Transport of soluble proteins through the Golgi occurs by diffusion via continuities across cisternae
- Fondazione IFOM, Italy
- Consiglio Nazionale Delle Ricerche (CNR-IBP), Italy
- Telethon Institute for Genetics and Medicine (TIGEM), Italy
- Consorzio Mario Negri Sud, Italy
- Center for Anatomy and Cell Biology, Medical University of Vienna, Austria
- FEI Company, Netherlands
- Saarland University, Germany
Abstract
The mechanism of transport through the Golgi complex is not completely understood, insofar as no single transport mechanism appears to account for all of the observations. Here, we compare the transport of soluble secretory proteins (albumin and α1-antitrypsin) with that of supramolecular cargoes (e.g., procollagen) that are proposed to traverse the Golgi by compartment progression-maturation. We show that these soluble proteins traverse the Golgi much faster than procollagen while moving through the same stack. Moreover, we present kinetic and morphological observations that indicate that albumin transport occurs by diffusion via intercisternal continuities. These data provide evidence that this transport mechanism that applies to a major class of secretory proteins and indicate the co-existence of multiple intra-Golgi trafficking modes.
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© 2014, Beznoussenko et al.
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Transport of soluble proteins through the Golgi occurs by diffusion via continuities across cisternae
eLife 3:e02009.
https://doi.org/10.7554/eLife.02009
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