Plectin function in normal and diseased hearts

更广泛的研究背景：Plectin是一种具有多种细胞功能的细胞骨架连接蛋白。它在人类机械应力承载组织中的关键作用突出表现在人类plectin基因（PLEC）突变导致各种皮肤和骨骼肌疾病的事实。迄今为止，人类plectinopathies组包括五种常染色体隐性疾病，即单纯性大疱性表皮病伴肌营养不良（EBS-MD）、EBS-MD伴肌无力综合征（EBS-MD-MyS）、肢带型肌营养不良2 Q型（LGMD 2 Q）、EBS伴幽门闭锁（EBS-PA）和仅皮肤型EBS，以及常染色体显性变体EBS-Ogna。凝集素病属于罕见疾病组，发病率低于5/10，000。除了皮肤和骨骼肌受累，PLEC突变还引起广泛的心脏病表现。然而，很少是目前所知的作用，plectin和它的个别异构体在正常和患病hearts.Objectives：1）如何plectin缺乏影响心脏功能，形态和生化？2)急性剧烈体力活动如何影响plectin基因敲除（KO）小鼠的心脏病理学？3)心肌组织和心肌细胞中四种主要的网蛋白异构体的功能作用是什么？4)选择性药物能改善人心肌细胞的细胞骨架和线粒体病变吗？方法：我们将应用多层次的实验方法来解决我们的目标：在体内研究plectin基因敲除小鼠将包括跑步机运行，超声心动图，标准和长期心电图。将通过光学显微镜、免疫荧光和电子显微镜、免疫印迹、蓝色天然凝胶电泳和PCR分析研究取出的心脏。将通过在同种型特异性KO小鼠和心肌细胞中的研究来解决凝集素同种型相关功能。Plectin缺陷的人诱导多能干细胞将成为评价两种孤儿药细胞保护作用的实验基础，具有很好的治疗潜力。创新：我们坚信，我们的项目将打开一个全新的篇章，在我们目前的理解的作用，plectin和plectin亚型在正常和患病的心脏组织。除了更深入地了解与plectin相关的心脏疾病的病理生理学之外，概述的项目还将回答这样一个问题，即体力活动和两种选择的药物是否以及在多大程度上可以改变KO细胞和小鼠的心肌病理学。因此，我们的工作也具有改善患者临床咨询的转化潜力，并可能有助于为plectinopathies的新治疗方案铺平道路。主要研究人员：维也纳医科大学Lilli Winter博士和埃尔兰根大学医院Rolf Schröder教授博士

Wider research context: Plectin is a cytoskeletal linker protein with a multitude of cellular functions. Its pivotal role in mechanical stress-bearing tissues in humans is highlighted by the fact that mutations in the human plectin gene (PLEC) cause a variety of skin and skeletal muscle diseases. The group of human plectinopathies thus far comprises five autosomal-recessive disorders, namely epidermolysis bullosa simplex with muscular dystrophy (EBS-MD), EBS-MD with myasthenic syndrome (EBS-MD-MyS), limb girdle muscular dystrophy type 2Q (LGMD2Q), EBS with pyloric atresia (EBS-PA), and skin-only EBS, as well as the autosomal-dominant variant EBS-Ogna. Plectinopathies belong to the group of rare diseases with an incidence of less than 5 affected individuals in 10,000. Beyond skin and skeletal muscle involvement, PLEC mutations also cause a broad spectrum of cardiac disease manifestations. However, very little is currently known about the role of plectin and its individual isoforms in normal and diseased hearts.Objectives: 1) How does plectin deficiency impact on the cardiac function, morphology and biochemistry? 2) How do acute strenuous physical activities impact on the cardiac pathology in plectin knock out (KO) mice? 3) What is the functional role of the four major plectin isoforms in cardiac muscle tissue and cardiomyocytes? 4) Can selected drugs ameliorate the cytoskeletal and mitochondrial pathology in plectin-deficient human cardiomyocytes?Approach: We will apply a multilevel experimental approach to address our goals: in vivo studies on plectin KO mice will comprise treadmill running, echocardiography, standard and long-term electrocardiogram. Explanted hearts will be studied by light-, immunofluorescence-, and electron microscopy, immunoblotting, blue native gel electrophoresis and PCR analyses. Plectin isoform related functions will be tackled by studies in isoform-specific KO mice and cardiomyocytes. Plectin-deficient human induced pluripotent stem cells will be the experimental basis for the evaluation of cell protective effects of two orphan drugs, which have a promising therapeutic potential. Innovation: We strongly believe that our project will open a completely new chapter in our current understanding of the role of plectin and plectin isoforms in normal and diseased cardiac tissue. Beyond deeper insights into the pathophysiology of plectin-related cardiac diseases, the outlined project shall answer the question if, and to what extent, physical activity and the two chosen drugs can alter the cardiac muscle pathology in KO cells and mice. Thus, our work also has the translational potential to improve the clinical counseling of patients and may help to pave the way towards new treatment options for plectinopathies. Primary researchers involved: Dr. Lilli Winter, Medical University of Vienna & Prof. Dr. Rolf Schröder, University Hospital Erlangen