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Updated: Jul 20, 2026
06:48
CD Spectroscopy to Study DNA-Protein Interactions
Published on: February 10, 2022
Activation-induced cytidine deaminase: structure-function relationship as based on the study of mutants
Anne Durandy1, Sophie Peron, Nadine Taubenheim
1Institut National de la Santé et de la Recherche Médicale (INSERM), U768, Hôpital Necker-Enfants Malades, Paris, France. durandy@necker.fr
Human Mutation
|September 12, 2006
Summary
Activation-induced cytidine deaminase (AID) is crucial for antibody diversification through class switch recombination and somatic hypermutation. AID functions as both an enzyme and a docking protein, recruiting cofactors for these essential immune processes.
Area of Science:
- Immunology
- Molecular Biology
- Genetics
Background:
- Activation-induced cytidine deaminase (AID) is essential for immunoglobulin gene diversification.
- AID deficiency leads to hyper-IgM (HIGM) syndrome, highlighting its critical role.
- Understanding AID's function is key to comprehending adaptive immunity.
Purpose of the Study:
- To characterize the functional domains of Activation-induced cytidine deaminase (AID).
- To elucidate the dual role of AID in immunoglobulin class switch recombination (CSR) and somatic hypermutation (SHM).
- To investigate the molecular mechanisms underlying AID's enzymatic and scaffolding functions.
Main Methods:
- Analysis of natural and engineered Activation-induced cytidine deaminase (AID) mutants.
- Biochemical assays to assess cytidine deaminase activity.
- Functional studies investigating cofactor recruitment in class switch recombination (CSR) and somatic hypermutation (SHM).
Main Results:
- AID's cytidine deaminase activity is essential for initiating DNA lesions in CSR and SHM.
- The C-terminus of AID is implicated in recruiting CSR-specific cofactors.
- The N-terminus of AID may bind SHM-specific cofactors, suggesting distinct functional domains.
- AID functions as a homo-, di-, or multimeric complex.
Conclusions:
- Activation-induced cytidine deaminase (AID) acts as a master regulator of antibody diversification.
- AID functions not only as an enzyme but also as a docking protein, recruiting specific cofactors.
- AID's multimeric complex formation is critical for its diverse roles in immune gene diversification.
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