Transcriptome analysis of genes related to cadmium absorption and transportation in pepper

Heavy metal pollution has become a serious global problem in soil contamination. Cadmium (Cd) is a ubiquitous environmental toxic pollutant to plants, which can greatly affect their growth and development, or even lead to their death. In the present study, we performed a comparative transcriptome analysis to identify the regulators and pathways that were involved in Cd absorption and transportation in the roots, leaves and fruits of wild-type and mutant pepper plants. A total of 883,591,943 million reads were mapped to the reference genome, and 33,927 genes were identified. Sample reads and the reference genome alignment efficiency were between 78.99% to 84.57%. Finally, 798 differentially expressed genes (DEGs) were identified in the roots, leaves and fruits of the mutant and wild-type plants, including 80 up-regulated DEGs and 718 down-regulated DEGs. The DGEs were mostly related to the phenylpropanoid biosynthesis pathway and glyoxylate and dicarboxylate metabolism. In addition, some vital DEGs were identified in absorption/transportation-related pathways, such as ABC transporter and P-type ATPase. The results revealed that several genes were related to the regulation of Cd absorption and transportation. Collectively, our findings provided valuable insights into the molecular mechanism of Cd absorption and transportation in pepper.