The P2X4 receptor (P2X4R) is an ATP‐gated cation channel. Here, we used fast‐scan atomic force microscopy (AFM) to visualize changes in the structure and mobility of individual P2X4Rs in response to activation. P2X4Rs were purified from detergent extracts of transfected cells and integrated into lipid bilayers. Activation resulted in a rapid (2 s) and substantial (10–20 nm2) increase in the cross‐sectional area of the extracellular region of the receptor and a corresponding decrease in receptor mobility. Both effects were blocked by the P2X4R antagonist 5‐BDBD. Addition of cholesterol to the bilayer reduced receptor mobility, although the ATP‐induced reduction in mobility was still observed. We suggest that the observed responses to activation may have functional consequences for purinergic signalling.

中文翻译：

---

P2X4 受体的激活诱导细胞外区域面积的增加和受体迁移率的降低

P2X4 受体 (P2X4R) 是一种 ATP 门控阳离子通道。在这里，我们使用快速扫描原子力显微镜 (AFM) 来可视化响应激活的单个 P2X4R 的结构和迁移率变化。P2X4Rs 从转染细胞的去污剂提取物中纯化并整合到脂质双层中。激活导致受体细胞外区域的横截面积快速（2 s）和实质性（10-20 nm2）增加，受体迁移率相应降低。这两种作用都被 P2X4R 拮抗剂 5-BDBD 阻断。向双层中添加胆固醇降低了受体的迁移率，尽管仍观察到 ATP 诱导的迁移率下降。我们建议观察到的对激活的反应可能对嘌呤能信号传导产生功能影响。