Transcriptome analysis reveals the mechanism of common carp brain injury after exposure to lead.

Lead, a widespread industrial pollutant, has been known as a powerful neurotoxin that could affect the central nervous system. Accumulating evidences demonstrated that lead exposure could result in the damage of brain tissues both in fish and human. However, the mechanism of lead induced brain injury has not been fully elucidated. The purpose of this study was to clarify the possible mechanism of common carp brain injury after exposure to lead through transcriptome analysis. Transcriptome analysis showed that 2141 differentially expressed genes were identified. Among these, 502 genes were up-regulated and 1639 genes were down-regulated. Meanwhile, GO enrichment analysis showed Transport, biological_process, DNA-templated (regulation of transcription) and signal transduction contained the most differential genes in the biological process. Furthermore, KEGG pathway enrichment analysis showed Ion channels, GnRH signaling pathway, cell adhesion molecules, Wnt signaling pathway, and calcium signaling pathway were significantly enriched. In addition, 10 differentially expressed genes were selected for qRT-PCR detection, and the results demonstrated that the selected genes exhibited the same trends with the RNA-Seq results, which indicates the transcriptome sequencing data is reliable. In conclusion, the above results provide a theoretical basis for clarifying the relationship between lead exposure and brain injury in common carp and for further studying of the genes related to lead poisoning.