Uptake, Agglomeration, and Detoxification of Trace Metals and Metalloids in Plants

Trace metals and metalloids (TMMs) can have positive and negative effects on plant growth, and their toxicity levels can vary greatly among living organisms due to differences in metabolic activity. Therefore, a comprehensive elucidation of plant biochemical processes, transportation mechanisms, and detoxification processes is required crucial. While prior research has provided some insights into these subjects, however there remains a gap in understanding that necessitates further exploration. Thus, this manuscript aims to address this gap by providing a detailed examination of the transportation processes of TMMs in plants, along with an exploration of the various signaling mechanisms that govern TMMs accumulation and sequestration within plant cells. For this study, a rigorous methodology was employed, including a comprehensive web search and bibliometric analysis to identify pertinent articles, discern publication trends, and analyze keyword co-occurrences. Moreover, this manuscript highlights several key mechanisms, such as the regulatory roles of auxin, glutathione, nitric oxide, and associated transporters in modulating TMMs dynamics within soil and plant systems. The uptake and agglomeration of TMMs in root exodermis cells, as well as their subsequent transit through symplastic and apoplastic channels into the xylem, are significantly influenced by morphophysiological routes. Additionally, the pivotal role of glutathione in the synthesis of phytochelatins, thiol (-SH), and metallothionein is underscored, along with its function in inhibiting the mobility of TMM ions by facilitating their sequestration within cell walls and vacuoles. Furthermore, the manuscript explains how the interplay between auxin and nitric oxide is augmented through the s-nitrosylation of auxin signaling, thereby promoting plant growth and enhancing resilience to stress induced by metalloids. This article offers a comprehensive understanding of the diverse routes and intricate processes involved in the absorption and detoxification of TMMs in plants.