Abstract:
Arsenic (As), a metalloid of considerable toxicity, has become increasingly bioavailable through anthropogenic activities, raising As contamination levels in groundwater and agricultural soils worldwide. This bioavailability has profound implications for plant biology and farming systems. As can detrimentally affect crop yield and pose risks of bioaccumulation and subsequent entry into the food chain. Upon exposure to As, plants initiate a multifaceted molecular response involving crucial signaling pathways, such as those mediated by calcium, mitogen-activated protein kinases, and various phytohormones (e.g., auxin, methyl jasmonate, cytokinin). These pathways, in turn, activate enzymes within the antioxidant system, which combat the reactive oxygen/nitrogen species (ROS and RNS) generated by As-induced stress. Plants exhibit a sophisticated genomic response to As, involving the upregulation of genes associated with uptake, chelation, and sequestration. Specific gene families, such as those coding for aquaglyceroporins and ABC transporters, are key in mediating As uptake and translocation within plant tissues. Moreover, we explore the gene regulatory networks that orchestrate the synthesis of phytochelatins and metallothioneins, which are crucial for As chelation and detoxification. Transcription factors, particularly those belonging to the MYB, NAC, and WRKY families, emerge as central regulators in activating As-responsive genes. On a post-translational level, we examine how ubiquitination pathways modulate the stability and function of proteins involved in As metabolism. By integrating omics findings, this review provides a comprehensive overview of the complex genomic landscape that defines plant responses to As. Knowledge gained from these genomic and epigenetic insights is pivotal for developing biotechnological strategies to enhance crop As tolerance.
摘要:
砷(As),具有相当毒性的类金属,通过人为活动变得越来越生物可利用,提高全球地下水和农业土壤的污染水平。这种生物利用度对植物生物学和农业系统具有深远的影响。这可能会对作物产量产生不利影响,并带来生物累积和随后进入食物链的风险。暴露于As后,植物启动涉及关键信号通路的多方面分子反应,比如那些由钙介导的,丝裂原活化蛋白激酶,和各种植物激素(例如,生长素,茉莉酸甲酯,细胞分裂素)。这些途径,反过来,激活抗氧化系统内的酶,它们对抗由As诱导的应激产生的活性氧/氮物质(ROS和RNS)。植物对As表现出复杂的基因组反应,涉及与摄取相关的基因的上调,螯合,和隔离。特定的基因家族,例如编码aquaglyceroporoins和ABC转运蛋白的编码,是介导植物组织内As摄取和转运的关键。此外,我们探索协调植物螯合素和金属硫蛋白合成的基因调控网络,这对As螯合和解毒至关重要。转录因子,特别是那些属于MYB的,NAC,和WRKY家族,作为激活As反应基因的中央调节因子出现。在翻译后的水平,我们研究了泛素化途径如何调节参与As代谢的蛋白质的稳定性和功能。通过整合组学研究结果,这篇综述提供了定义植物对As反应的复杂基因组景观的全面概述。从这些基因组和表观遗传见解中获得的知识对于开发生物技术策略以增强作物As耐受性至关重要。