Immunoglobulin Genes: Generating Diversity with AID and UNG
نویسندگان
چکیده
Somatic hypermutation and switch recombination of immunoglobulin genes require the activity of the activation-induced deaminase, AID. Recent studies of mice deficient for the uracil-DNA glycosylase UNG, which removes U from DNA, suggest that AID catalyses the deamination of dC to dU during antibody diversification.
منابع مشابه
UNG shapes the specificity of AID-induced somatic hypermutation
Secondary diversification of antibodies through somatic hypermutation (SHM) and class switch recombination (CSR) is a critical component of the immune response. Activation-induced deaminase (AID) initiates both processes by deaminating cytosine residues in immunoglobulin genes. The resulting U:G mismatch can be processed by alternative pathways to give rise to a mutation (SHM) or a DNA double-s...
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Activation-induced cytidine deaminase (AID) is required for the DNA cleavage step in immunoglobulin class switch recombination (CSR). AID is proposed to deaminate cytosine to generate uracil (U) in either mRNA or DNA. In the second instance, DNA cleavage depends on uracil DNA glycosylase (UNG) for removal of U. Using phosphorylated histone gamma-H2AX focus formation as a marker of DNA cleavage,...
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عنوان ژورنال:
- Current Biology
دوره 12 شماره
صفحات -
تاریخ انتشار 2002