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bioRxiv · 10.1101/2024.07.02.601695

TORC1-containing signaling endosomes source membrane from vacuoles

Muneshige, K.·Hatakeyama, R.
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Abstract

Organelle biogenesis is fundamental to eukaryotic cell biology. Yeast signaling endosomes were recently identified as a signaling platform for the evolutionarily conserved Target of Rapamycin Complex 1 (TORC1) kinase complex. Despite the importance of signaling endosomes for TORC1-mediated control of cellular metabolism, how this organelle is generated has been a mystery. Here, we developed a system to induce synchronized de novo formation of signaling endosomes, enabling real-time monitoring of their biogenesis. Using this system, we identify vacuoles as a membrane source for newly formed signaling endosomes. Membrane supply from vacuoles is mediated by the CROP membrane-cutting complex, consisting of Atg18 PROPPIN and retromer subunits. The formation of signaling endosomes requires TORC1 activity, suggestive of a tightly regulated process. This study unveiled the first mechanistic principles and molecular participants of signaling endosome biogenesis. SummaryMembrane is supplied by vacuoles during biogenesis of yeast signaling endosomes, in a process mediated by the membrane-cutting CROP complex and promoted by TORC1 kinase activity.

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Muneshige, K., Hatakeyama, R.. 2024-07-03. TORC1-containing signaling endosomes source membrane from vacuoles. https://doi.org/10.1101/2024.07.02.601695

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