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Updated: Jun 15, 2026
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Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation
Published on: March 5, 2018
Structure, expression and function of Allomyces arbuscula CDP II (metacaspase) gene
Mukti Ojha1, Arlette Cattaneo, Séverine Hugh
1Department of Biochemistry, University of Geneva, Sciences II, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland. Mukti.Ojha@unige.ch
Gene
|March 11, 2010
Summary
Allomyces metacaspase 2 (AMca 2), a calcium-dependent cysteine protease, promotes fungal growth. Its activity is regulated by specific amino acid sequences and calcium ions, and it is inhibited by certain protease inhibitors.
Area of Science:
- Mycology
- Biochemistry
- Molecular Biology
Background:
- Allomyces arbuscula possesses two calcium-dependent cysteine proteases (CDP I and CDP II).
- CDP II has been identified as a metacaspase, a novel member of the caspase superfamily.
Purpose of the Study:
- To clone and analyze the CDP II gene and protein structure.
- To characterize the enzymatic properties and regulation of AMca 2.
Main Methods:
- Gene cloning and nucleotide sequencing
- Blast analysis
- Southern and Northern hybridization
- Recombinant protein expression and characterization
- Enzyme kinetics and inhibitor studies
Main Results:
- The CDP II gene was cloned and sequenced, revealing AMca 2 belongs to the metacaspase family.
- AMca 2 is developmentally regulated, present during active growth and absent during nutritional stress.
- Recombinant AMca 2 exhibits calcium-dependent catalytic activity with specific substrate requirements (R at P1, P/G at P2).
- Enzyme activity is inhibited by EDTA-EGTA, cysteine protease inhibitors, and a specific peptide inhibitor, but not E64.
Conclusions:
- AMca 2 is a calcium-dependent cysteine protease that promotes cell growth in Allomyces arbuscula.
- Its activity is modulated by substrate sequence and calcium, and it represents a new class of metacaspases.
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