Tudor staphylococcal nuclease (TSN; also known as Tudor-SN, p100, or SND1) is a multifunctional, evolutionarily conserved regulator of gene expression, exhibiting cytoprotective activity in animals and plants and oncogenic activity in mammals. During stress, TSN stably associates with stress granules (SGs), in a poorly understood process. Here, we show that in the model plant Arabidopsis thaliana, TSN is an intrinsically disordered protein (IDP) acting as a scaffold for a large pool of other IDPs, enriched for conserved stress granule components as well as novel or plant-specific SG-localized proteins. While approximately 30% of TSN interactors are recruited to stress granules de novo upon stress perception, 70% form a protein–protein interaction network present before the onset of stress. Finally, we demonstrate that TSN and stress granule formation promote heat-induced activation of the evolutionarily conserved energy-sensing SNF1-related protein kinase 1 (SnRK1), the plant orthologue of mammalian AMP-activated protein kinase (AMPK). Our results establish TSN as a docking platform for stress granule proteins, with an important role in stress signalling.

中文翻译：

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Tudor 葡萄球菌核酸酶是应激颗粒成分的对接平台，对于拟南芥中 SnRK1 的激活至关重要


Tudor 葡萄球菌核酸酶（TSN；也称为 Tudor-SN、p100 或 SND1）是一种多功能、进化上保守的基因表达调节因子，在动物和植物中表现出细胞保护活性，在哺乳动物中表现出致癌活性。在压力期间，TSN 与压力颗粒 (SG) 稳定地结合在一起，但这一过程尚不清楚。在这里，我们表明，在模型植物拟南芥中，TSN 是一种本质上无序的蛋白质 (IDP)，充当大量其他 IDP 的支架，富含保守的应激颗粒成分以及新颖或植物特异性 SG 本地化蛋白质。虽然大约 30% 的 TSN 相互作用因子在压力感知时被重新招募到应激颗粒中，但 70% 的 TSN 相互作用因子在压力发生前形成蛋白质-蛋白质相互作用网络。最后，我们证明 TSN 和应激颗粒的形成促进了进化上保守的能量感应 SNF1 相关蛋白激酶 1 (SnRK1) 的热诱导激活，SnRK1 是哺乳动物 AMP 激活蛋白激酶 (AMPK) 的植物直系同源物。我们的结果确立了 TSN 作为应激颗粒蛋白的对接平台，在应激信号传导中发挥着重要作用。