Activation-induced cytidine deaminase (AID) is a key enzyme for antibody-mediated immune responses. Antibodies are encoded by the immunoglobulin genes and AID acts as a transcription-dependent DNA mutator on these genes to improve antibody affinity and effector functions. An emerging theme in field is that many transcribed genes are potential targets of AID, presenting an obvious danger to genomic integrity. Thus there are mechanisms in place to ensure that mutagenic outcomes of AID activity are specifically restricted to the immunoglobulin loci. Cis-regulatory targeting elements mediate this effect and their mode of action is probably a combination of immunoglobulin gene specific activation of AID and a perversion of faithful DNA repair towards error-prone outcomes.

中文翻译：

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AID 介导的序列多样化靶向免疫球蛋白基因。

激活诱导的胞苷脱氨酶 (AID) 是抗体介导的免疫反应的关键酶。抗体由免疫球蛋白基因编码，AID 在这些基因上充当转录依赖性 DNA 增变剂，以提高抗体亲和力和效应子功能。该领域的一个新兴主题是，许多转录基因是 AID 的潜在目标，对基因组完整性构成明显危险。因此，有一些机制可以确保 AID 活性的诱变结果特别限于免疫球蛋白基因座。顺式调节靶向元件介导了这种效应，它们的作用方式可能是免疫球蛋白基因特异性激活 AID 和忠实 DNA 修复向容易出错的结果的倒转的组合。