COBRE PROJ 8: ROLES OF IKK ?LPHA IN SKIN DEVELOPMENT AND DYSPLASIA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 李秋堂，派 该项目的长期目标是阐明IKKalpha对表皮动态平衡的影响的细胞和分子机制。IKKalpha是核因子-kappaB信号通路中IKK复合体的一个亚单位。IKKalpha基因敲除小鼠出生时就死于与角质形成细胞增殖增加和终末分化受损相关的皮肤缺陷。IKKalpha在角质形成细胞中的功能不依赖于其激酶活性和核因子-kappaB信号通路。IKKalpha调节角质形成细胞增殖和分化的机制尚不清楚。在目前的研究中，我们将验证IKKalpha调节角质形成细胞周期并在皮肤中作为肿瘤抑制基因发挥作用的假设。 具体地说，将解决以下问题：(1)IKKalpha在角质形成细胞细胞周期和细胞周期检查点的调节中扮演什么角色？(2)角质形成细胞中与IKKalpha相互作用的蛋白是什么？(3)这些相互作用的蛋白如何参与角质形成细胞中的IKKalpha信号转导？(4)IKKalpha在皮肤中作为肿瘤抑制因子发挥作用吗？ 细胞周期分析和功能研究将结合遗传学、细胞学和生物化学方法，在胚胎18.5天时从野生型或IKKalpha缺陷胚胎中分离出原代角质形成细胞。从IKKalpha免疫沉淀和质谱学中产生的数据将被进一步验证和表征，以在分子水平上理解IKKalpha功能。我们将检测暴露在诱变致癌物质下的IKKalpha/-小鼠的皮肤肿瘤易感性和转移潜力，并检查IKKalpha/-小鼠肿瘤中IKKalpha基因位点杂合性频率的丢失。这些知识将对阐明皮肤癌等临床相关问题非常重要。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Qiutang Li, PI The long-term goal of this project is to elucidate the cellular and molecular mechanism by which IKKalpha exerts its effects on epidermal homeostasis. IKKalpha is a subunit of IKK complexes in the NF-kappa B signaling pathway. IKKalpha knockout mice die at birth from the skin defects associated with increased proliferation and impaired terminal differentiation in keratinocytes. The function of IKKalpha in keratinocytes is independent from its kinase activity and NF-kappa B signaling pathway. The mechanism by which the IKKalpha regulates keratinocyte proliferation and differentiation remains unclear. In the present studies, we will test the hypothesis that IKKalpha regulates keratinocyte cell cycle and functions as a tumor suppressor gene in skin. Specifically, the following questions will be addressed: (1) What are the roles of the IKKalpha in regulation of the keratinocyte cell cycle and cell cycle checkpoint? (2) What are the IKKalpha-interacting proteins in keratinocyte? (3) How do those interacting proteins participate in the IKKalpha signaling in the keratinocytes? (4) Does IKKalpha function as a tumor suppressor in skin? Cell cycle analysis and functional studies will be performed in the primary keratinocytes isolated from either wild-type or the IKKalpha deficient embryos at embryonic day 18.5 using a combination of genetics, cytological, and biochemical approaches. The data that have been generated from IKKalpha immunoprecipitation and mass spectrometry will be further validated and characterized to understand the IKKalpha function at a molecular level. We will examine skin tumor susceptibility and metastatic potential in IKKalpha+/- mice exposed to mutagenic carcinogen and check the loss of heterozygosity frequency at the IKKalpha locus in IKKalpha+/- mouse tumors. The knowledge will be important for elucidating clinically relevant problems such as skin cancers.