Integrative analysis of FOX genes in fish: Evolution, structure, and functional roles in environmental stress...

The forkhead box (FOX) gene family encodes transcription factors that control growth, development, stress response, and metabolism across vertebrates. While FOX genes have been widely explored in a few model fish species, their roles in Mugil cephalus, a commercially and ecologically important euryhaline species, are still not well described. Current study, explored the first ever genomic and structural analysis of FOX genes in M. cephalus. In this study, 42 FOX genes were identified in the genome of M. cephalus and the presence of conserved forkhead domains was confirmed. The study showed that there are significant differences in the physicochemical traits of studied proteins and the phylogenetic analysis grouped these proteins into 18 clades. Duplication history pointed toward a number of genome-wide duplication events, with all of them shaped mainly by purifying selection. The synteny analysis suggested that chromosomal arrangements were mostly conserved with humans, indicating a deep evolutionary link. The organization of Motif and domains pointed toward functional diversification, while structure modeling (2D and 3D) revealed noticeable variation in folding patterns of amino acids. Moreover, mutation predictions reported various destabilizing substitutions that could weaken the stability of proteins. In conclusion, this study gives the first integrated overview of FOX genes in M. cephalus, opening new perspectives on their evolution and possible functions in vertebrate species. Experimental studies are aimed in future to confirm the role of FOX genes for improved aquaculture practices, stress tolerance, and bio-conservation of M. cephalus.