Ishikawa Yukio, Kawabata Shotaro, Sakurai Hiroshi
Division of Health Sciences, Kanazawa University Graduate School of Medical Science, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 920-0942, Japan.
Division of Health Sciences, Kanazawa University Graduate School of Medical Science, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 920-0942, Japan.
FEBS Lett. 2015 Apr 28;589(10):1150-5. doi: 10.1016/j.febslet.2015.03.019. Epub 2015 Mar 26.
Heat shock factor 1 (HSF1) is the master transcriptional regulator of chaperone genes. HSF1 regulates the expression of the immediate-early response gene IER5, which encodes a protein that has roles in the stress response and cell proliferation. Here, we have shown that IER5 interacts with protein phosphatase 2A (PP2A) and its B55 regulatory subunits. Expression of IER5 and B55 in cells leads to HSF1 dephosphorylation and activation of HSF1 target genes. The B55 subunits directly bind to HSF1. These results suggest that IER5 functions as a positive feedback regulator of HSF1 and that this process involves PP2A/B55 and HSF1 dephosphorylation.
热休克因子1（HSF1）是伴侣蛋白基因的主要转录调节因子。HSF1调节即时早期反应基因IER5的表达，IER5编码一种在应激反应和细胞增殖中起作用的蛋白质。在此，我们已表明IER5与蛋白磷酸酶2A（PP2A）及其B55调节亚基相互作用。IER5和B55在细胞中的表达导致HSF1去磷酸化并激活HSF1靶基因。B55亚基直接与HSF1结合。这些结果表明IER5作为HSF1的正反馈调节因子发挥作用，并且该过程涉及PP2A/B55和HSF1去磷酸化。
