Elsner Markus, Hashimoto Hitoshi, Nilsson Tommy
Cell Biology Programme, EMBL, Meyerhofstrasse 1, D-690117, Heidelberg, Germany.
Mol Membr Biol. 2003 Jul-Sep;20(3):221-9. doi: 10.1080/0968768031000114024.
'No cellular organelle has been the subject of as many, as long-lasting or as diverse polemics as the Golgi apparatus'. This statement was made by Whaley almost 30 years ago in the book The Golgi Apparatus and still holds true today, perhaps more then ever. Why is this? How come something as mundane as a series of intracellular membrane bound structures continues to fascinate and captivate a large section of the cell biology community? One simple reason (putting polemics aside) is that the secretory pathway appears deceptively simple. Once probed, however, it has a persistent habit of developing into an enigma. Is one then not closer than 30 years ago? In a sense yes, in that one has more components and a better understanding of inherent membrane dynamics, but it is still not known how newly synthesized proteins and lipids make their way from the ER to the plasma membrane. Is it by vesicles, cisternal carriers or transient tubular connections? It has also been learned that newly synthesized proteins are segregated away from the resident components throughout the pathway, but not how. Do coat proteins hold the key? It is understood that the cytoskeleton is important, but not really why. It is known that each Golgi stack is a fully functional unit, but not why stacks are connected laterally into a large ribbon (the Golgi apparatus). This review focuses on how proteins make their way through the pathway, a basic question that remains to be answered.
“没有哪个细胞器像高尔基体那样引发如此众多、持久且多样的争论”。这句话是惠利近30年前在《高尔基体》一书中说的，时至今日依然正确，或许比以往任何时候都更适用。这是为什么呢？像一系列细胞内膜结合结构这样平常的东西，怎么会持续吸引并迷住细胞生物学界的很大一部分人呢？一个简单的原因（暂且不谈争论）是分泌途径看似简单得具有欺骗性。然而，一旦深入探究，它就总是会演变成一个谜。那么现在比30年前更接近真相了吗？从某种意义上说，是的，因为现在有了更多的组成部分，对内在膜动力学也有了更好的理解，但仍然不知道新合成的蛋白质和脂质是如何从内质网到达质膜的。是通过囊泡、扁平囊泡载体还是瞬时管状连接呢？人们还了解到新合成的蛋白质在整个途径中都与驻留成分分开，但不知道是如何分开的。是包被蛋白起着关键作用吗？人们知道细胞骨架很重要，但不清楚真正原因。人们知道每个高尔基体堆叠都是一个功能完备的单位，但不知道为什么堆叠会横向连接成一个大的带状结构（高尔基体）。这篇综述聚焦于蛋白质如何在这条途径中移动，这是一个有待解答的基本问题。
