ATP is stored in lysosomes of greater epithelial ridge supporting cells in newborn rat cochleae
ATP is stored in lysosomes of greater epithelial ridge supporting cells in newborn rat cochleae
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ATP储存在新生大鼠耳蜗大上皮嵴支持细胞的溶酶体中
DOI：
10.1002/jcb.29251
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发表时间：
2019-07-02
影响因子：
4
通讯作者：
Yang, Jun
中科院分区：
文献类型：
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作者：
Chen, Jiarui;Hou, Shule;Yang, Jun
三磷酸腺苷 (ATP) 在耳蜗的发育和成熟中发挥着至关重要的作用，由大鼠耳蜗的大上皮脊 (GER) 支持细胞释放，但储存 ATP 的细胞器尚未确定。因此，我们研究了参与 ATP 储存的细胞器，并表明溶酶体提供了这种功能。分离、纯化和培养新生大鼠的GER支持细胞，并通过共聚焦显微镜和透射电子显微镜（TEM）鉴定支持细胞内的标记囊泡。测量甘氨酰-L-苯丙氨酸-β-萘酰胺 (GPN) 处理后 GER 支持细胞释放的 ATP。共聚焦显微镜和TEM观察到的特异性标记细胞器是溶酶体，GPN处理增强了支持细胞胞外液中的ATP发光。支持细胞释放 ATP 受到细胞内和细胞外 Ca2+ 浓度变化的影响。此外，抑制磷脂酶信号通路引起的细胞内Ca2+变化影响了支持细胞ATP的释放。我们证明，ATP 储存在新生大鼠耳蜗内 GER 支持细胞的溶酶体中，并且 GER 支持细胞释放的 ATP 可能是 Ca2+ 依赖性的。
Adenosine triphosphate (ATP), which plays a crucial role in both developing and mature cochleae, is released from greater epithelial ridge (GER) supporting cells of the rat cochlea, but the organelles in which ATP is stored have not yet been identified. Thus, we studied the organelles involved in ATP storage and suggest that lysosomes provide this function. GER supporting cells of newborn rats were isolated, purified, and cultured, and labeled vesicles within the supporting cells were identified via confocal microscopy and transmission electron microscopy (TEM). ATP release from GER supporting cells after glycyl‐L‐phenylalanine‐β‐naphthylamide (GPN) treatment was measured. The specifically labeled organelles observed by confocal microscopy and TEM were lysosomes, and GPN treatment enhanced ATP luminescence in the extracellular fluid of the supporting cells. The release of ATP from supporting cells was affected by changes in intra‐ and extracellular Ca2+ concentrations. In addition, changes in the intracellular Ca2+ caused by inhibiting the phospholipase signaling pathway affected the release of ATP from supporting cells. We demonstrated that ATP is stored in the lysosomes of GER supporting cells within newborn rat cochleae and that ATP release from GER supporting cells may be Ca2+‐dependent.