Contributions of Cardiac Myosin Binding Protein-C to Healthy and Failing Hearts

描述（由申请人提供）：心肌肌球蛋白结合蛋白-C对健康和衰竭心脏的贡献的摘要。我是一名心脏病专家，在德克萨斯A & M健康科学中心（HSC）医学院担任助理教授。我相信我的使命是进行有助于心力衰竭治疗的研究，并直接参与心力衰竭患者的治疗。虽然我在科学研究方面接受了良好的教育，但7年的临床培训使我成为一名独立研究者的发展暂停。因此，我的短期过渡目标包括获得新技能，开发资源，发表重要发现，并获得NIH R01级资金，以继续发展为独立研究者。这个指导研究职业发展奖（K08）提供了实现这些过渡目标的手段。research.我将重点阐明心肌肌球蛋白结合蛋白-C（MyBPC3）对健康和衰竭心脏的贡献。40岁的美国人一生中患心力衰竭（HF）的风险为20%。射血分数保留的HF（HFpEF），没有有效的治疗方法，使所有HF病例的患病率增加到约50%。粗肌丝肌球蛋白跨桥连接到细肌丝上的肌动蛋白，将储存的化学能转化为力，然后分离的循环形成了心脏收缩和舒张的基础。MyBPC3抑制与肌动蛋白的交叉桥相互作用。MyBPC3的磷酸化可能解除其抑制作用，促进跨桥循环。因此，我假设MyBPC3磷酸化调节跨桥循环以增强收缩性（产生力的能力）和松弛性（松弛的能力）。 本文将通过转基因小鼠模型来阐明MyBPC3的存在和磷酸化对心脏功能的影响。分别通过缺失MyBPC3基因和在MyBPC3（-/-）背景下表达磷酸化模拟MyBPC3突变体来实现对MyBPC3的存在和磷酸化的控制。初步数据强烈表明，MyBPC3缺失导致HF伴射血分数降低（HFrEF），MyBPC3磷酸化缺陷导致HFpEF。 我还将确定使用MyBPC 3磷酸化预防和治疗HFpEF的能力。治疗思路集中在MyBPC3磷酸化介导的收缩性和lustropy增强将维持足够的心脏功能而不需要在应激期间的肥大反应的可能性。将通过用通常引起舒张功能障碍的应激挑战组成性磷酸化MyBPC 3小鼠模型来测试预防。通过病毒基因转移诱导磷酸化MyBPC 3模拟物的表达和应激期间诱导的基因表达将决定治疗潜力。职业发展。一个来自全国各地的专家小组已经聚集起来提供指导。该团队由Solaro博士（跨桥自行车细灯丝调节方面的领先专家，初级 导师），Moss博士（MyBPC3和跨桥循环粗丝调节的领先专家）和Redfield博士（HFpEF的领先权威和大型动物模型专家）。此外，Hajjar博士（使用病毒基因转移治疗HF的领先专家）将作为一名 病毒载体构建顾问。德克萨斯A & M团队的一部分将提供机构支持和现场专业知识的保证。我将学习压力-容积的新技能 环测量以确认HFpEF，二维荧光差异凝胶电泳以鉴定MyBPC 3上的翻译后修饰，应激技术以诱导小鼠舒张功能障碍，以及病毒基因转移补充诱导基因表达以测试靶向MyBPC 3磷酸化作为潜在治疗。通过这个过程，我将开发新的病毒基因转移载体和诱导型基因表达载体的资源。此外，指导小组还将提供有关结果发表和NIH研究项目拨款（R01）准备的指导。环境我的主要任命是与系统生物学和转化医学（SBTM）的基础科学部门。SBTM部门已经产生了独立的调查人员，他们继续在学术机构担任主席。启动包提供了设备采购和实验室空间。SBTM和得克萨斯A & M HSC都有不同级别的调查人员，他们有技能，并热衷于合作。德克萨斯A & M HSC保证在5年内保护75%的工作致力于这项研究，而不受K08奖资助的影响。此外，得克萨斯A & M HSC已同意退还K08裁决产生的所有工资节省;因此，该协议对K08裁决产生了倍增效应。因此，我居住在一个良好的环境，发展为一个独立的调查员。摘要完成这些拟议的研究将提供新的技能，资源和发现。因此，资助这项提案将有助于解决一个令人烦恼的健康问题，并使一个开始的临床科学家走向独立研究的道路。

DESCRIPTION (provided by applicant): Abstract for Contributions of cardiac myosin binding protein-C to healthy and failing hearts Candidate. I am a cardiologist starting 2nd year as an assistant professor at Texas A&M Health Science Center (HSC) College of Medicine. I believe that my calling is to conduct research that can contribute to treatment of heart failure and directly participate in treatment of heart failure patients. Although I've received excellent education in scientific research, 7 total years of required dedicated clinical training has paused my development as an independent investigator. Thus, my short term transitional goals consist of acquiring new skills, developing resources, publishing important findings, and obtaining NIH R01 level funding to continue development toward independent investigator. This mentored research career development award (K08) provides the means to achieve these transitional goals. Research. I will focus on elucidating contributions of cardiac myosin binding protein-C (MyBPC3) to healthy and failing hearts. A 40 year old American has 20% life-time risk of developing heart failure (HF). HF with preserved ejection fraction (HFpEF), which there is no effective treatment, has increased prevalence to ~50% of all HF cases. The cycle of thick filament myosin cross-bridge attaching to actin on the thin filament, converting stored chemical energy to force, and then detaching forms the basis for contraction and relaxation of heart. MyBPC3 inhibits cross-bridge interaction with actin. Phosphorylation of MyBPC3 may release its inhibition to promote cross-bridge cycling. Thus, I hypothesize that MyBPC3 phosphorylation regulates cross- bridge cycling to enhance both contractility (ability to generate force) and lusitropy (ability to relax). I