Abstract

Mechanically gated cation channels that are activated upon deformation of the membrane are key participants in the transmission of mechanical signals from the cell surface to cytoplasmic structures. It has remained unclear how mechanically dependent reactions involving ion channels in native cells are realized. In this study, we analyzed the development of the activity of single channels in K562 human myeloid leukemia cells in response to the delivery of a mechanical stimulus, this being stretching of the membrane area. The registration of ion currents using the classic versions of the patch–clamp method allowed revealing the functional clustering and interaction of various types of channels in the plasma membrane during mechanotransduction. In K562 cells, coupled activation of mechanosensitive calcium-conducting channels and calcium-activated potassium channels was detected. Real-time recordings of currents demonstrate that the calcium influx from the extracellular medium into the cytoplasm through mechanically gated channels activates potassium channels that are colocalized with them, which do not have their own mechanosensitivity. In experiments on K562 cells and transformed 3T3-SV40 fibroblasts, the preservation of the functional conjugation of the channels during their mechanically gated activation after the action of the microfilament destructor cytochalasin D was shown. The results suggest that clusters including potassium SK channels and Piezo1/2 proteins forming stretch-activated cation channels function in the plasma membrane of K562 and 3T3-SV40 cells.

中文翻译：

---

离子通道在K562细胞膜上的机械依赖性激活过程中的功能耦合。

摘要

在膜变形时被激活的机械门控阳离子通道是从细胞表面到细胞质结构的机械信号传递的关键参与者。尚不清楚如何实现涉及天然细胞中离子通道的机械依赖性反应。在这项研究中，我们分析了K562人髓样白血病细胞中单通道活性的发展，以响应机械刺激的传递，这是膜区域的伸展。使用经典的膜片钳方法对离子电流进行配准，可以揭示机械转导过程中质膜中各种类型通道的功能聚集和相互作用。在K562细胞中 检测到机械敏感的钙传导通道和钙激活的钾通道的偶联激活。电流的实时记录表明，钙通过机械门控通道从细胞外培养基流入细胞质激活了与其共同定位的钾通道，而钾通道却没有自身的机械敏感性。在针对K562细胞和转化的3T3-SV40成纤维细胞的实验中，显示了在微丝破坏因子细胞松弛素D作用后，通道在其机械门控激活过程中的功能缀合得以保留。结果表明，包括钾SK通道和形成拉伸激活阳离子通道的Piezo1 / 2蛋白的簇在K562和3T3-SV40细胞的质膜中起作用。电流的实时记录表明，钙通过机械门控通道从细胞外培养基流入细胞质激活了与其共同定位的钾通道，而钾通道却没有自身的机械敏感性。在针对K562细胞和转化的3T3-SV40成纤维细胞的实验中，显示了在微丝破坏因子细胞松弛素D作用后，通道在其机械门控激活过程中的功能缀合得以保留。结果表明，包括钾SK通道和形成拉伸激活阳离子通道的Piezo1 / 2蛋白的簇在K562和3T3-SV40细胞的质膜中起作用。电流的实时记录表明，钙通过机械门控通道从细胞外培养基流入细胞质激活了与其共同定位的钾通道，而钾通道却没有自身的机械敏感性。在针对K562细胞和转化的3T3-SV40成纤维细胞的实验中，显示了在微丝破坏因子细胞松弛素D作用后，通道在其机械门控激活过程中的功能缀合得以保留。结果表明，包括钾SK通道和形成拉伸激活阳离子通道的Piezo1 / 2蛋白的簇在K562和3T3-SV40细胞的质膜中起作用。