Transcriptomic changes in the ovaries of scallop Chlamys farreri exposed to benzo[a]pyrene

Abstract

In this study, digital gene expression (DGE) sequencing technology was used to identify alterations in gene transcription of the ovarian tissue of Chlamys farreri (C. farreri) exposed to benzo[a]pyrene (BaP) pollutants. A total of 124 genes were detected differentially expressed with 42 up-regulated and 82 down-regulated genes in BaP DGE libraries. Gene ontology annotation and kyoto encyclopedia of genes and genomes pathway analyses were performed on all genes to elucidate their biological functions and processes. The results showed that numerous enriched differentially expressed genes related to “detoxification process”, “damage effects to extracellular matrix and cell interactions”, “endocrine disrupting effects” and “tissue damage responses”. Quantitative RT-PCR procedure was executed to understand the expression patterns of several important reproductive-related genes. To supplement the reproductive toxicity of BaP, histological analysis of the ovaries illustrated that after 21 days higher dose of BaP exposure, the immature oocytes and degenerated oocytes increased. The study aims to provide reference data for future study of organic pollutions in aquatic mollusks.