Institut de Biologie François Jacob, Molecular Imaging Research Center (MIRCen), Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Direction de la Recherche Fondamentale (DRF), Laboratoire des Maladies Neurodégénératives, Centre National de la Recherche Scientifique (CNRS), Fontenay-aux-Roses, France.
Mol Microbiol. 2020 Aug;114(2):322-332. doi: 10.1111/mmi.14515. Epub 2020 May 8.
The yeast [PSI ] prion originates from the self-perpetuating transmissible aggregates of the translation termination factor Sup35p. We previously showed that infectious Sup35p particles are exported outside the cells via extracellular vesicles (EV). This finding suggested a function for EV in the vertical and horizontal transmission of yeast prions. Here we report a significant export of Sup35p within periplasmic vesicles (PV) upon glucose starvation. We show that PV are up to three orders of magnitude more abundant than EV. However, PV and EV are different in terms of size and protein content, and their export is oppositely regulated by glucose availability in the growth medium. Overall, our work suggests that the export of prion particles to both the periplasm and the extracellular space needs to be considered to address the physiological consequences of vesicle-mediated yeast prions trafficking.
酵母 [PSI ] 朊病毒源自自我维持的可传播翻译终止因子 Sup35p 的聚集物。我们之前的研究表明，传染性 Sup35p 颗粒通过细胞外囊泡 (EV) 被运出细胞。这一发现表明囊泡在酵母朊病毒的垂直和水平传播中具有功能。在这里，我们报告了在葡萄糖饥饿时，周质小泡 (PV) 中 Sup35p 的大量输出。我们表明，PV 的丰度比 EV 高三个数量级。然而，PV 和 EV 在大小和蛋白质含量方面存在差异，它们的输出受到生长培养基中葡萄糖可用性的反向调节。总的来说，我们的工作表明，需要考虑到朊病毒颗粒向周质和细胞外空间的输出，以解决囊泡介导的酵母朊病毒运输的生理后果。
