Identification of Alternative Hif-1a Dimerization artners in Arnt (Hifljff)-null

P53抑癌基因家族的成员(P53、P63和P73)在动物细胞功能中起关键作用。 发展和肿瘤抑制。特别是P63，已知对儿童的发展至关重要。 表皮。P63mRNAs可以通过两个启动子转录，产生不同的N末端， 确定它们是否包含(TA)或缺少(DN)完整激活域。TAp63是最近推出的 建议在胚胎发育过程中直接向角质形成细胞承诺，而DNp63是主要的异构体 在正常角质形成细胞和具有高增殖潜能的肿瘤角质形成细胞中均有发现。因为分子 P63功能的潜在机制在很大程度上仍不清楚，我们建议通过以下方式进行研究 接近了。 首先，我们使用人角质形成细胞cdna文库进行了详尽的酵母双杂交筛选。 并确定了4个新颖的P63互动伙伴。我们目前正在研究生物功能， 是由p63及其结合伙伴介导的。第二，P63与其家庭成员之间的相声 (P53和TAp63)将被调查。已发现角质形成细胞中主要的p63亚型DNp63， 在报告实验中可抑制P53和TAp63的活性。我们计划研究DNp63是否可以 抑制体内P53和TAp63的活性及其是否受p63-bining的调节 蛋白质。第三，我们将利用两条染色体在角质形成细胞中寻找与p63结合的直接靶基因。 免疫沉淀法和DNA微阵列分析。一旦这些基因被确定，p63是如何 (连同其结合蛋白)调节它们，以及它们在角质形成细胞中的作用将会是什么。 被追捕。

Members of the p53 tumor suppressor family (p53, p63 and p73) play critical roles in cell function, animal development and tumor suppression. P63 in particular is known to be crucial for the development of the epidermis. p63 mRNAs can be transcribed through two promoters to produce different N-termini that determine whether they contain (TA) or lack (DN) a full activation domain. TAp63 has been recently proposed to direct keratinocyte commitment during embryogenesis, while DNp63 is the dominant isoform found in both normal and neoplastic keratinocytes with high proliferative potential. Since the molecular mechanisms underlying p63 functions are still largely unknown, we propose to study this by the following approaches. First, we have performed exhaustive yeast two hybrid screening using a human keratinocyte cDNA library and have identified 4 novel p63 interactive partners. We are currently investigating biological functions that are mediated by p63 and its binding partners. Second, the cross talk between p63 and its family members (p53 and TAp63) will be investigated. It has been found that DNp63, the major p63 isoform in keratinocytes, can suppress the activity of p53 and TAp63 in reporter assays. We plan to examine whether DNp63 can inhibit the activity of p53 and TAp63 in vivo, and whether such activity is regulated by the p63-bidning proteins. Third, we will search for direct target genes bound by p63 in keratinocytes using both chromosome immunoprecipitation protocol and DNA microarray analysis. Once those genes are identified, how p63 (together with its binding proteins) regulates them and what their roles in keratinocytes will be further pursued.