will elucidate the effects of presence and phosphorylation of MyBPC3 on heart function through the use genetically modified mouse models. Control of presence and phosphorylation of MyBPC3 is achieved through deletion of MyBPC3 gene and expression of phosphorylation mimetic MyBPC3 mutants on MyBPC3(- /-) background respectively. Preliminary data strongly suggests that MyBPC3 deletion leads to HF with reduced ejection fraction (HFrEF) and MyBPC3 phosphorylation deficiency leads to HFpEF. I will also determine the ability of using MyBPC3 phosphorylation to prevent and treat HFpEF. Therapeutic idea centers on the possibility that MyBPC3 phosphorylation mediated enhancements of contractility and lusitropy will maintain sufficient cardiac function without needing hypertrophic response during stress. Prevention will be tested through challenging constitutively phosphorylated MyBPC3 mouse model with stress that normally causes diastolic dysfunction. Inducing expression of phosphorylated MyBPC3 mimetic through viral gene transfer and induced gene expression during stress will determine treatment potential. Career Development. An expert team from across the country has assembled to provide mentoring. The team consists of Dr. Solaro (leading expert in thin filament regulation of cross-bridge cycling, primary mentor), Dr. Moss (leading expert in MyBPC3 and thick filament regulation of cross-bridge cycling), and Dr. Redfield (leading authority on HFpEF and expert in large animal models). In addition, Dr. Hajjar (leading expert in using viral gene transfer for HF therapy), will assist as a consultant on construction of virus vectors. Texas A&M portion of the team will provide assurance of institutional support and onsite expertise. I will learn new skills of pressure-volume loop measurements to confirm HFpEF, 2-dimensional fluorescence difference gel electrophoresis to identify post-translation modifications on MyBPC3, stress technique to induce diastolic dysfunction in mice, and viral gene transfer in compliment to inducible gene expression to test targeted MyBPC3 phosphorylation as potential treatment. Through the process, I will have developed new resources of viral gene transfer vector and inducible gene expression construct. Furthermore, the mentoring team will also provide guidance on publication of results and preparation of NIH research project grant (R01). Environment. My primary appointment is with basic science department of system biology and translational medicine (SBTM). The SBTM department has produced independent investigators that went on to hold chairmanships at academic institutions. Start-up package has provided equipment purchases and laboratory space. Both SBTM and Texas A&M HSC have investigators at various levels who have the skills and are enthusiastic to collaborate. Texas A&M HSC has guaranteed protected 75% effort dedicated to this research for 5-years independent of receiving K08 award funding. Furthermore, Texas A&M HSC has agreed to return all salary savings generated from K08 award; therefore, this agreement provides a multiplication effect on the K08 award. Thus, I reside in an excellent environment to develop as an independent investigator. Summary. Accomplishing these proposed studies will provide new skills, resources, and discoveries. Thus, funding this proposal will help to solve a vexing health problem and enable a beginning clinician scientist toward path of independent research.