Main Molecular Pathways Associated with Copper Tolerance Response in Imperata cylindrica by de novo Transcriptome Assembly

Abstract

The metallophyte Imperata cylindrica inhabits copper (Cu) polluted soils in large areas from Central Chile. Here, we subjected clonal vegetative plantlets to 300 mg Cu kg−1 of substrate for 21 days to identify the main molecular pathways involved in the response to Cu stress. Transcriptomic analyses were performed for shoots and roots, with and without Cu supply. RNA-Seq and de novo transcriptome assembly were performed to identify the gene response associated with molecular mechanisms of Cu tolerance in I. cylindrica. De novo transcriptome revealed a total of 200,521 transcripts (1777 bp) comprising ~91% complete ultra-conserved genes in the eukaryote and Plantae database. The differentially expressed genes (DEGs) in roots were 7386, with 3558 of them being up-regulated and the other 3828 down-regulated. The transcriptome response in shoots was significantly less, showing only 13 up-regulated and 23 down-regulated genes. Interestingly, DEGs mainly related with actin and cytoskeleton formation, and to a minor degree, some DEGs associated with metal transporters and superoxide dismutase activity in root tissues were found. These transcriptomic results suggest that cytoskeleton could be acting as a mechanism of Cu-binding in the root, resulting in a high Cu tolerance response in this metallophyte, which deserve to be analyzed ultra-structurally. Our study contributes to reinforcing the potential of I. cylindrica as a candidate plant species to be used as a phytoremediation agent in Cu-contaminated environments.

Tissue Distribution and Biochemical Changes in Response to Copper Accumulation in Erica australis L.

“…High Cu concentration damage epidermal cells, reducing mitochondria and inducing cortical cell death [ 17 ]. There are gene families that play a key role in controlling Cu stress [ 19 ], and some of them are related to actin and cytoskeleton formation, metal transporters and superoxide dismutase activity in root tissues [ 20 ]. The root tissues of rice seedlings accumulate over 40% of the Cu present in the medium, and 60% of it was not fully available for transport [ 21 ].…”

Transcriptomics, proteomics, and metabolomics interventions prompt crop improvement against metal(loid) toxicity

“…Most proteins functionally interact with other small and large molecules (including other proteins and metabolites) to maintain cellular homeostasis. Protein–metabolite interactions are vital in cell signaling pathways (Venegas-Molina et al 2023 ). Large-scale proteomics analyses can unravel the networking between proteins and metabolic pathways (Yusuf et al 2022 ), but studies are limited.…”

“…Recent developments include chemoproteomic workflows and an interactomics method using nuclear magnetic resonance (NMR) to systematically identify targeted metabolite–protein interactions (Li et al 2022c ). Techniques like limited proteolysis-coupled mass spectrometry (LiP-MS) have also been introduced to identify novel protein–metabolite interactions related to plant regulatory mechanisms (Venegas-Molina et al 2023 ).…”

Efflux Pump Inhibitors in Controlling Antibiotic Resistance: Outlook under a Heavy Metal Contamination Context

“…The main groups of secondary plant metabolites, many of which function as EPIs, include phenolics, alkaloids, saponins, terpenes, lipids, and carbohydrates that have been identified using analytical equipment, such as HPLC and MS/MS ( Table 2 ) [ 54 , 55 ]. Exposure to Cu significantly increased the synthesis of phenolic compounds in the shoots of Imperata cylindrica , which is a grass in Chile that grows in soil with varying distributions of Cu contamination [ 56 ]. Under stress conditions, phenols act as chelating metals through hydroxyl and carboxyl groups and inhibit lipid peroxidation by trapping alkoxyl radicals.…”

“…Under stress conditions, phenols act as chelating metals through hydroxyl and carboxyl groups and inhibit lipid peroxidation by trapping alkoxyl radicals. Therefore, exposure to toxic elements leads to the formation of reactive oxygen species (ROS), which consequently increases the production of phenolic compounds in plants [ 56 ]. Phenolics from root exudation depend on metal concentrations or plant species [ 57 ].…”