Advanced Bio-Resource R&D Center, Kyungpook National University, Daegu 41566, Korea.
Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Korea.
Molecules. 2022 May 4;27(9):2934. doi: 10.3390/molecules27092934.
The stress-responsive, SK subclass, dehydrin gene, , has been identified from the Arctic mouse-ear chickweed . CaDHN contains an unusual single cysteine residue (Cys143), which can form intermolecular disulfide bonds. Mutational analysis and a redox experiment confirmed that the dimerization of CaDHN was the result of an intermolecular disulfide bond between the cysteine residues. The biochemical and physiological functions of the mutant C143A were also investigated by in vitro and in vivo assays using yeast cells, where it enhanced the scavenging of reactive oxygen species (ROS) by neutralizing hydrogen peroxide. Our results show that the cysteine residue in CaDHN helps to enhance tolerance to abiotic stress by regulating the dimerization of the intrinsically disordered CaDHN protein, which acts as a defense mechanism against extreme polar environments.
从北极拟南芥中鉴定出应激响应的 SK 亚类脱水素基因 。CaDHN 含有一个不寻常的单个半胱氨酸残基（Cys143），可以形成分子间二硫键。突变分析和氧化还原实验证实，CaDHN 的二聚化是半胱氨酸残基之间形成分子间二硫键的结果。还通过使用酵母细胞的体外和体内测定研究了突变体 C143A 的生化和生理功能，其中它通过中和过氧化氢来增强对活性氧（ROS）的清除。我们的结果表明，CaDHN 中的半胱氨酸残基有助于通过调节内在无序的 CaDHN 蛋白的二聚化来增强对非生物胁迫的耐受性，该蛋白作为一种针对极端极地环境的防御机制。
