MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK.
Biochim Biophys Acta Mol Cell Biol Lipids. 2020 Jan;1865(1):158492. doi: 10.1016/j.bbalip.2019.07.001. Epub 2019 Jul 23.
The endoplasmic reticulum (ER) is a highly organized organelle that performs vital functions including de novo membrane lipid synthesis and transport. Accordingly, numerous lipid biosynthesis enzymes are localized in the ER membrane. However, it is now evident that lipid metabolism is sub-compartmentalized within the ER and that lipid biosynthetic enzymes engage with lipid transfer proteins (LTPs) to rapidly shuttle newly synthesized lipids from the ER to other organelles. As such, intimate relationships between lipid metabolism and lipid transfer pathways exist within the ER network. Notably, certain LTPs enhance the activities of lipid metabolizing enzymes; likewise, lipid metabolism can ensure the specificity of LTP transfer/exchange reactions. Yet, our understanding of these mutual relationships is still emerging. Here, we highlight past and recent key findings on specialized ER membrane domains involved in efficient lipid metabolism and transport and consider unresolved issues in the field.
内质网（ER）是一种高度组织化的细胞器，具有许多重要的功能，包括从头合成膜脂和运输。相应地，许多脂质生物合成酶都定位于 ER 膜上。然而，现在很明显，脂质代谢在 ER 中是亚区室化的，脂质生物合成酶与脂质转移蛋白（LTP）结合，快速将新合成的脂质从 ER 转运到其他细胞器。因此，ER 网络中存在着脂质代谢和脂质转移途径之间的密切关系。值得注意的是，某些 LTP 可以增强脂质代谢酶的活性；同样，脂质代谢可以确保 LTP 转移/交换反应的特异性。然而，我们对这些相互关系的理解仍在不断发展。在这里，我们重点介绍过去和最近在涉及高效脂质代谢和运输的 ER 膜域方面的关键发现，并考虑该领域尚未解决的问题。
