Characterization and regulation of wild-type and mutant TASK-1 two pore domain potassium channels indicated in pulmonary arterial hypertension.
Characterization and regulation of wild-type and mutant TASK-1 two pore domain potassium channels indicated in pulmonary arterial hypertension.
复制标题
DOI：
10.1113/jp277275
复制
发表时间：
2019-03
期刊：
影响因子：
--
通讯作者：
Mathie A
中科院分区：
文献类型：
--
作者：
Cunningham KP;Holden RG;Escribano-Subias PM;Cogolludo A;Veale EL;Mathie A
Task-1通道基因（KCNK 3）已被确定为遗传性肺动脉高压（PAH）的可能致病基因。在本研究中，我们发现PAH患者中发现的新型突变的TASK-1通道与野生型TASK-1通道相比具有大幅降低的电流。这些突变的Task-I通道位于质膜上，与野生型Task-I通道的程度相同。ONO-RS-082和碱性pH 8.4均激活了ASK-1通道，但不能通过突变型ASK-1通道恢复电流。我们发现，鸟苷酸环化酶激活剂riociguat（一种治疗PAH的新药物）可增强通过ASK-1通道的电流，但不能恢复通过突变型ASK-1通道的电流。肺动脉高压（PAH）影响每百万人中有15-50人。KCNK 3是编码双孔结构域钾通道任务-1（K2P3.1）的基因，已被确定为遗传性PAH中可能的致病基因。最近，在PAH患者的KCNK 3中发现了两个新的突变：G106 R和L214 R。本研究旨在表征野生型（WT）和突变型TASK-1通道的功能特性和调节，并确定这些通道如何有助于PAH及其治疗。使用全细胞膜片钳电生理学测量通过在tsA 201细胞中瞬时表达的WT和突变的人TASK-1通道的电流。使用共聚焦显微镜观察荧光标记通道的定位，并用细胞内和细胞上蛋白质印迹定量。G106 R或L214 R突变通道位于质膜上的程度与WT通道相同;然而，与WT ASK-1通道相比，其电流显著降低。通过这些突变通道的功能性电流不能使用WT ASK-1通道的激活剂（pH 8.4，ONO-RS-082）恢复。鸟苷酸环化酶激活剂riociguat可增强通过WT TASK-1通道的电流;然而，与研究的其他激活剂相似，riociguat对通过突变TASK-1通道的电流无任何影响。因此，在PAH中观察到的Task-I中的新突变实质上改变了这些通道的功能特性。通过这些通道的电流不能被ASK-1通道的激活剂恢复。利奥西呱增强通过ASK-1通道的电流可能有助于其在PAH治疗中的治疗获益。Task-1通道基因（KCNK 3）已被确定为遗传性肺动脉高压（PAH）的可能致病基因。在本研究中，我们发现PAH患者中发现的新型突变的TASK-1通道与野生型TASK-1通道相比具有大幅降低的电流。这些突变的Task-I通道位于质膜上，与野生型Task-I通道的程度相同。ONO-RS-082和碱性pH 8.4均激活了ASK-1通道，但不能通过突变型ASK-1通道恢复电流。我们发现，鸟苷酸环化酶激活剂riociguat（一种治疗PAH的新药物）可增强通过ASK-1通道的电流，但不能恢复通过突变型ASK-1通道的电流。
The TASK‐1 channel gene (KCNK3) has been identified as a possible disease‐causing gene in heritable pulmonary arterial hypertension (PAH). In the present study, we show that novel mutated TASK‐1 channels, seen in PAH patients, have a substantially reduced current compared to wild‐type TASK‐1 channels. These mutated TASK‐1 channels are located at the plasma membrane to the same degree as wild‐type TASK‐1 channels. ONO‐RS‐082 and alkaline pH 8.4 both activate TASK‐1 channels but do not recover current through mutant TASK‐1 channels. We show that the guanylate cyclase activator, riociguat, a novel treatment for PAH, enhances current through TASK‐1 channels but does not recover current through mutant TASK‐1 channels. Pulmonary arterial hypertension (PAH) affects ∼15–50 people per million. KCNK3, the gene that encodes the two pore domain potassium channel TASK‐1 (K2P3.1), has been identified as a possible disease‐causing gene in heritable PAH. Recently, two new mutations have been identified in KCNK3 in PAH patients: G106R and L214R. The present study aimed to characterize the functional properties and regulation of wild‐type (WT) and mutated TASK‐1 channels and determine how these might contribute to PAH and its treatment. Currents through WT and mutated human TASK‐1 channels transiently expressed in tsA201 cells were measured using whole‐cell patch clamp electrophysiology. Localization of fluorescence‐tagged channels was visualized using confocal microscopy and quantified with in‐cell and on‐cell westerns. G106R or L214R mutated channels were located at the plasma membrane to the same degree as WT channels; however, their current was markedly reduced compared to WT TASK‐1 channels. Functional current through these mutated channels could not be restored using activators of WT TASK‐1 channels (pH 8.4, ONO‐RS‐082). The guanylate cyclase activator, riociguat, enhanced current through WT TASK‐1 channels; however, similar to the other activators investigated, riociguat did not have any effect on current through mutated TASK‐1 channels. Thus, novel mutations in TASK‐1 seen in PAH substantially alter the functional properties of these channels. Current through these channels could not be restored by activators of TASK‐1 channels. Riociguat enhancement of current through TASK‐1 channels could contribute to its therapeutic benefit in the treatment of PAH. The TASK‐1 channel gene (KCNK3) has been identified as a possible disease‐causing gene in heritable pulmonary arterial hypertension (PAH). In the present study, we show that novel mutated TASK‐1 channels, seen in PAH patients, have a substantially reduced current compared to wild‐type TASK‐1 channels. These mutated TASK‐1 channels are located at the plasma membrane to the same degree as wild‐type TASK‐1 channels. ONO‐RS‐082 and alkaline pH 8.4 both activate TASK‐1 channels but do not recover current through mutant TASK‐1 channels. We show that the guanylate cyclase activator, riociguat, a novel treatment for PAH, enhances current through TASK‐1 channels but does not recover current through mutant TASK‐1 channels.