Autor: |
Uemura, Tomohiro, Nakano, Ryohei Thomas, Takagi, Junpei, Wang, Yiming, Kramer, Katharina, Finkemeier, Iris, Nakagami, Hirofumi, Tsuda, Kenichi, Ueda, Takashi, Schulze-Lefert, Paul, Nakano, Akihiko |
Jazyk: |
angličtina |
Rok vydání: |
2018 |
Předmět: |
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Popis: |
Spatiotemporal coordination of protein trafficking among organelles is essential for eukaryotic cells. The post-Golgi interface, including the trans-Golgi network (TGN), is a pivotal hub for multiple trafficking pathways. The Golgi-released independent TGN (GI-TGN) is a compartment described only in plant cells, and its cellular and physiological roles remain elusive. In Arabidopsis (Arabidopsis thaliana), the SYNTAXIN OF PLANTS (SYP) 4 group Qa-SNARE (soluble N-ethylmaleimide) membrane fusion proteins are shared components of TGN and GI-TGN and regulate secretory and vacuolar transport. Here we reveal that GI-TGNs mediate the transport of the R-SNARE VESICLE-ASSOCIATED MEMBRANE PROTEIN (VAMP) 721 to the plasma membrane. In interactions with a nonadapted powdery mildew pathogen, the SYP4 group of SNAREs is required for the dynamic relocation of VAMP721 to plant–fungus contact sites via GI-TGNs, thereby facilitating complex formation with its cognate SNARE partner PENETRATION1 to restrict pathogen entry. Furthermore, quantitative proteomic analysis of leaf apoplastic fluid revealed constitutive and pathogen-inducible secretion of cell wall-modification enzymes in a SYP4- and VAMP721-dependent manner. Hence, the GI-TGN acts as a transit compartment between the Golgi apparatus and the plasma membrane. We propose a model in which the GA-TGN matures into the GI-TGN and then into secretory vesicles by increasing the abundance of VAMP721-dependent secretory pathway components. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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