The Fibrillar Collagens of Bony Fish: Genes, Proteins, and Biomedical Applications.

Fibrillar collagens are the most abundant structural proteins in vertebrates, forming the backbone of connective tissues such as skin, bone, tendon, and cartilage. In bony fish (teleosts), fibrillar collagens exhibit unique genetic and biochemical properties that reflect a complex evolutionary history of this taxonomic group and its adaptation to diverse aquatic environments-from tropical to polar habitats. This review summarises the current understanding of the genetic organisation and biochemical characteristics of fibrillar collagens in bony fish. They show significant differences in amino acid composition to mammalian collagens, especially in cold-adapted species, where collagens display lower thermal stability and reduced hydroxyproline content relative to their mammalian counterparts.Advances in genomic, transcriptomic, and proteomic profiling have provided new perspectives on the molecular diversity and tissue-specific roles of collagen chains in teleosts. Furthermore, the biomedical potential of fish-derived collagens is receiving growing attention, particularly in biomaterials, wound healing, tissue engineering, and drug delivery systems, owing to their biocompatibility, low immunogenicity, and ease of extraction from byproducts of the fishing industry.By looking at molecular, structural, and applied perspectives, this review highlights the relevance of bony fish collagens as a subject of fundamental biological interest and as a valuable resource for biotechnological and biomedical innovation.