Stress granules (SGs) are stress-induced membraneless condensates that store non-translating mRNA and stalled translation initiation complexes. Although metazoan SGs are dynamic compartments where proteins can rapidly exchange with their surroundings, yeast SGs seem largely static. To gain a better understanding of yeast SGs, we identified proteins that sediment after heat shock using mass spectrometry. Proteins that sediment upon heat shock are biased toward a subset of abundant proteins that are significantly enriched in intrinsically disordered regions (IDRs). Heat-induced SG localization of over 80 proteins were confirmed using microscopy, including 32 proteins not previously known to localize to SGs. We found that several IDRs were sufficient to mediate SG recruitment. Moreover, the dynamic exchange of IDRs can be observed using fluorescence recovery after photobleaching, whereas other components remain immobile. Lastly, we showed that the IDR of the Ubp3 deubiquitinase was critical for yeast SG formation. This work shows that IDRs can be sufficient for SG incorporation, can remain dynamic in vitrified SGs, and can play an important role in cellular compartmentalization upon stress.

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应激颗粒 (SG) 是应激诱导的无膜缩合物，可储存非翻译 mRNA 和停滞的翻译起始复合物。尽管后生动物 SG 是动态的隔室，其中蛋白质可以与周围环境快速交换，但酵母 SG 似乎基本上是静态的。为了更好地了解酵母 SG，我们使用质谱法鉴定了热休克后沉积的蛋白质。热激时沉积的蛋白质偏向于在本质无序区域 (IDR) 中显着富集的丰富蛋白质的子集。使用显微镜证实了 80 多种蛋白质的热诱导 SG 定位，其中包括 32 种以前未知的 SG 定位蛋白质。我们发现几个 IDR 足以介导 SG 招募。此外，可以使用光漂白后的荧光恢复来观察 IDR 的动态交换，而其他组分则保持不动。最后，我们表明 Ubp3 去泛素酶的 IDR 对于酵母 SG 的形成至关重要。这项工作表明，IDR 足以掺入 SG，可以在玻璃化 SG 中保持动态，并且可以在应激时的细胞区室化中发挥重要作用。

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