CORNIFIED ENVELOPE ASSOCIATED PROTEINS AND PERMEABILITY BARRIER FUNCTION

虽然结构蛋白在表皮机械屏障中的作用是明确的，但它们在渗透性屏障中的作用尚不清楚。我们假设，选择的结构和酶蛋白，即，那些既受Ca++调节又与皮层包膜（CE）相关的蛋白质：外皮蛋白、兜甲蛋白、转氨酶1（TG 1）、原丝蛋白和K1/10，是屏障稳态调节/所需的。该提案将评估这些蛋白质中哪些受渗透性屏障要求的调节，以及这些CE相关蛋白质如何与脂质结合包膜（LBE）和富含脂质的细胞外膜层合作，从渗透性屏障中分离。具体地，在目标#1中，我们将通过以下方式确定哪些CE相关蛋白受改变的屏障需求调节，以及Ca++是否调节它们的表达：a）在无毛小鼠中，在急性屏障破坏（丙酮、胶带剥离）后和必需脂肪酸缺乏（EFAD）中，测量CE相关蛋白的mRNA/蛋白表达的时间过程。B）确定细胞外Ca++的变化（在体内通过超声促渗和通过浸泡）是否调节调节的CE蛋白的表达;以及钙受体（CaR）和电压敏感性Ca++通道在这些变化中的参与。c）确定CE相关蛋白表达的瞬时降低是否促进屏障恢复。使用三种转基因过表达（外皮蛋白、K6/16和前聚丝蛋白）小鼠模型，这些蛋白质中的一种干扰渗透性屏障稳态和板层体分泌。 在目标#2中，我们将通过以下方式确定哪些CE相关蛋白是正常屏障稳态所需的，以及这些蛋白的改变导致屏障异常的机制：在患有板层状鱼鳞病（LI; TG 1缺失）、表皮炎性角化过度（EHK;K1或10突变）、Siemens大疱性鱼鳞病（IBS; K2 e突变）、掌跖角化病（NSPPK; K1突变）、鱼鳞病、角化病（NSPPK; K1突变）、寻常鱼鳞病（聚丝蛋白原缺乏）、Vohwinkle病（兜甲蛋白突变）以及外皮蛋白和K10鼠敲除动物的患者中。B）评估CE相关蛋白影响渗透性屏障功能的机制。

Although the role of structural proteins in the epidermal mechanical barrier is clear, their role in the permeability barrier is unknown. We hypothesize that selected structural and enzymatic proteins; i.e., those that are both regulated by Ca++ and associated with the cornified envelope (CE): involucrin, loricrin, transglutaminase 1 (TG1), pro-fillaggrin, and K1/10, are regulated/required for barrier homeostasis. This proposal will assess which of these proteins are regulated by permeability barrier requirements, and how these CE-associated proteins, in partnership with the lipid bound envelope (LBE) and the lipid-enriched extracellular lamellae, from the permeability barrier. Specifically, in Aim #1 we will determine which CE- associated proteins are regulated by altered barrier requirements, and whether Ca++ regulates their expression, by: a) measuring the time course of mRNA/protein expression for the CE-associated proteins after acute barrier disruption (acetone, tape stripping) and in essential fatty acid deficiency (EFAD) in hairless mice. b) Ascertaining whether changes in extracellular Ca++ (in vivo by sonophoresis and by immersion) modulate expression of the regulated CE protein(s); and the participation of the calcium receptor (CaR) and voltage-sensitive Ca++ channels in these changes. c) Determining whether the transient decrease in CE-associated protein expression facilitates barrier recovery. Using three transgenic over- expressing (involucrin, K6/16, and pro-filaggrin) murine models, and one of these proteins interferes with permeability barrier homeostasis and lamellar body secretion. In Aim #2, we will determine which CE-associated proteins are required for normal barrier homeostasis, and the mechanisms by which alterations in these proteins lead to barrier abnormalities, by: a) Assessing homeostasis in human and murine models with specific deletions or mutations of CE-associated proteins; i.e., in patients with lamellar ichthyosis (LI; TG1 deletion), epidermolytic hyperkeratoses (EHK;K1 or 10 mutation), ichethyosis bullosa of Siemens (IBS; K2e mutation), palmo-plantar keratoderma (NSPPK; K1 mutation), ichthyosis, Keratoderma (NSPPK; K1 mutation), ichthyosis vulgaris (pro-filaggrin deficiency), Vohwinkle's disease (loricrin mutation), plus involucrin and K10 murine knockout animals. b) Assessing the mechanisms whereby CE-associated proteins influence permeability barrier function.