Supplementary materials for "Morpho-functional characterisation of membrane carriers operating in post-Golgi transport routes"

This dataset comprises the contents of a CD-ROM which was attached to the thesis when it was submitted in 2005. It was uploaded to ORDO in 2024, for preservation purposes. For more information, please refer to "Morpho-functional characterisation of membrane carriers operating in post-Golgi transport routes" on ORO.Thesis abstractTransport of constitutive cargo proteins from the Golgi complex to the plasma membrane (PM) is known to be mediated by large tubular-saccular carriers moving along microtubules. However, the process by which these large structures emerge from the trans-Golgi network (TGN) remains unclear. The formation of Golgi-to-PM carriers (GPCs) has been investigated in the present study by using a suitable cluster of morphological techniques, providing an integrated view of GPC dynamics and three-dimensional structure. The results obtained indicate that exit from the TGN of a constitutive traffic marker, the VSVG protein, occurs by bulk flow and is a three-step process. First, the formation of a tubular-reticular TGN domain (GPC precursor) that includes PM-directed proteins and excludes other cargo and Golgi-resident proteins. Notably, this step does not require membrane fusion. Second, the docking of this preformed domain on microtubules and its kinesin-mediated extrusion. Finally, the detachment of the extruded domain by membrane fission. The formation of GPCs does not involve cargo concentration and is not associated with the presence of known coat proteins on GPC precursors. In summary, export from the Golgi occurs via the formation, protrusion and en bloc cleavage of specialized TGN tubular-saccular domains.

本数据集收录了2005年提交的论文所附CD-ROM的内容。该数据集于2024年上传至ORDO，旨在进行长期保存。欲了解更多信息，请参阅ORO论文摘要《膜转运载体在Golgi体后运输途径中的形态功能特性》。已知构成性货物蛋白从高尔基体复合物向质膜（PM）的转运过程是由沿着微管移动的大型管状-泡状载体介导的。然而，这些大型结构如何从转运高尔基体网络（TGN）中产生的过程尚不明确。本研究通过采用适宜的形态学技术群，对高尔基体至质膜载体（GPCs）的形成进行了研究，从而提供了GPC动态和三维结构的综合视角。所得结果表明，构成性交通标记物VSVG蛋白从TGN的排出是通过整体流动实现的，并且是一个三步过程。首先，形成包括指向质膜蛋白且排除其他货物和高尔基体居民蛋白的管状-网状TGN区域（GPC前体），此步骤无需膜融合。其次，该预形成的区域在微管上的对接及其由肌球蛋白介导的排出。最后，通过膜裂解使排出区域脱落。GPCs的形成不涉及货物浓缩，且与已知衣蛋白在GPC前体上的存在无关。总之，高尔基体的输出是通过形成、突出和整体切割专门的TGN管状-泡状区域来实现的。