Identification of long non-coding RNAs in response to nanopolystyrene in Caenorhabditis elegans after long-term and low-dose exposure

The potential adverse effects of nanoplastics, such as nanopolystyrene, have received the great attention recently. However, the molecular response of organisms to nanoplastics is still largely unknown. In this study, we employed Caenorhabditis elegans as an animal model to investigate the long non-coding RNAs (lncRNAs) in response to long-term exposure to low-dose nanopolystyrene (100 nm). Based on Hiseq 2000 sequencing and qRT-PCR confirmation, we identified 36 lncRNAs (21 down-regulated lncRNAs and 15 up-regulated lncRNAs) in response to nanopolystyrene (1 μg/L). Using intestinal reactive oxygen species (ROS) production and locomotion behavior as endpoints, we found that RNAi knockdown of linc-2, linc-9, or linc-61 induced a susceptibility to nanopolystyrene toxicity, and RNAi knockdown of linc-18 or linc-50 induced a resistance to nanopolystyrene toxicity. Meanwhile, nanopolystyrene (1 μg/L) increased expressions of linc-2, linc-9, linc-18, and linc-61 and decreased linc-50 expression, suggesting that these 5 lncRNAs mediated two different responses to nanopolystyrene exposure. Bioinformatical analysis implied that these 5 lncRNAs were associated with multiple biological processes and signaling pathways. Our results demonstrated the crucial roles of lncRNAs in response to long-term exposure to low-dose nanopolystyrene in organisms.