Eukaryotic reference-based transcriptome sequencing and analysis of 18 Mytilus edulis samples

This study focuses on reference-based transcriptome sequencing and analysis of 18 Mytilus edulis (blue mussel) spat samples, aiming to explore the inhibitory mechanism of 5 newly developed non-oxidizing circulating water treatment agents on the attachment of this typical marine fouling organism.Laboratory experiments included 96 h semi-static acute toxicity tests and 24 h semi-static chronic inhibition tests, with field verification conducted in the intertidal zone of Ganyu, Jiangsu Province. Key results showed all agents exhibited significant dose-effect relationships with M. edulis spat: Agent 5 achieved 100% attachment inhibition at the lowest concentration of 10 mg/L, demonstrating the strongest inhibitory activity; Agent 3 stably inhibited attachment at 15 mg/L and showed comprehensive effectiveness against multiple fouling organisms (including oysters and sea anemones), making it the optimal candidate for engineering applications.Transcriptome analysis identified 2746 differentially expressed genes (2039 upregulated, 707 downregulated) between the treatment and control groups. These genes were significantly enriched in pathways related to byssus secretion (e.g., Mfp3, Mfp5, Mfp7) and cell adhesion (Focal adhesion, Adherens junction). Phenotypic observations confirmed that the agents significantly reduced byssus number, total length, diameter, and increased shedding frequency in treated spat, indicating interference with byssus synthesis and adhesion stability. Field tests (September 19 to October 31, 2025) further verified the practical anti-fouling effect of the agents, with consistent results with laboratory experiments.This research provides a scientific basis for the optimal dosage of fouling control agents in nuclear power plant cooling systems and other marine engineering, and enriches the understanding of the molecular mechanisms underlying fouling organism attachment inhibition.