The endoplasmic reticulum (ER) consists of the nuclear envelope and a reticulated interconnected network of tubules and sheets. ER sheets are studded with ribosomes and provide the entryway for proteins into the secretory pathway. ER tubules move dynamically on microtubules and form membrane contact sites with other organelles, where membranes are tethered, but not fused. This Snapshot reviews key biological processes that take place at ER contact sites with the Golgi, endosomes, and mitochondria.

中文翻译：

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快照：内质网膜接触部位的功能。

内质网（ER）由核包膜和细管和薄片的网状互连网络组成。ER片上缀有核糖体，为蛋白质进入分泌途径提供了途径。ER小管在微管上动态移动，并与其他细胞器形成膜接触部位，在这些细胞器中，膜被束缚但未融合。本快照回顾了在高尔基体，内体和线粒体与内质网接触的部位发生的关键生物学过程。