KCNH2 encodes a nuclear-targeted polypeptide that mediates hERG1 channel gating and expression.
KCNH2 encodes a nuclear-targeted polypeptide that mediates hERG1 channel gating and expression.
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DOI：
10.1073/pnas.2214700120
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发表时间：
2023-01-17
影响因子：
11.1
通讯作者：
Jones, David K.
中科院分区：
文献类型：
--
作者：
Jain, Abhilasha;Stack, Olivia;Ghodrati, Saba;Sanchez-Conde, Francisco G.;Ukachukwu, Chiamaka U.;Salwi, Shreya;Jimenez-Vazquez, Eric N.;Jones, David K.
KCNH2 编码电压门控钾通道 hERG1。 hERG1 变异与年轻人猝死有关，包括宫内胎儿死亡、婴儿猝死综合征 (SIDS) 和癫痫原因不明猝死 (SUDEP)。在这里，我们鉴定了一种非传导的 KCNH2 编码多肽 hERG1NP，它在未成熟心肌细胞中上调，并且其靶向细胞核间接调节 hERG1 门控。这些数据确定了 hERG1 通道的调节机制，并可能代表与 hERG1 功能障碍相关疾病的治疗靶点。 KCNH2 编码 hERG1，这是一种电压门控钾通道，可在人体心脏组织中传导快速延迟整流钾电流 (IKr)。 hERG1是早期心脏发育过程中最先表达的通道之一，其功能障碍与宫内胎儿死亡、婴儿猝死综合征、心律失常和心源性猝死有关。在这里，我们鉴定了一种 hERG1 多肽 (hERG1NP)，它靶向未成熟心肌细胞的细胞核，包括人类干细胞衍生的心肌细胞 (hiPSC-CM) 和新生大鼠心肌细胞。成熟的 hiPSC-CM 中核 hERG1NP 免疫荧光信号减弱，成年大鼠心肌细胞中不存在。针对不同 hERG1 通道表位的抗体证明 hERG1NP 信号映射到 hERG1 远端 C 末端结构域。使用 CRISPR 删除 KCNH2 同时消除 hiPSC-CM 中的 IKr 和 hERG1NP 信号。然后，我们在远端 hERG1 C 末端内鉴定了一个推定的核定位序列 (NLS)，883-RQRKRKLSFR-892。有趣的是，当 HEK293 细胞过表达时，远端 C 端结构域几乎专门针对细胞核。相反，从远端肽中删除 NLS 就废除了核靶向。同样，阻断 α 或 β1 核转运蛋白活性会减弱核靶向作用。最后，与表达 NLS 缺陷的 hERG1NP 或 GFP 的细胞相比，在 HEK 细胞核中过表达假定的 hERG1NP 肽显着降低了 hERG1a 电流密度。这些数据鉴定了由 KCNH2、hERG1NP 编码的发育调节多肽，其存在于细胞核中间接调节 hERG1 电流大小和动力学。
KCNH2 encodes the voltage-gated potassium channel, hERG1. hERG1 variants are associated with sudden death in the young, including intrauterine fetal death, sudden infant death syndrome (SIDS), and sudden unexplained death in epilepsy (SUDEP). Here we identify a non-conducting KCNH2-encoded polypeptide, hERG1NP, that is upregulated in immature cardiomyocytes, and its targeting to the nucleus indirectly modulates hERG1 gating. These data identify a regulatory mechanism for hERG1 channels and could represent a therapeutic target for diseases related to hERG1 dysfunction. KCNH2 encodes hERG1, the voltage-gated potassium channel that conducts the rapid delayed rectifier potassium current (IKr) in human cardiac tissue. hERG1 is one of the first channels expressed during early cardiac development, and its dysfunction is associated with intrauterine fetal death, sudden infant death syndrome, cardiac arrhythmia, and sudden cardiac death. Here, we identified a hERG1 polypeptide (hERG1NP) that is targeted to the nuclei of immature cardiac cells, including human stem cell-derived cardiomyocytes (hiPSC-CMs) and neonatal rat cardiomyocytes. The nuclear hERG1NP immunofluorescent signal is diminished in matured hiPSC-CMs and absent from adult rat cardiomyocytes. Antibodies targeting distinct hERG1 channel epitopes demonstrated that the hERG1NP signal maps to the hERG1 distal C-terminal domain. KCNH2 deletion using CRISPR simultaneously abolished IKr and the hERG1NP signal in hiPSC-CMs. We then identified a putative nuclear localization sequence (NLS) within the distal hERG1 C-terminus, 883-RQRKRKLSFR-892. Interestingly, the distal C-terminal domain was targeted almost exclusively to the nuclei when overexpressed HEK293 cells. Conversely, deleting the NLS from the distal peptide abolished nuclear targeting. Similarly, blocking α or β1 karyopherin activity diminished nuclear targeting. Finally, overexpressing the putative hERG1NP peptide in the nuclei of HEK cells significantly reduced hERG1a current density, compared to cells expressing the NLS-deficient hERG1NP or GFP. These data identify a developmentally regulated polypeptide encoded by KCNH2, hERG1NP, whose presence in the nucleus indirectly modulates hERG1 current magnitude and kinetics.
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影响因子：
4.6
作者：
Block T;Creech J;da Rocha AM;Marinkovic M;Ponce-Balbuena D;Jiménez-Vázquez EN;Griffey S;Herron TJ
通讯作者：
Herron TJ
影响因子：
64.5
作者：
Cabral, JHM;Lee, A;Mackinnon, R
通讯作者：
Mackinnon, R
影响因子：
3.3
作者：
Cherubini, A;Hofmann, G;Arcangeli, A
通讯作者：
Arcangeli, A
影响因子：
5.5
作者：
Bannister, John P.;Leo, Marie Dennis;Jaggar, Jonathan H.
通讯作者：
Jaggar, Jonathan H.
影响因子：
3.7
作者：
Gomez-Ospina N;Panagiotakos G;Portmann T;Pasca SP;Rabah D;Budzillo A;Kinet JP;Dolmetsch RE
通讯作者：
Dolmetsch RE