Targeting the Microtubule EB1-CLASP2 Complex Modulates Na V 1.5 at Intercalated Discs

作者：Gerard A. Marchal, Mariam Jouni, David Y. Chiang, Marta Pérez-Hernández, Svitlana Podliesna, Nuo Yu, Simona Casini, F Potet, Christiaan C. Veerman, Mischa Klerk, Elisabeth M. Lodder, Isabella Mengarelli, Kaomei Guan, Carlos G. Vanoye, Eli Rothenberg, Flavien Charpentier, Richard Redon, Alfred L. George, Arie O. Verkerk, Connie R. Bezzina, Calum A. MacRae, Paul W. Burridge, Mario Delmar, Niels Galjart, Vincent Portero, Carol Ann Remme · 发表于：Circulation Research · 年份：2021 · DOI：10.1161/circresaha.120.318643 · 被引用次数：38 · 研究领域：Mitochondrial Function and Pathology、Cardiac electrophysiology and arrhythmias、Ion channel regulation and function

Rationale: Loss-of-function of the cardiac sodium channel Na V 1.5 causes conduction slowing and arrhythmias. Na V 1.5 is differentially distributed within subcellular domains of cardiomyocytes, with sodium current ( I Na ) being enriched at the intercalated discs (ID). Various pathophysiological conditions associated with lethal arrhythmias display ID-specific I Na reduction, but the mechanisms underlying microdomain-specific targeting of Na V 1.5 remain largely unknown. Objective: To investigate the role of the microtubule plus-end tracking proteins EB1 (end-binding protein 1) and CLASP2 (cytoplasmic linker associated protein 2) in mediating Na V 1.5 trafficking and subcellular distribution in cardiomyocytes. Methods and Results: EB1 overexpression in human-induced pluripotent stem cell-derived cardiomyocytes resulted in enhanced whole-cell I Na , increased action potential upstroke velocity ( V max ), and enhanced Na V 1.5 localization at the plasma membrane as detected by multicolor stochastic optical reconstruction microscopy. Fluorescence recovery after photobleaching experiments in HEK293A cells demonstrated that EB1 overexpression promoted Na V 1.5 forward trafficking. Knockout of MAPRE1 in human induced pluripotent stem cell-derived cardiomyocytes led to reduced whole-cell I Na , decreased V max , and action potential duration (APD) prolongation. Similarly, acute knockout of the MAPRE1 homolog in zebrafish ( mapre1b ) resulted in decreased ventricular conduction velo...