Comparative Transcriptomic and Proteomic Analyses Identify Byssogenesis-Associated Genes in the Mediterranean Mussel Mytilus galloprovincialis Lamarck, 1819

Mussels' byssus and their adhesion ability play a crucial role in their attachment and artificial cultivation of mussels. In this study, transcriptomic and proteomic analyses were performed to identify byssogenesis-associated genes in the Mediterranean mussel <i>Mytilus galloprovincialis</i> Lamarck, 1819, seeking to advance our knowledge of the molecular basis of byssal secretion in mussels. Transcriptomic analysis identified 1742 and 1498 differentially expressed genes in the foot tissue of <i>M. galloprovincialis</i> at 9 h and 24 h post-byssal ablation, respectively. Meanwhile, proteomic analysis revealed 1254 and 484 differentially expressed proteins at the same two time points. Integrated analysis identified 121 genes differentially expressed at both transcript and protein levels. Among these genes, 44 were significantly upregulated, and they may constitute high-confidence gene sets associated with mussel byssogenesis. Notably, they included genes encoding tyrosinase-like protein, low affinity immunoglobulin epsilon Fc receptor, and O-methyltransferase MdmC. They were enriched in KEGG pathways, including metabolism of amino acids, lipid metabolism, nucleotide metabolism, and immune system. Quantitative real-time PCR was performed on seven selected genes, confirming that their expression patterns were consistent with those observed in transcriptomic and proteomic sequencing. This study provides novel data and insights for understanding the molecular basis involved in byssus development of <i>M. galloprovincialis</i>.