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的变化。这一认识的增加将导致对伤口愈合和牛皮癣等过度增殖和炎症过程的具体和有效的治疗。角质形成细胞中的分子信号通常激活多条平行的细胞内通路。明确关键的信号转导蛋白以及转导特定平行效应的蛋白将极大地加深我们对表皮调控过程的理解。该方法有四个基本步骤：识别角质形成细胞中作用的分子信号，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开发这些过程的特定修饰。在已经完成了第一步之后，我们在本提案中将重点放在最后三步。利用DNA转染和特异性抗体，将确定两个生长因子/细胞因子家族的信号转导机制，即EGF/TGFpha和TNFpha/IL-1家族。两者在皮肤炎症过程中都是极其重要的。将对AP1、NFkappaB和C/EBPbeta蛋白的转录因子激活模式进行表征。它们调节健康和患病的表皮中的基因表达。最后，利用特定的药物、反义寡核苷酸和靶DNA结合位点来抑制参与信号转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.