DSS1 is a small protein, highly conserved across different species. As a member of the intrinsically disordered protein family, DSS1 interacts with different protein partners, thus forming complexes involved in diverse biological mechanisms: DNA repair, regulation of protein homeostasis, mRNA export, etc. Additionally, DSS1 has a novel intriguing role in the post-translational protein modification named DSSylation. Oxidatively damaged proteins are targeted for removal with DSS1 and then degraded by proteasome. Yet, DSS1 involvement in the maintenance of genome integrity through homologous recombination is the only function well studied in Arabidopsis research. The fact that animal DSS1 shows wide multifunctionality imposes a need to investigate the additional roles of two Arabidopsis thaliana DSS1 homologs. Having in mind the universality of various biological processes, we considered the possibility of plant DSS1 involvement in cellular homeostasis maintenance during stress exposure. Using real-time PCR and immunoblot analysis, we investigated the profiles of DSS1 gene and protein expression under oxidative stress. We grew and selected the homozygous Arabidopsis mutant line, carrying the T-DNA intron insertion in the DSS1(V) gene. The mutant line was phenotypically described during plant development, and its sensitivity to oxidative stress was characterized. This is the first report which indicates that plant DSS1 gene expression has an altered profile under the influence of oxidative stress. dss1(V)-/- plants showed an increased sensitivity to oxidative stress, germinated faster than WT, but generally showed developmental delay in further stages. Our results indicate that the DSS1 protein could be a crucial player in the molecular mechanisms underlying plant abiotic stress responses.

中文翻译：

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内在无序蛋白 AtDSS1(V) 参与植物对氧化应激的防御反应

DSS1 是一种小蛋白质，在不同物种间高度保守。作为内在无序蛋白质家族的一员，DSS1 与不同的蛋白质伙伴相互作用，从而形成涉及多种生物学机制的复合物：DNA 修复、蛋白质稳态调节、mRNA 输出等。此外，DSS1 在后处理中具有新的有趣作用- 名为 DSsylation 的翻译蛋白修饰。氧化受损的蛋白质被 DSS1 靶向去除，然后被蛋白酶体降解。然而，DSS1 通过同源重组参与维持基因组完整性是拟南芥研究中唯一得到充分研究的功能。动物 DSS1 显示出广泛的多功能性这一事实要求研究两个拟南芥 DSS1 同源物的额外作用。考虑到各种生物过程的普遍性，我们考虑了植物 DSS1 在压力暴露期间参与细胞稳态维持的可能性。使用实时 PCR 和免疫印迹分析，我们研究了氧化应激下 DSS1 基因和蛋白质的表达谱。我们培养并选择了纯合拟南芥突变系，在 DSS1(V) 基因中携带 T-DNA 内含子插入。在植物发育过程中对突变系进行了表型描述，并表征了其对氧化应激的敏感性。这是第一份表明植物 DSS1 基因表达在氧化应激影响下发生改变的报告。dss1(V)-/- 植物对氧化应激的敏感性增加，发芽速度比 WT 快，但通常在进一步阶段表现出发育延迟。