Cytoplasmic Ca²⁺ is a pivotal regulator of IP₃R activity. It is however controversial whether the [Ca²⁺] in the Endoplasmic Reticulum lumen also directly regulates channel function. We highlight a recent paper that demonstrates that luminal [Ca²⁺] potently inhibits IP₃R activity. This regulation occurs indirectly by an interaction mediated through a binding partner, likely Annexin 1A.

中文翻译：

---

内部工作：膜联蛋白 1A-肌醇 1,4,5-三磷酸受体相互作用传达内质网腔 Ca2+ 敏感性。

细胞质 Ca ²⁺是 IP ₃ R 活性的关键调节剂。然而，内质网腔中的[Ca ²⁺ ]是否也直接调节通道功能存在争议。我们重点介绍了最近的一篇论文，该论文证明 luminal [Ca ²⁺ ] 有效抑制 IP ₃ R 活性。这种调节是通过结合伴侣（可能是膜联蛋白 1A）介导的相互作用间接发生的。