Evolutionary Dynamics of Matrix Metalloproteases with Collagenolytic Activity in Teleosts

Matrix metalloproteases (MMPs) are zinc-dependent endopeptidases that are critical for extracellular matrix (ECM) remodeling, with key roles in tissue development and repair, and immune responses. Despite their evolutionary and functional importance, the diversification and regulatory dynamics of MMPs genes in teleosts remain poorly understood. This study investigates the evolutionary history of MMPs with collagenolytic activity in the vertebrates with an emphasis on teleosts. Using comparative genomics and phylogenetics we identified conserved single-copy mmp2 and mmp9 genes and duplicated mmp11 and mmp13 paralogs in all non-salmonid teleosts. Phylogenetic and synteny analyses suggest that mmp11 paralogs originated from the teleost-specific genome duplication (TSGD), whereas the origin of mmp13 paralogs originated from a more complex evolutionary scenario. Protein domain analysis confirmed conserved catalytic motifs across species, supporting functional retention. The expression patterns of paralog genes were studied in two model marine teleosts, the Sparus aurata (gilthead sea bream) and Dicentrarchus labrax (European sea bass). Developmental and adult tissue transcriptome analyses revealed three major expression patterns among the paralogs: similar expression, stage-specific or tissue-specific expression. The overall data point to varied evolutionary dynamics of MMP genes in the teleosts, tracing their origin to different whole-genome duplication events. Expression profiles on paralog genes in model teleosts suggest regulatory sub-functionalization as the most possible fate of retained MMPs paralogs in teleosts following whole-genome duplication.