Comparative transcriptome analysis reveals candidate genes related to cadmium accumulation and tolerance in two almond mushroom (Agaricus brasiliensis) strains with contrasting cadmium tolerance

• Published in: PloS one 2020-09, Vol.15 (9), p.e0239617
• Main Authors: Liu, Peng-Hu, Huang, Zai-Xing, Luo, Xu-Hui, Chen, Hua, Weng, Bo-Qi, Wang, Yi-Xiang, Chen, Li-Song
• Format: Article
• Language: English
• Subjects: Accumulation; Agaricus; Agaricus - drug effects; Agaricus - genetics; Agaricus - metabolism; Agaricus brasiliensis; Agriculture; ATP-Binding Cassette Transporters - genetics; ATP-Binding Cassette Transporters - metabolism; Bioaccumulation; Biology and Life Sciences; Cadmium; Cadmium - metabolism; Cadmium - toxicity; Cell cycle; Cell walls; Cultivars; Deoxyribonucleic acid; DNA; DNA biosynthesis; DNA repair; DNA Repair - drug effects; DNA Replication - drug effects; Drug Tolerance; Ecology; Efflux; Engineering research; Fungal Proteins - genetics; Fungal Proteins - metabolism; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Fungal; Genes; Genetic aspects; Glutathione; Glutathione transferase; Glutathione Transferase - genetics; Glutathione Transferase - metabolism; Laboratories; Molecular biology; Molecular modelling; Mushrooms; Mycelia; Mycelium - chemistry; Mycelium - drug effects; Mycelium - growth & development; Organic acids; Physical Sciences; Physiological aspects; Physiology; Plant hardiness; Pollution tolerance; Polysaccharides; Polysaccharides - metabolism; Proteins; Repair; Replication; Ribonucleic acid; RNA; RNA sequencing; RNA, Fungal - chemistry; RNA, Fungal - metabolism; RNA-Seq; Saccharides; Software; Stability; Sulfur; Transcriptome; Trehalose; Zinc
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0239617

Cadmium (Cd) is a toxic metal occurring in the environment naturally. Almond mushroom (Agaricus brasiliensis) is a well-known cultivated edible and medicinal mushroom. In the past few decades, Cd accumulation in A.brasiliensis has received increasing attention. However, the molecular mechanisms of Cd-accumulation in A. brasiliensis are still unclear. In this paper, a comparative transcriptome of two A.brasiliensis strains with contrasting Cd accumulation and tolerance was performed to identify Cd-responsive genes possibly responsible for low Cd-accumulation and high Cd-tolerance. Using low Cd-accumulating and Cd-tolerant (J77) and high Cd-accumulating and Cd-sensitive (J1) A.brasiliensis strains, we investigated 0, 2 and 5 mg L-1 Cd-effects on mycelium growth, Cd-accumulation and transcriptome revealed by RNA-Seq. A total of 57,884 unigenes were obtained. Far less Cd-responsive genes were identified in J77 mycelia than those in J1 mycelia (e.g., ABC transporters, ZIP Zn transporter, Glutathione S-transferase and Cation efflux (CE) family). The higher Cd-accumulation in J1 mycelia might be due to Cd-induced upregulation of ZIP Zn transporter. Cd impaired cell wall, cell cycle, DNA replication and repair, thus decreasing J1 mycelium growth. Cd-stimulated production of sulfur-containing compounds, polysaccharides, organic acids, trehalose, ATP and NADPH, and sequestration of Cd might be adaptive responses of J1 mycelia to the increased Cd-accumulation. DNA replication and repair had better stability under 2 mg L-1 Cd, but greater positive modifications under 5 mg L-1 Cd. Better stability of DNA replication and repair, better cell wall and cell cycle stability might account for the higher Cd-tolerance of J77 mycelia. Our findings provide a comprehensive set of DEGs influenced by Cd stress; and shed light on molecular mechanism of A.brasiliensis Cd accumulation and Cd tolerance.