膜联蛋白 A3：新发现的钙库操纵性钙内流的参与者。

Annexin A3: a newly identified player in store‑operated calcium entry.

机构信息

Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, Poland.

Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, Poland;

出版信息

Acta Neurobiol Exp (Wars). 2021;81(4):307-313.

Abstract

Store‑operated calcium entry (SOCE) is important for refilling endoplasmic reticulum (ER) Ca2+ stores and Ca2+ signaling. Extracellular Ca2+ is conducted by highly Ca2+‑selective Orai channels that are activated by stromal interaction molecule proteins (STIMs), which are sensitive ER Ca2+ sensors. We found an approximately five‑fold increase in annexin A3a (anxa3a) expression levels in stim2b knockout zebrafish. The present study investigated whether annexin A3 protein is involved in SOCE. We used Ca2+ imaging and electrophysiological recordings to determine the effect of annexin A2, A3, and A6 overexpression on SOCE and Orai-dependent Ca2+ currents (ICRAC) in cultured cells. Annexin A3 increased SOCE amplitude and potentiated Ca2+ ICRAC currents. These results suggest that annexin A3 is a positive modulator of SOCE.

摘要

钙库操纵性钙内流（SOCE）对于内质网（ER）Ca2+ 储存和 Ca2+ 信号转导非常重要。细胞外 Ca2+ 通过高度 Ca2+ 选择性的 Orai 通道进行传导，该通道由基质相互作用分子蛋白（STIMs）激活，而 STIMs 是 ER Ca2+ 传感器。我们发现，在 stim2b 基因敲除斑马鱼中， annexin A3a（anxa3a）的表达水平增加了约五倍。本研究探讨了 annexin A3 蛋白是否参与 SOCE。我们使用 Ca2+ 成像和电生理记录来确定 annexin A2、A3 和 A6 过表达对培养细胞中 SOCE 和 Orai 依赖性 Ca2+ 电流（ICRAC）的影响。Annexin A3 增加了 SOCE 的幅度并增强了 Ca2+ ICRAC 电流。这些结果表明 annexin A3 是 SOCE 的正调节剂。