Endoplasmic reticulum (ER)-associated degradation (ERAD) plays an essential role in protein quality control in the ER. It acts through recognizing misfolded or unassembled proteins and retrotranslocating them across the ER membrane into the cytosol for degradation. ER-phagy, which is an ERAD pathway, also controls the quality and abundance of proteins and organelles by activating ER-resident receptors. ER membrane is the important site of initiation for phagophores (crescent-shaped membranes that form and mature into autophagosomes); however, specific sites that are restricted on ER during ER-phagy remain to be identified. Recently, Cui et al. [1] found that a COPII coat subunit, Lst1/SEC24C-Sec23, plays an unconventional role in targeting ER domains for degradation of the ER-phagy receptor, which makes them essential to ER-phagy. In yeast, the COPII-cargo adaptor complex Lst1-Sec23 co-localizes with up-regulated ER-phagy receptor Atg40 (FAM134B in mammals) to sort ER domains into autophagosomes during ER-phagy, eventually leading to the reduction of protein aggregation in ER. In mammals, the formation of Lst1/SEC24C-Sec23 is required for the degradation of two mammalian ER-phagy receptors, FAM134B and RTN3. They concluded that the COPII subunit Lst1/SEC24C-Sec23 functions with ER-phagy receptors to package ER domains for degradation, thereby reducing protein aggregation and preserving cellular health [1].

中文翻译：

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COPII亚基与ER吞噬受体相互作用：维持神经元稳态的新潜在途径。

内质网（ER）相关降解（ERAD）在ER中蛋白质质量控​​制中起着重要作用。它的作用是识别错误折叠或未组装的蛋白质，然后将它们跨过ER膜逆向转运至细胞质中进行降解。ER吞噬是一种ERAD途径，它还可以通过激活ER驻留受体来控制蛋白质和细胞器的质量和丰度。内质网膜是吞噬细胞（形成并成熟为自噬体的新月形膜）的重要起始位点。但是，在ER吞噬过程中受ER限制的特定位点仍有待确定。最近，崔等人。[1]发现COPII外壳亚基Lst1 / SEC24C-Sec23在靶向ER域以降解ER-噬菌体受体方面发挥非常规作用，这使其成为ER-噬菌体必不可少的。在酵母中，COPII货物衔接子复合体Lst1-Sec23与上调的ER-吞噬受体Atg40（在哺乳动物中为FAM134B）共定位，以在ER-吞噬过程中将ER结构域分类为自噬体，最终导致ER中的蛋白质聚集减少。在哺乳动物中，Lst1 / SEC24C-Sec23的形成是降解两种哺乳动物ER吞噬受体FAM134B和RTN3所必需的。他们得出的结论是，COPII亚基Lst1 / SEC24C-Sec23与ER吞噬受体一起起作用，包装ER结构域以进行降解，从而减少蛋白质聚集并保持细胞健康[1]。