Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China.
Jiangsu Academy of Forestry, Nanjing 211153, China.
Cells. 2019 Dec 27;9(1):76. doi: 10.3390/cells9010076.
Interferon gamma-induced lysosomal thiol reductase (GILT) is abundantly expressed in antigen-presenting cells and participates in the treatment and presentation of antigens by major histocompatibility complex II. Also, GILT catalyzes the reduction of disulfide bonds, which plays an important role in cellular immunity. (1) Background: At present, the studies of GILT have mainly focused on animals. In plants, GILT homologous gene (: ) was discovered in the forward screen of mutants with compromised responses to sulphur nutrition. However, the complete properties and functions of poplar OSH1 are unclear. In addition, CdCl stress is swiftly engulfing the limited land resources on which humans depend, restricting agricultural production. (2) Methods: A prokaryotic expression system was used to produce recombinant PtOSH1 protein, and Western blotting was performed to identify its activity. In addition, a simplified version of the floral-dip method was used to transform . (3) Results: Here, we describe the identification and characterization of OSH1 from . The deduced PtOSH1 sequence contained CQHGX2ECX2NX4C and CXXC motifs. The transcript level of was increased by cadmium (Cd) treatment. In addition, recombinant PtOSH1 reduced disulfide bonds. A stress assay showed that -overexpressing (OE) lines had greater resistance to Cd than wild-type (WT) plants. Also, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in -OE plants were significantly higher than those in WT . These results indicate that PtOSH1 likely plays an important role in the response to Cd by regulating the reactive oxygen species (ROS)-scavenging system. (4) Conclusions: PtOSH1 catalyzes the reduction of disulfide bonds and behaves as a sulfhydryl reductase under acidic conditions. The overexpression of in promoted root development, fresh weight, and dry weight; upregulated the expression levels of ROS scavenging-related genes; and improved the activity of antioxidant enzymes, enhancing plant tolerance to cadmium (Cd) stress. This study aimed to provide guidance that will facilitate future studies of the function of PtOSH1 in the response of plants to Cd stress.
干扰素γ诱导的溶酶体硫醇还原酶（GILT）在抗原呈递细胞中大量表达，并参与主要组织相容性复合物 II 对抗原的处理和呈递。此外，GILT 催化二硫键的还原，这在细胞免疫中起着重要作用。
（1）背景：目前，GILT 的研究主要集中在动物上。在植物中，通过对硫营养反应受损突变体的正向筛选，发现了 GILT 同源基因（：）。然而，杨树 OSH1 的完整性质和功能尚不清楚。此外，CdCl 胁迫迅速吞噬了人类赖以生存的有限土地资源，限制了农业生产。
（2）方法：利用原核表达系统生产重组 PtOSH1 蛋白，并通过 Western blot 鉴定其活性。此外，还使用简化的花浸法转化。
（3）结果：在这里，我们描述了从杨树中鉴定和表征 OSH1。推测的 PtOSH1 序列包含 CQHGX2ECX2NX4C 和 CXXC 基序。镉（Cd）处理后，转录水平增加。此外，重组 PtOSH1 还原二硫键。应激试验表明，过表达（OE）系比野生型（WT）植物对 Cd 的抗性更强。此外，-OE 植物中超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）的活性明显高于 WT。这些结果表明，PtOSH1 可能通过调节活性氧（ROS）清除系统在对 Cd 的反应中发挥重要作用。
（4）结论：PtOSH1 在酸性条件下催化二硫键还原，并作为巯基还原酶发挥作用。在中过表达 促进了根系发育、鲜重和干重；上调了 ROS 清除相关基因的表达水平；并提高了抗氧化酶的活性，增强了植物对 Cd 胁迫的耐受性。本研究旨在为杨树 PtOSH1 对 Cd 胁迫响应功能的进一步研究提供指导。
