Impaired protein stability or trafficking underlies diverse ion channelopathies and represents an unexploited unifying principle for developing common treatments for otherwise dissimilar diseases. Ubiquitination limits ion channel surface density, but targeting this pathway for the purposes of basic study or therapy is challenging because of its prevalent role in proteostasis. We developed engineered deubiquitinases (enDUBs) that enable selective ubiquitin chain removal from target proteins to rescue the functional expression of disparate mutant ion channels that underlie long QT syndrome (LQT) and cystic fibrosis (CF). In an LQT type 1 (LQT1) cardiomyocyte model, enDUB treatment restored delayed rectifier potassium currents and normalized action potential duration. CF-targeted enDUBs synergistically rescued common (ΔF508) and pharmacotherapy-resistant (N1303K) CF mutations when combined with the US Food and Drug Administation (FDA)-approved drugs Orkambi (lumacaftor/ivacaftor) and Trikafta (elexacaftor/tezacaftor/ivacaftor and ivacaftor). Altogether, targeted deubiquitination via enDUBs provides a powerful protein stabilization method that not only corrects diverse diseases caused by impaired ion channel trafficking, but also introduces a new tool for deconstructing the ubiquitin code in situ.

受损的蛋白质稳定性或运输是多种离子通道病的基础，并且代表了一种尚未开发的统一原则，用于开发针对其他不同疾病的通用治疗方法。泛素化限制了离子通道的表面密度，但由于其在蛋白质稳态中的普遍作用，将这一途径靶向用于基础研究或治疗具有挑战性。我们开发了工程去泛素酶 (enDUBs)，它能够从靶蛋白中选择性地去除泛素链，以挽救长 QT 综合征 (LQT) 和囊性纤维化 (CF) 的不同突变离子通道的功能表达。在 LQT 1 型 (LQT1) 心肌细胞模型中，enDUB 治疗恢复了延迟整流钾电流和标准化动作电位持续时间。当与美国食品和药物管理局 (FDA) 批准的药物 Orkambi（lumacaftor/ivacaftor）和 Trikafta（elexacaftor/tezacaftor/ivacaftor 和 ivacaftor ）。总而言之，通过 enDUB 进行的靶向去泛素化提供了一种强大的蛋白质稳定方法，不仅可以纠正由离子通道运输受损引起的多种疾病，而且还引入了一种原位解构泛素代码的新工具。