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Native Polyacrylamide Gel Electrophoresis Immunoblot Analysis of Endogenous IRF5 Dimerization
Published on: October 6, 2019
IRF5 is required for late-phase TNF secretion by human dendritic cells
Thomas Krausgruber1, David Saliba, Grigory Ryzhakov
1Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College of Science, Technology and Medicine, London, United Kingdom.
Blood
|March 19, 2010
Summary
Interferon regulatory factor 5 (IRF5) controls late-phase tumor necrosis factor (TNF) secretion in dendritic cells (DCs), crucial for T-cell activation. IRF5 interacts with NF-kappaB RelA for TNF gene regulation.
Area of Science:
- Immunology
- Molecular Biology
- Cell Biology
Background:
- Controlled expression of inflammatory mediators is vital for effective immune responses.
- Tumor necrosis factor (TNF) plays a key role in T-cell activation by dendritic cells (DCs).
Purpose of the Study:
- To elucidate the role of interferon regulatory factor 5 (IRF5) in regulating TNF secretion by human DCs.
- To investigate the molecular mechanisms by which IRF5 controls TNF gene expression.
Main Methods:
- Bioinformatic and biochemical analyses of the TNF gene locus.
- Assessment of IRF5 protein levels in dendritic cells and macrophages.
- Investigation of IRF5 recruitment to the TNF gene promoter and downstream regions.
Main Results:
- Dendritic cells (DCs) express high levels of IRF5 protein, unlike macrophages.
- IRF5 is essential for the late-phase expression of TNF in DCs.
- IRF5 binds to the upstream region of the TNF gene and interacts with NF-kappaB RelA for recruitment to the downstream region.
Conclusions:
- IRF5 plays a critical role in sustained TNF secretion by DCs, which is essential for T-cell activation.
- IRF5 employs diverse mechanisms to regulate gene expression, including direct DNA binding and protein-protein interactions.
- The interaction between RelA and IRF5 presents a potential target for modulating TNF expression in a cell-specific manner.
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