Polymorphisms of ppp2cab gene and their association with growth traits in European seabass (Dicentrarchus labrax Linnaeus, 1758) and their in silico structural evaluation

Abstract

The ppp2cab gene encodes the catalytic alpha subunit of protein phosphatase 2A (PP2A), a key regulator of cellular growth and proliferation. However, genetic variation within ppp2cab has not been previously investigated in European seabass (Dicentrarchus labrax). The aim of this study was to identify single nucleotide polymorphisms (SNPs) in a partial region of the ppp2cab gene, evaluate the associations between these polymorphisms and growth-related traits, and investigate the structural effects of coding region variants using in silico analyses. A total of seven SNPs, including three exonic and four intronic variants, were identified in the targeted ppp2cab gene region. Two exonic SNPs resulted in nonsynonymous amino acid substitutions (Ala102Pro and Asp151Asn), whereas the third exonic SNP (g.7857G>A) was synonymous. Only the synonymous SNP g.7857G>A showed significant associations with multiple growth-related traits, including body weight, fillet weight, standard length, and several morphometric measurements (p < 0.05). Structural analyses indicated that Ala102Pro and Asp151Asn are located outside the predicted catalytic center of Ppp2cab and are unlikely to substantially alter the overall protein architecture, although localized effects cannot be excluded. The polymorphisms identified in the ppp2cab gene provide a basis for future validation studies in different populations and functional studies.