Passive diffusion accounts for the majority of intracellular vesicle transport
Passive diffusion accounts for the majority of intracellular vesicle transport
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被动扩散占细胞内囊泡运输的大部分
DOI：
10.1101/2023.05.10.540182
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Sittewelle M
中科院分区：
文献类型：
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作者：
Sittewelle M
在膜运输过程中，在供体隔室形成的囊泡必须在融合之前到达受体膜。对于大型运输船，已经确定这种运输是由电动机驱动的；然而，小囊泡的运输方式，其数量超过较大的载体，是缺乏表征的。在这里，我们发现细胞内纳米囊泡（INVs）是一大类小囊泡，在细胞内具有高度的流动性，并且这种流动性几乎完全取决于被动扩散（0.1-0.3µm2s−1）。使用单粒子跟踪，我们描述了其他小运输囊泡如何具有类似的扩散运输模式，这与较大的内溶酶体载体的运动依赖运动形成对比。我们还证明了一组INVs参与了本构分泌，并且当INVs的扩散受到特别限制时，胞吐过程中向质膜输送的货物减少。我们的研究结果表明，被动扩散足以解释大多数小泡运输。
During membrane trafficking, a vesicle formed at the donor compartment must travel to the acceptor membrane before fusing. For large carriers, it is established that this transport is motor-driven; however, the mode by which small vesicles, which outnumber larger carriers, are transported is poorly characterized. Here we show that intracellular nanovesicles (INVs), a substantial class of small vesicles, are highly mobile within cells and that this mobility depends almost entirely on passive diffusion (0.1–0.3 µm2s−1). Using single particle tracking, we describe how other small trafficking vesicles have a similar diffusive mode of transport, that contrasts with the motor-dependent movement of larger endolysosomal carriers. We also demonstrate that a subset of INVs are involved in constitutive secretion and that delivery of cargo to the plasma membrane during exocytosis is decreased when diffusion of INVs is specifically restricted. Our results suggest that passive diffusion is sufficient to explain the majority of small vesicle transport.