Coker Heather A, Morgan Hugh D, Petersen-Mahrt Svend K
DNA Editing Laboratory, Cancer Research United Kingdom, Clare Hall Laboratories, South Mimms, Hertfordshire.
Methods Enzymol. 2006;408:156-70. doi: 10.1016/S0076-6879(06)08010-4.
The DNA deaminase family encompasses enzymes that have been highly conserved throughout vertebrate evolution and which display wide-ranging positive effects upon innate and adaptive immune system and development. Activation-induced cytidine deaminase was identified as a DNA mutator after its necessity in the successful development of high-affinity B cells via somatic hypermutation, class switch recombination, and gene conversion was determined. APOBEC3 exhibits the ability to deaminate retroviral first strand cDNA in a variety of viral infections, including HIV and hepatitis. Recent work has highlighted the potential importance of activation-induced cytidine deaminase (AID) and APOBEC1 in epigenetic reprogramming, and also the role that AID and the APOBECs may have in the development of cancer. In addition to the known activities of these members of the protein family, there are still other deaminases, such as APOBEC2, whose targets and functions are as yet unknown. This chapter provides the details of two assays that have proved to be invaluable in elucidating the exact specificities of deaminases both in vitro and in Escherichia coli. The application of these assays to future studies of the deaminase family will provide an indispensible tool in determining the potentially diverse functions of the remainder of this family of enzymes.
DNA脱氨酶家族包含在整个脊椎动物进化过程中高度保守的酶，这些酶对先天免疫系统、适应性免疫系统及发育具有广泛的积极作用。活化诱导的胞嘧啶脱氨酶在通过体细胞高频突变、类别转换重组和基因转换成功发育高亲和力B细胞的过程中被确定为一种DNA诱变剂。在包括HIV和肝炎在内的多种病毒感染中，载脂蛋白B mRNA编辑酶催化多肽样3（APOBEC3）表现出对逆转录病毒第一链cDNA进行脱氨基的能力。最近的研究突出了活化诱导的胞嘧啶脱氨酶（AID）和载脂蛋白B mRNA编辑酶催化多肽样1（APOBEC1）在表观遗传重编程中的潜在重要性，以及AID和APOBECs在癌症发生发展中可能发挥的作用。除了该蛋白质家族这些成员的已知活性外，还有其他脱氨酶，如APOBEC2，其作用靶点和功能尚不清楚。本章详细介绍了两种检测方法，事实证明这两种方法在阐明脱氨酶在体外和大肠杆菌中的确切特异性方面非常宝贵。将这些检测方法应用于脱氨酶家族的未来研究，将为确定该酶家族其余成员的潜在多样功能提供不可或缺的工具。
