Transcriptomic analysis of intestinal tissue of earthworm exposed to Tri-n-butyl phosphate (TnBP)

Purpose: The objective of this study was to investigate the TnBP-induced intestinal toxicity mechanism on earthworm Eisenia fetida. Methods: The intestinal tissues of nine earthworms under control and 10 mg/kg TnBP treatments were separately pooled into three replicates (three earthworms per replication) to obtain sufficient amounts of RNA for transcriptomic assessments, using BGISEQ-500. qRT–PCR validation was performed using SYBR Green assays. Results: A total of 10,401 contig sequences, mapped to 313 KEGG pathways,were classified. Scatter plots of DEGs based on the results showed that 3786 genes were significantly up regulated and 1084 genes were significantly downregulated at a P-value cut off of 0.01 . Pathway enrichment analysis of DEGs was performed to identify the potential biological functions for the interaction of genes based on the KEGG database. Pathways of the Digestive system were severely affected in the transcriptome dataset for the pathways of Protein digestion and absorption, Salivary secretion, Gastric acid secretion, and Bile secretion disruption. This is in accordance with the intestinal injury results of the digestive tract degradation and the alteration of digestive activities. Overall design: RNA-seq of earthworm intestinal tissue in control group and in treatment group, both containing three replicates.