Related Experiment Video
Updated: Jan 8, 2026
11:31
Isolation of Peritoneum-derived Mast Cells and Their Functional Characterization with Ca2+-imaging and Degranulation Assays
Published on: July 4, 2018
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Serous Cavity Mast Cells Depend on the ROQUIN Paralogs
Klaus Heger1,2,3, Ali Masjedi1,4, Assa Yeroslaviz2
1Institute of Experimental Hematology, School of Medicine and Health, Technical University of Munich, Munich, Germany.
European Journal of Immunology
|December 19, 2025
Summary
ROQUIN-1 and ROQUIN-2 proteins are crucial for serosal mast cells but not skin mast cells. These RNA-binding proteins regulate specific messenger RNAs in mast cells, impacting immune responses.
Area of Science:
- Immunology
- Molecular Biology
- Cell Biology
Background:
- Mast cells are key immune sentinels at pathogen entry points.
- ROQUIN proteins (ROQUIN-1 and ROQUIN-2) regulate T cell activation.
- Antigen receptor engagement triggers mast cell degranulation and cytokine release.
Purpose of the Study:
- To investigate the function of ROQUIN-1 and ROQUIN-2 in connective tissue mast cells.
- To determine the role of ROQUIN proteins in mast cell development, maintenance, and activation.
Main Methods:
- Conditional gene knockout in mice to ablate ROQUIN-1 and ROQUIN-2 in mast cells.
- In vitro and in vivo experiments to assess mast cell degranulation and cytokine secretion.
- RNA sequencing to identify ROQUIN-regulated messenger RNAs in mast cells.
Main Results:
- ROQUIN-1 and ROQUIN-2 are dispensable for skin mast cell development and maintenance.
- These proteins are essential for serosal mast cells in the peritoneal and pleural cavities.
- Mast cell degranulation and secretion of TNF and IL-6 were unaffected by ROQUIN ablation.
- Identified Runx1t1, Ebi3, and Lfng as ROQUIN-regulated targets in mast cells.
Conclusions:
- ROQUIN proteins play an essential, cell-type-specific role in connective tissue mast cells within serosal cavities.
- ROQUIN's function in mast cells is distinct from its role in T cells, particularly regarding degranulation and cytokine secretion.
- This study elucidates novel targets and functions of ROQUIN in the immune system.
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