PROFILAGGRIN IN EPIDERMAL DIFFERENTIATION AND FUNCTION

聚丝蛋白原在表皮分化和功能中的作用

基本信息

批准号：
6511916
负责人：
RICHARD B. PRESLAND
金额：
$ 9.12万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
1998
资助国家：
美国
起止时间：
1998-05-01 至 2004-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6511916
关键词：
calcium binding protein cell differentiation cell growth regulation genetically modified animals histogenesis immunocytochemistry intermediate filaments keratinocyte laboratory mouse nucleic acid probes nucleic acid sequence polymerase chain reaction protein structure function skin

项目摘要

DESCRIPTION: (Adapted from the applicant's abstract) - Profilaggrin is an abundant, highly phosphorylated, calcium-binding protein expressed in differentiating epidermal keratinocytes just prior to formation of cornified cells. Profilaggrin contains an N-terminal calcium-binding domain and multiple filaggrin units. Each region is proposed to have specific, distinct functions in vivo once profilaggrin is cleaved to yield the N-terminal and filaggrin peptides. The goal of this proposal is to understand the function(s) of these domains of profilaggrin by expression in keratinocytes of mutant proteins with a non-functional calcium-binding domain and by targeted disruption in embryonic stem cells to create profilaggrin-deficient mice. New evidence suggests that filaggrin, derived from profilaggrin by specific proteolysis, functions in cultured keratinocytes as a keratin-aggregating protein, leading to collapse of the keratin cytoskeleton, changes in cell shape, and cell cycle arrest. Filaggrin undergoes further proteolysis in vivo to free amino acids which bind water and are thought to maintain normal osmolarity of corneocytes. The hypotheses to be tested are (1) The calcium-binding domain of profilaggrin has a specific function(s) in regulating the calcium-dependent events of epidermal cornification, including profilaggrin expression and proteolytic processing to filaggrin, and (2) filaggrin, through its roles as a keratin-associated protein and as the major source of hygroscopic amino acids, performs critical functions in regulating normal corneocyte maturation and function. To address these questions, the specific aims proposed are to (1) Determine the function of the N-terminal calcium-binding domain of profilaggrin by first abolishing its ability to bind calcium and then expressing it in stable keratinocyte cell lines and in transgenic mice and (2) determine the function(s) of profilaggrin in vivo by targeted disruption in mice. Profilaggrin-deficient mice will allow assessment of the functional significance of profilaggrin in vivo. This work should also provide a firm basis for understanding the biochemical significance of reduced or absent profilaggrin expression in skin diseases such as ichthyosis vulgaris and psoriasis and the failure of profilaggrin processing to filaggrin in the severe scaling disorder Harlequin ichthyosis.

描述：（改编自申请人的摘要）-Profilaggrin是一个大量，高度磷酸化的钙结合蛋白在在形成薄层之前，分化表皮角质形成细胞细胞。 profilaggrin包含一个N末端钙结合域和多个Filaggrin单元。建议每个区域具有特定的一旦裂解profilaggrin以产生，体内的不同功能 N末端和丝林肽。该提议的目的是通过表达在突变蛋白具有非功能性钙结合的角质形成细胞域和胚胎干细胞中的靶向破坏以创建缺陷小鼠。新证据表明，菲尔格林（Filaggrin）得出从特定蛋白水解的profilaggrin，在培养中的功能角质形成细胞作为角蛋白聚集蛋白，导致崩溃角蛋白细胞骨架，细胞形状的变化和细胞周期停滞。 Filaggrin在体内进一步进行蛋白水解，以游离氨基酸结合水，被认为可以维持正常的角膜细胞的渗透压。要测试的假设是（1） Profilaggrin在调节钙依赖性方面具有特定功能表皮植物化的事件，包括叶子蛋白表达和蛋白水解处理至Filaggrin，以及（2）Filaggrin，通过其角色作为角蛋白相关的蛋白质，作为吸湿氨基的主要来源酸，在调节正常角膜细胞方面具有关键功能成熟和功能。为了解决这些问题，具体目的提议的是（1）确定N末端钙结合的功能 profilaggrin的领域首先废除其结合钙的能力和然后在稳定的角质形成细胞系和转基因小鼠中表达它（2）通过靶向确定体内profilaggrin的功能小鼠的破坏。缺陷型小鼠将允许评估 profilaggrin在体内的功能意义。这项工作也应该为理解生化意义提供了坚定的基础皮肤疾病（例如鱼质病和牛皮癣以及profilaggrin加工的失败在严重的缩放障碍群虫鱼裂中丝蛋白。