Regulation of Cav1.2 Trafficking by GJA1-20k and cBIN1

GJA1-20k 和 cBIN1 对 Cav1.2 贩运的监管

基本信息

批准号：
10658983
负责人：
TingTing Hong
金额：
$ 56.14万
依托单位：
UNIVERSITY OF UTAH
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-01 至 2025-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10658983
关键词：
Actins Affect American Animals Basic Science Biological Calcium Cardiac Cardiac Myocytes Cardiac health Cardiomyopathies Cell Line Cell model Cells Connexin 43 Coupling Cytoskeleton Data Development Disease Epidemic Functional disorder Genetic Goals Heart Heart Diseases Heart failure Homeostasis Human Impairment In Vitro Intercalated disc L-Type Calcium Channels Laboratories Maintenance Membrane Membrane Biology Methods Microtubules Modeling Molecular Movement Mus Muscle Cells Myocardium Outcome Pathologic Pathway interactions Publishing Recycling Regulation Relaxation Reporting Research Resources Ryanodine Receptor Calcium Release Channel Source Stress Surface Syndrome Testing Therapeutic United States United States National Institutes of Health Ventricular Vesicle absorption biosignature extracellular extracellular vesicles gene therapy heart function improved in vivo innovation mouse model novel novel diagnostics novel marker novel therapeutic intervention novel therapeutics pharmacologic preservation restoration targeted delivery targeted treatment therapeutic development therapy development tool trafficking translational impact translational potential vesicular release

项目摘要

In normal hearts, the transverse tubules (t-tubules) concentrate L-type calcium channels (LTCCs) to initiate the beat-to-beat intracellular calcium transients which contribute to the regulation of cardiac contraction and relaxation. An altered calcium transient is a key pathophysiological sign of failing heart. However, mechanisms of maintenance of LTCC expression at t-tubule microdomains for optimal calcium-induced-calcium-release (CICR) remain poorly understood. Understanding the dynamic regulation of calcium handling microdomains at t-tubules, and in particular LTCC regulation at the microdomains, is needed to understand the pathophysiology of failing hearts and to identify new pathways and molecules that can be targeted for heart failure therapy development. The overall objective of this MPI application is to further our mechanistic understanding of how LTCC expression at t-tubule cBIN1-microdomains is maintained and why LTCC localization is altered in heart failure. We will explore the central hypothesis that homeostatic LTCC expression at t-tubules is highly dynamic and maintained by both internal delivery and external delivery. We expect that the internal delivery is determined by intracellular actin reservoirs of LTCCs organized at Z-disks by a newly identified actin nucleator GJA1-20k (Aim 1, RMS). We also expect that there is a local extracellular reservoir of cBIN1 vesicles (Aim 2, TTH), which feed t-tubule cBIN1-microdomains from other regions of the heart to modulate LTCC expression at t-tubule surfaces. In heart failure, both sources are depleted yet could be exogenously restored. The resources of a membrane biology lab (TTH) and a trafficking lab focused on heart failure progression (RMS) are combined in this application for the proposed research plan. The rationale that underlies the proposed research is that LTCCs at t-tubule microdomains are dynamically regulated from both inside and out, are reduced in heart failure, and can be restored presenting a novel therapy for heart failure. The proposed research is innovative because it will identify new regulatory mechanisms of remodeled myocardium during heart failure progression, and lead to the establishment of molecules and pathways that can be targeted for therapy development. The proposal has a strong premise because it is based on extensive published and preliminary data from successful in vitro cell-free studies, intact cell line and primary cardiomyocyte studies, and successful genetic and in vivo animal heart failure models. The significance is high because it will lead to development of new therapeutic strategies that will allow preservation and restoration of efficient excitation-contraction coupling in diseased hearts.

在正常的心脏中，横向小管（T管）浓缩L型钙通道（LTCCS）启动Beat-Beat细胞内钙瞬变，这有助于调节心脏收缩和放松。改变的钙瞬态是一个关键的病理生理标志心脏失败。但是，在T-pubule微域中LTCC表达的维持机制最佳钙诱导的 - 释放（CICR）的理解还不足。了解动态调节钙处理微域在T管处的调节，尤其是LTCC调节。需要微域，需要了解心脏失败的病理生理学并识别新的可以针对心力衰竭疗法发展的途径和分子。该MPI应用的总体目的是进一步我们对维持T-Tubule CBIN1-微分类域的LTCC表达以及为何在LTCC定位改变的原因。心脏衰竭。我们将探讨以下假设，即稳态LTCC表达在t-小管处高度动态，并通过内部交付和外部交付维护。我们期望内部递送由LTCC的细胞内肌动蛋白储层确定新鉴定的肌动蛋白成核GJA1-20K（AIM 1，RMS）。我们还希望有一个当地 CBIN1囊泡的细胞外库（AIM 2，TTH），从心脏的其他区域调节LTCC表达在T型表面。在心力衰竭中，两者来源耗尽，但可以外源恢复。膜生物学实验室（TTH）和贩运实验室的资源专注于心力衰竭在此应用程序中，将进步（RMS）合并为拟议的研究计划。理由拟议的研究是t-pubule微区域的LTCC受到动态调节从内部和外部都可以减少心力衰竭，并且可以恢复出来的新疗法为了心力衰竭。拟议的研究具有创新性，因为它将确定心力衰竭进展过程中重塑心肌，并导致分子的建立以及可以针对治疗发展的途径。该提议的前提很强因为它基于成功的无体外细胞的广泛发布和初步数据研究，完整的细胞系和主要心肌细胞研究以及成功的遗传和体内动物心力衰竭模型。意义很高，因为它将导致新的治疗性发展将允许保存和恢复有效的激发反应耦合的策略患病的心。