Functions and interactions of the Rad6 pathway in vertebrates

在酵母复制过程中，Rad6上位基团通过诱变翻译聚合酶或基于重组的无错误修复模式控制DNA损伤的绕过。Rad6通路的成员在高等真核生物中是保守的，但其功能的确切保守程度迄今尚不清楚。靶向突变和重组在免疫系统中的抗体多样化中起着重要作用，但在这些过程中如何调节修复途径的决定和易出错聚合酶的募集尚不清楚。我们发现Rad6通路参与了鸡B细胞系DT40免疫球蛋白基因的体细胞超突变，提示该通路也控制着脊椎动物抗体多样化过程中突变与重组的决定。在本项目中，我们希望更详细地研究Rad6通路在脊椎动物细胞的一般和靶向同源重组和诱变过程中的功能。此外，我们希望利用亲和纯化来研究Rad6通路成员之间的相互作用以及与DNA修复和细胞周期控制的其他通路的相互作用。

The Rad6 epistasis group controls the bypass of DNA lesions during replication in yeast by either mutagenic translesion polymerases or by recombination based error free repair modes. Members of the Rad6 pathway are conserved in higher eukaryotes, but the exact degree of conservation of their function is unclear to date. Targeted mutagenesis and recombination play a major role in antibody diversification in the immune system, but it is unknown how repair pathway decision and recruitment of error-prone polymerases is regulated during these processes. We have found that the Rad6 pathway is involved in somatic hypermutation of immunoglobulin genes in the chicken B cell line DT40, suggesting that this pathway also controls the decision between mutagenesis and recombination during antibody diversification in vertebrates. In the present project, we wish to investigate in more detail the functions of the Rad6 pathway during general as well as targeted homologous recombination and mutagenesis in vertebrate cells. Also, we want to employ affinity purification to study the interactions of Rad6 pathway members with each other and with other pathways of DNA repair and cell cycle control.