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Updated: Feb 21, 2026
08:55
Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag
Published on: December 14, 2017
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PKC-dependent phosphorylation of Munc18a at Ser313 in activated RBL-2H3 cells.
1Department of Biological Sciences, University of Southern Mississippi, 118 College Drive, #5018, Hattiesburg, MS, 39406, USA.
Summary
Protein Kinase C (PKC) regulates mast cell degranulation. This study reveals PKC inhibition prevents Munc18a phosphorylation, suggesting a direct role in membrane fusion during inflammatory responses.
Area of Science:
- Immunology
- Cell Biology
- Biochemistry
Background:
- Mast cells release inflammatory compounds upon IgE/antigen activation.
- Protein Kinase C (PKC) is implicated in regulating this process.
- The precise mechanisms by which PKC controls mast cell degranulation remain unclear.
Purpose of the Study:
- To elucidate the role of PKC in mast cell degranulation.
- To investigate the molecular targets of PKC in this cellular process.
- To determine if PKC directly influences membrane fusion machinery.
Main Methods:
- Utilized the RBL-2H3 mast cell line.
- Administered PKC inhibitor Ro-03-0432.
- Assessed exocytosis/degranulation.
- Analyzed Munc18a phosphorylation at Ser 313.
Main Results:
- PKC inhibitor Ro-03-0432 demonstrated a concentration-dependent inhibition of RBL-2H3 cell exocytosis/degranulation.
- The inhibitor prevented the phosphorylation of the membrane fusion factor Munc18a at the Ser 313 site.
- This indicates a direct link between PKC activity and the regulation of key fusion proteins.
Conclusions:
- PKC plays a significant role in regulating mast cell degranulation.
- PKC-dependent phosphorylation of Munc18a is a key mechanism in controlling membrane fusion.
- These findings offer novel insights into the molecular pathways governing inflammatory mediator release from mast cells.
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