Molecular Studies on Antigen Receptor Gene Recombination

阿奎莱拉9603905 一种被认为参与免疫球蛋白同种型-类别转换重组的淋巴细胞特异性过程的酶已被鉴定并部分纯化。该酶优先切割通常在开关重组断点处发现的tgggg和tggl开关重复基序。从小鼠B淋巴细胞和牛脾细胞的核提取物中纯化出的酶活性接近均一。纯化的酶，现在称为endo-sr的初步生化表征，支持最初的假设，酶是新的。将继续进行生物化学表征，以寻找数据来验证该酶是推定的开关核酸内切酶活性的假设。为此，将根据通过确定纯化酶的肽组成获得的信息开始克隆基因的工作。 对淋巴细胞中涉及体细胞DNA重排的各种因素（包括所涉及的酶）的进一步表征，不仅可以更好地理解IG开关重组过程，还可以更好地理解哺乳动物细胞中体细胞DNA重组的潜在机制。

Aguilera 9603905 An enzyme which is thought to be involved in the lymphocyte-specific process of immunoglobulin isotype-class switch recombination has been identified and partially purified. The enzyme preferentially cleaves tgggg and tgagc switch repeat motifs commonly found at switch recombination breakpoints. The enzyme activity has been purified to near homogeneity from nuclear extracts of murine b lymphocytes and bovine splenocytes. Preliminary biochemical characterization with the purified enzyme, now called endo-sr, support the initial assumption that the enzyme is novel. The biochemical characterization will be continued in the search for data to validate the hypothesis that this enzyme is a putative switch endonuclease activity. To that end, work will be initiated to clone the gene based upon the information gained by determining the peptide composition of the purified enzyme. Further characterization of the various factors, including the involved enzyme(s), implicated in somatic DNA rearrangements in lymphocytes should lead to a better understanding of not only the ig switch recombination process but also the underlying mechanisms of somatic DNA recombination in mammalian cells.