Cotto J, Fox S, Morimoto R
Department of Biochemistry, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208, USA.
J Cell Sci. 1997 Dec;110 ( Pt 23):2925-34. doi: 10.1242/jcs.110.23.2925.
Heat shock factor 1 (HSF1) is the ubiquitous stress-responsive transcriptional activator which is essential for the inducible transcription of genes encoding heat shock proteins and molecular chaperones. HSF1 localizes within the nucleus of cells exposed to heat shock, heavy metals, and amino acid analogues, to form large, irregularly shaped, brightly staining granules which are not detected during attenuation of the heat shock response or when cells are returned to their normal growth conditions. The kinetics of detection of HSF1 granules parallels the transient induction of heat shock gene transcription. HSF1 granules are also detected using an HSF1-Flag epitope tagged protein or a chimeric HSF1-green fluorescent protein which reveals that these nuclear structures are stress-induced and can be detected in living cells. The spatial organization of HSF1 granules in nuclei of stressed cells reveals that they are novel nuclear structures which are stress-dependent and provides evidence that the nucleus undergoes dynamic reorganization in response to stress.
热休克因子1（HSF1）是一种普遍存在的应激反应转录激活因子，对于编码热休克蛋白和分子伴侣的基因的诱导转录至关重要。HSF1定位于暴露于热休克、重金属和氨基酸类似物的细胞的细胞核内，形成大的、形状不规则、染色明亮的颗粒，在热休克反应减弱期间或细胞恢复到正常生长条件时未检测到这些颗粒。HSF1颗粒的检测动力学与热休克基因转录的瞬时诱导平行。使用HSF1-Flag表位标签蛋白或嵌合HSF1-绿色荧光蛋白也可检测到HSF1颗粒，这表明这些核结构是应激诱导的，并且可以在活细胞中检测到。应激细胞细胞核中HSF1颗粒的空间组织表明它们是新型的核结构，其依赖于应激，并提供了细胞核响应应激而发生动态重组的证据。
