MECHANISMS OF P53 MEDIATED APOPTOSIS AND CARCINOGENESIS

作为了解p53介导的细胞凋亡机制的一步， 细胞凋亡和致癌作用，我们已经确定了一个新的推定锌 手指转录因子，Pw 1/ASF-1，和两个CED 3/ICE相关 蛋白酶，NEDD 2和CPP 32，其基因表达被诱导 特别是在p53介导的凋亡过程中。 这个的主要目标 研究项目是调查这三个的作用和调节 p53介导的凋亡中的基因产物。 在第一个具体目标中， Pw 1/ASF-1诱导在p53介导的细胞凋亡中的意义 将检测细胞凋亡。 该蛋白的生物学功能将是 通过在哺乳动物中表达Pw/ASF-1基因产物进行分析 细胞 Pw 1/ASF-1蛋白如何作为转录因子发挥作用 将在具体目标2中探讨。 鉴定DNA的实验 提出了通过体外免疫选择方法的结合位点。 Pw 1/ASF-1基因表达的调控机制也将在本研究中进行探讨。 通过分析其启动子和增强子元件进行研究。 在 第三个具体目标，CED 3/ICE相关蛋白酶NEDD 2的调节 和CPP 32在p53介导的细胞凋亡过程中的作用。 的 假设蛋白酶基因表达诱导可以作为 将测试激活CED 3/ICE相关蛋白酶的机制。 p53基因的改变经常与人类癌症有关 而p53介导的凋亡在防止 致癌和恶性肿瘤，因此，了解机制 p53诱导的细胞凋亡是一个重要的研究方向， 可能为更好地治疗人类肿瘤提供依据。

As a step toward understanding the mechanisms of p53 mediated apoptosis and carcinogenesis, we have identified a new putative zinc finger transcription factor, Pw1/ASF-1, and two CED3/ICE-related proteases, NEDD2 and CPP32, whose gene expressions are induced specifically during p53 mediated apoptosis. The main goal of this research project is to investigate the role and regulation of these three gene products in p53-mediated apoptosis. In the first specific aim, significance of the induction of Pw1/ASF-1 during p53 mediated apoptosis will be examined. Biological functions of this protein will be analyzed by expressing the Pw/ASF-1 gene product in mammalian cells. How the Pw1/ASF-1 protein functions as a transcription factor will be explored in specific aim 2. Experiments to identify the DNA binding sites by an in vitro immuno-selection method are proposed. Regulatory mechanism of the Pw1/ASF-1 gene expression will also be investigated by analyzing its promoter and enhancer elements. In the third specific aim, regulation of CED3/ICE related proteases, NEDD2 and CPP32, during p53 mediated apoptosis will be examined. The hypothesis that Induction of protease gene expression can serve as a mechanism to activate CED3/ICE related proteases will be tested. Genetic alteration of p53 is frequently associated with human cancers and p53-mediated apoptosis plays a critical role to prevent carcinogenesis and malignancies, Thus, understanding the mechanism of p53-induced apoptosis represents an important research avenue and may provide a basis for better treatment of human tumors.