SIGNAL TRANSDUCTION MECHANISMS IN EPIDERMIS

这项工作的长期目标是增加我们对调节表皮基因表达的机制的理解，以及在疾病中发生的机制变化。这种增加的理解将导致对伤口愈合和牛皮癣等增生性和炎症过程的特异性和有效的治疗。角质形成细胞中的分子信号通常激活多个平行的细胞内通路。定义关键信号转导蛋白，以及转导特定平行效应的蛋白将大大增加我们对表皮调节过程的理解。该方法有四个基本步骤：识别在角质形成细胞中起作用的分子信号，定义相关的信号转导机制，表征转录因子激活的模式，并利用分子生物学的最新发现对这些过程进行特定的修饰。在已经完成了第一步之后，我们在本建议中集中注意最后三个步骤。使用DNA转染和特异性抗体，将定义生长因子/细胞因子的两个家族，EGF/TGFalpha和TNFalpha/IL-1家族的信号转导机制。两者在皮肤炎症过程中都极为重要。转录因子激活的模式将被表征为AP1， NFkappaB和C/EBPbeta蛋白。它们调节健康和患病表皮的基因表达。最后，我们将利用特定的药物、反义寡核苷酸和靶向DNA结合位点来抑制参与信号传导和基因表达调控的蛋白质，以了解它们在表皮生物学和病理学中的作用，并开发特异性的治疗方法。

The long term objective of this work is to increase our understanding of the mechanisms that regulate gene expression in epidermis, and the changes in the mechanisms that occur in diseases. This increased understanding will lead to specific and effective treatments of such hyperproliferative and inflammatory processes as wound healing and psoriasis. The molecular signals in keratinocytes commonly activate multiple parallel intracellular pathways. Defining the pivotal signal transducing proteins, as well as the proteins that transduce the specific parallel effects will greatly increase our understanding of the regulatory processes in epidermis. The approach has four basic steps: to identify the molecular signals that operate in keratinocytes, to define the relevant signal transduction mechanisms, to characterize the patterns of transcription factor activation and to develop specific modifications of these processes using latest discoveries of molecular biology. Having already completed the first step, we focus in this proposal on the last three steps. Using DNA transfection and specific antibodies, the signal transduction mechanisms will be defined for two families of growth factors/cytokines, the EGF/TGFalpha and the TNFalpha/IL-1 family. Both are extremely important in cutaneous inflammatory processes. The patterns of transcription factor activation will be characterized for AP1, NFkappaB and C/EBPbeta proteins. These regulate gene expression in healthy and diseased epidermis. Finally, the proteins involved in signaling and regulation of gene expression will be inhibited using specific drugs, antisense oligonucleotides and target DNA binding sites in order to understand their roles in epidermal biology and pathology, and to develop specific therapeutic approaches.