Cell cycle control by the Myc/Max/Mad network: Regulation of Mad by cyclin E/CDK2 and identification and characterization of Mad1 target genes Zellzyklusregulation durch das Myc/Max/Mad Netzwerk: Regulation von Mad durch Cyclin E/CDK2 und Identifizierung

Myc/Max/Mad网络的蛋白质在细胞生长、分化和凋亡的调节中起关键作用。Myc/Max/Mad复合物是序列特异性的DNA结合蛋白，作为转录调节因子发挥作用。虽然Myc的功能及其调控的基本方面是了解的，但还不清楚Mad 1蛋白是否受任何信号转导的调控，以及哪些是靶基因。由于我们已经发现，细胞周期蛋白E/CDK 2激酶复合物干扰Mad 1抑制细胞周期进程，我们建议研究这种激酶如何影响Mad 1功能。特别是，我们将询问是否细胞周期蛋白E/CDK 2可以调节Mad 1-阻遏复合物。第二个目的是使用体内交联方法鉴定Mad 1靶基因。这将使我们能够识别Mad 1蛋白的体内结合位点，并克隆相应的DNA。这些DNA片段可用于鉴定相关基因，然后将特别强调编码蛋白在Mad 1介导的S期进展抑制中的作用。

The proteins of the Myc/Max/Mad network play pivotal roles in the regulation of cell growth, differentiation and apoptosis. Myc/Max/Mad complexes are sequence-specific DNA binding proteins that function as transcriptional regulators. While the basic aspects of the function of Myc and its regulation are understood, it is not clear whether Mad1 proteins are regulated by any signaling and which are the target genes. Since we have found that the cyclin E/CDK2 kinase complex interferes with Mad1 inhibition of cell cycle progression we propose to study how this kinase affects Mad1 function. In particular we will ask whether cyclin E/CDK2 can modulate the Mad1-repressor complex. The second aim is to identify Mad1 target genes using an in vivo cross-linking approach. This will allow us to identify in vivo binding sites for Mad1 proteins and to clone the corresponding DNA. These DNA fragments can be used to identify associated genes which will then be characterized with a particular emphasis on the role of the encoded proteins in Mad1mediated inhibition of S phase progression.