Giesguth Miriam, Sahm Arne, Simon Swen, Dietz Karl-Josef
Biochemistry and Physiology of Plants, Bielefeld University, 33615 Bielefeld, Germany.
Biochemistry and Physiology of Plants, Bielefeld University, 33615 Bielefeld, Germany.
FEBS Lett. 2015 Mar 12;589(6):718-25. doi: 10.1016/j.febslet.2015.01.039. Epub 2015 Feb 7.
The hypothesis is tested that some heat stress transcription factors (HSFs) are activated after formation of inter- or intramolecular disulfide bonds. Based on in silico analyses we identified conserved cysteinyl residues in AtHSFA8 that might function as redox sensors in plants. AtHSFA8 represents a redox-sensitive transcription factor since upon treatment of protoplasts with H2O2 YFP-labeled HSFA8 was translocated to the nucleus in a time-dependent manner. Site-directed mutagenesis of the conserved residues Cys24 and Cys269 blocked translocation of HSFA8 to the nucleus. The findings concur with a model where HSFA8 functions as redox sensing transcription factor within the stress-responsive transcriptional network.
该假说认为，一些热应激转录因子（HSF）在分子间或分子内二硫键形成后被激活。基于计算机分析，我们在拟南芥热应激转录因子A8（AtHSFA8）中鉴定出保守的半胱氨酸残基，这些残基可能在植物中作为氧化还原传感器发挥作用。AtHSFA8代表一种氧化还原敏感的转录因子，因为在用过氧化氢处理原生质体后，黄色荧光蛋白标记的HSFA8会以时间依赖性方式转移到细胞核中。对保守残基Cys24和Cys269进行定点诱变可阻止HSFA8向细胞核的转移。这些发现与一个模型相符，即HSFA8在应激反应转录网络中作为氧化还原感应转录因子发挥作用。
