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Updated: Aug 11, 2026
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Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation
Published on: March 5, 2018
Pro-EMAP II is not primarily cleaved by caspase-3 and -7
1Departments of Pediatrics, Cardiothoracic Surgical Research, and Surgery, Childrens Hospital Research Institute, Los Angeles 90027, USA.
Summary
The active form of Endothelial Monocyte-Activating Polypeptide II (EMAP II) has antiangiogenic properties. This study found that caspase-3 or -7 do not release active EMAP II, suggesting other enzymes are involved.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Endothelial monocyte-activating polypeptide II (EMAP II), also known as p43, is a cytokine with known antiangiogenic properties.
- The precise mechanism and enzymes responsible for releasing the active mature form of EMAP II from its precursor remain largely uncharacterized.
Purpose of the Study:
- To investigate the proteolytic enzymes involved in the cleavage and release of active mature EMAP II.
- To determine if caspase-3 or caspase-7 are responsible for processing pro-EMAP II.
Main Methods:
- In vitro cleavage assays using purified pro-EMAP II.
- In vivo studies to assess caspase-3 and caspase-7 activity in relation to EMAP II processing.
Main Results:
- Purified pro-EMAP II was not cleaved by either caspase-3 or caspase-7, contrary to previous assumptions.
- The findings indicate that caspase-3 and caspase-7 are not the primary enzymes responsible for releasing active EMAP II.
Conclusions:
- The release of active EMAP II, which induces apoptosis in endothelial cells, likely involves proteolytic pathways distinct from caspase-3 and caspase-7.
- Further research is needed to identify the specific proteases responsible for EMAP II maturation and its antiangiogenic function.
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