding site or the ISRE binding site in this region of the Bf promoter partially inhibits IFN-gamma responsiveness. Mutagenesis of both the GAS and ISRE cis elements totally abrogates IFN-gamma responsiveness of the Bf promoter. Electrophoretic mobility shift assays reveal nuclear binding complexes involving both Bf-GAS and Bf-ISRE oligonucleotide sequences upon IFN-gamma stimulation. In competition assays, both Bf-GAS and Bf-ISRE oligonucleotides, but not mutant Bf-GAS nor mutant Bf-ISRE oligonucleotides, compete for the DNA binding. Supershift analysis reveals that Stat1-GAS and IRF-1-ISRE nuclear binding complexes contribute to induction of Bf by IFN-gamma. Western analysis confirms an IFN-gamma-stimulated increase in tyrosine phosphorylation of Stat1. These findings suggest that both GAS and ISRE cis binding sites have an additive effect on IFN-gamma-stimulated Bf gene expression and that both are required for full expression of Bf by IFN-gamma. Stat1 and IRF-1 take part in IFN-gamma-stimulated Bf gene induction in macrophages through their respective cis binding elements.
This article was published in Eur J Immunol and referenced in Journal of Clinical & Experimental Ophthalmology

Relevant Expert PPTs

Relevant Speaker PPTs

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri, Food, Aqua and Veterinary Science Journals

Dr. Krish

[email protected]

1-702-714-7001 Extn: 9040

Clinical and Biochemistry Journals

Datta A

[email protected]

1-702-714-7001Extn: 9037

Business & Management Journals

Ronald

[email protected]

1-702-714-7001Extn: 9042

Chemical Engineering and Chemistry Journals

Gabriel Shaw

[email protected]

1-702-714-7001 Extn: 9040

Earth & Environmental Sciences

Katie Wilson

[email protected]

1-702-714-7001Extn: 9042

Engineering Journals

James Franklin

[email protected]

1-702-714-7001Extn: 9042

General Science and Health care Journals

Andrea Jason

[email protected]

1-702-714-7001Extn: 9043

Genetics and Molecular Biology Journals

Anna Melissa

[email protected]

1-702-714-7001 Extn: 9006

Immunology & Microbiology Journals

David Gorantl

[email protected]

1-702-714-7001Extn: 9014

Informatics Journals

Stephanie Skinner

[email protected]

1-702-714-7001Extn: 9039

Material Sciences Journals

Rachle Green

[email protected]

1-702-714-7001Extn: 9039

Mathematics and Physics Journals

Jim Willison

[email protected]

1-702-714-7001 Extn: 9042

Medical Journals

Nimmi Anna

[email protected]

1-702-714-7001 Extn: 9038

Neuroscience & Psychology Journals

Nathan T

[email protected]

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

John Behannon

[email protected]

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

[email protected]

1-702-714-7001 Extn: 9042

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords