Genome-wide identification and expression analysis of beta-galactosidase family members in sweetpotato [ Ipomoea batatas (L.) Lam.]

Background: Sweetpotato (Ipomoea batatas (L.) Lam.) serves as an important food source for human beings. β-galactosidase (β-gal) is a glycosyl hydrolase involved in cell wall modification, which plays essential roles in plant development and environmental stress adaptation. However, the function of β-gals genes in sweetpotato has yet to be reported.Results: In this study, 17 β-galactosidase genes (Ibbgal) were identified in sweetpotato, which were classified into seven subfamilies using interspecific phylogenetic and comparative analyses. The promoter regions of Ibbgals harbored several stress, hormone and light responsive cis-acting elements. The Ibbgal genes were specifically expressed in different tissues and varieties, and differentially expressed under various hormonal treatments, and abiotic and biotic stresses.Conclusions: These findings suggest that Ibbgals may involve in plant development and stress responses through regulating the metabolism of cell wall polysaccharides.