Genome-wide identification and expression analysis of beta-galactosidase family members during fruit softening of peach [Prunus persica (L.) Batsch]

Plant β-galactosidase (β-Gal) is an important glycosyl hydrolase, which is associated with cell wall biogenesis and modification during fruit softening. However, the roles of β-Gal family members in peach fruit softening remain unclear. In the present study, we identified 17 PpBGAL genes in peach genome, and these were investigated using bioinformatics including chromosomal locations, phylogenetic relationships, gene structure and domain and promoter analyses. Furthermore, quantitative real-time PCR analysis during fruit storage of four peach varieties with different softening characteristics suggested that PpBGAL genes, especially PpBGAL2 and PpBGAL16, may be required for peach fruit softening. These results will be useful for further functional analyses of the β-Gal gene family in plants.