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。人类plectin基因（PLEC）突变导致多种皮肤和骨骼肌疾病，这一事实突出了plectin在人体机械应力承受组织中的关键作用。迄今为止，人类胸纤病包括5种常染色体隐性疾病，即单纯大疱性表皮松解症伴肌营养不良（EBS- md）、EBS- md伴肌无力综合征（EBS- md - mys）、肢体带状肌营养不良2Q型（LGMD2Q）、EBS伴幽门闭锁（EBS- pa）和皮肤型EBS，以及常染色体显性变体EBS- ogna。凝集菌病属于罕见病，发病率低于5 / 10000。除了涉及皮肤和骨骼肌外，PLEC突变还引起广泛的心脏病表现。然而，目前对凝集素及其个体同种异构体在正常和患病心脏中的作用知之甚少。目的：1)凝集素缺乏对心功能、形态和生化的影响？2)急性剧烈运动如何影响plectin敲除（KO）小鼠的心脏病理？3)四种主要的plectin亚型在心肌组织和心肌细胞中的功能作用是什么？4)选定的药物能否改善缺乏凝集素的人心肌细胞的细胞骨架和线粒体病理？方法：我们将采用多层次实验方法来实现我们的目标：对plectin KO小鼠的体内研究将包括跑步机运行、超声心动图、标准和长期心电图。移植的心脏将通过光镜、免疫荧光、电子显微镜、免疫印迹、蓝色天然凝胶电泳和PCR分析进行研究。Plectin同种异构体的相关功能将通过对同种异构体特异性KO小鼠和心肌细胞的研究来解决。凝集素缺乏的人诱导多能干细胞将成为两种孤儿药细胞保护作用评价的实验基础，具有广阔的治疗潜力。创新：我们坚信，我们的项目将为我们目前对plectin和plectin亚型在正常和病变心脏组织中的作用的理解打开一个全新的篇章。除了更深入地了解与凝血素相关的心脏疾病的病理生理外，概述的项目将回答体育活动和所选的两种药物是否以及在多大程度上改变KO细胞和小鼠的心肌病理。因此，我们的工作也具有转化潜力，以改善患者的临床咨询，并可能有助于为新的治疗选择铺平道路。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博士Schröder教授

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