Transcriptome analysis of sea cucumber (Apostichopus japonicus) in southern China under heat stress

Sea cucumber (Apostichopus japonicus) is a significant aquatic economic species globally. However, the advancement of the sea cucumber aquaculture industry is impeded by its high susceptibility to elevated temperatures. To elucidate the impact of high temperature on physiological changes, gene expression, and metabolic responses in sea cucumbers, we conducted transcriptional profiling of A. japonicus under heat stress. Our results revealed 3691 differentially expressed genes (DEGs), comprising 1629 up-regulated and 2062 down-regulated genes, between the control and treatment groups. Analysis of the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Protein-Protein Interaction Networks (PPI) indicated that high-temperature stress triggered the expression of stress defense-related genes while inhibiting the expression of genes associated with development and metabolism. Furthermore, 30 out of 39 DEGs were annotated to heat shock protein genes, underscoring the crucial role of these genes in the regulatory mechanism of A. japonicus in response to heat stress. In summary, our findings provide fundamental insights for further investigation into the molecular mechanisms in A. japonicus under high-temperature stress and may contribute to the development of novel strategies for identifying heat-tolerant candidate genes through the analysis of their transcriptional changes in the future.