Heat causes oligomeric disassembly and increases the chaperone activity of small heat shock proteins from sugarcane.
Heat causes oligomeric disassembly and increases the chaperone activity of small heat shock proteins from sugarcane.
复制标题
热量会导致寡聚体分解，并增加甘蔗中小热休克蛋白的伴侣活性。
DOI：
10.1016/j.plaphy.2010.01.001
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Ramos,CarlosHI
中科院分区：
文献类型：
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作者：
Tiroli-Cepeda,AnaO;Ramos,CarlosHI
小分子热休克蛋白(SHSP)是与构象疾病相关的一个重要的伴侣蛋白家族。在植物中，sHSPs通过作为温度传感器来阻止蛋白质聚集，并增强细胞的逆境耐受性。SsHsp17.2和SsHsp17.9是甘蔗中表达最高的I类sHsps。它们在20℃时以十二聚体的形式存在，并具有明显的底物特性。因此，它们是研究I类SHSP如何工作的有用模型。在这里，我们提供了关于加热对SsHsp17.2和SsHsp17.9的齐聚和伴侣活性的影响的数据。使用几个生物物理和生化探针，我们证明了热的影响是完全可逆的，这是作用于热休克温度的蛋白质的一个重要性质。SsHsp17.2和SsHsp17.9十二聚体在40~45℃的温度下解离成二聚体，解离之后伴随着伴侣活性的增强。我们的结论是，高温影响这些伴侣的低聚状态，导致伴侣活性增强。
Small heat shock proteins (sHsp) constitute an important chaperone family linked to conformational diseases. In plants, sHsps prevent protein aggregation by acting as thermosensors and to enhance cell stress tolerance. SsHsp17.2 and SsHsp17.9 are the most highly expressed class I sHsps in sugarcane. They exist as dodecamers at 20 °C and have distinct substrate specificities. Therefore, they are useful models to study how class I SHsps work. Here we present data on the effects of heat on the oligomerization and chaperone activity of SsHsp17.2 and SsHsp17.9. Using several biophysical and biochemical probes, we show that the effects of heat are completely reversible, an important property for proteins that act at heat shock temperatures. SsHsp17.2 and SsHsp17.9 dodecamers dissociated to dimers at temperatures ranging from 40 to 45 °C and this dissociation was followed by enhanced chaperone activity. We conclude that high temperature affects the oligomeric state of these chaperones, resulting in enhanced chaperone activity.