Phylogenetic relationships and expression in response to low temperature of a catalase gene in banana (Musa acuminata cv. Grand Nain) fruit

For many plants, particularly those of tropical and subtropical origin, chilling injury occurs as a result of their exposure to low, but nonfreezing temperatures. Banana fruits are highly susceptible to chilling injury, but little is known about the role of genes that scavenge reactive oxygen species in fruits during chilling injury. In this study, a catalase gene, designated MaCat2, was isolated from Musa acuminata cv. Grand Nain fruits. The full-length cDNA sequence is 1,479 bp, and based on phylogenetic analysis, it is related to catalase type 2 genes from Elaeis guineensis and Zantedeschia aethiopica. Expression studies revealed that the MaCat2 gene was induced in severe stress of banana fruits. MaCat2 expression in banana peel increased in response to both low temperature and physical damage, but not so under heat stress or during normal fruit ripening. These findings suggest that MaCat2 is induced in banana peel by cold treatment and is regulated at transcriptional level, possibly playing a role in chilling injury response of banana fruit.