Differential feedback regulation of ethylene biosynthesis in pulp and peel tissues of banana fruit

Abstract

The feedback regulation of ethylene biosynthesis in banana [Musa sp. (AAA group, Cavendish subgroup) cv. Grand Nain] fruit was investigated in an attempt to clarify the opposite effect of 1-methylcyclopropene (1-MCP), an ethylene action inhibitor, before and after the onset of ripening. 1-MCP pre-treatment completely prevented the ripening-induced effect of propylene in pre-climacteric banana fruit, whereas treatment after the onset of ripening stimulated ethylene production. In pre-climacteric fruit, higher concentrations of propylene suppressed ethylene production more strongly, despite their earlier ethylene-inducing effect. Exposure of the fruit ripened by propylene to 1-MCP increased ethylene production concomitantly with an increase in 1-aminocyclopropane-1-carboxylate (ACC) synthase activity and ACC content, and prevented a transient decrease in MA-ACS1 transcripts in the pulp tissues. In contrast, in the peel of ripening fruit, 1-MCP prevented the increase in ethylene production and subsequently the ripening process by reduction of the increase in MA-ACS1 and MA-ACO1 transcripts and of ACC synthase and ACC oxidase activities. These results suggest that ethylene biosynthesis in ripening banana fruit may be controlled negatively in the pulp tissue and positively in the peel tissue. This differential regulation by ethylene in pulp and peel tissues was also observed for MA-PL, MA-Exp, and MA-MADS genes.

Effects of AminoethoxyVinylGlycine (AVG) Spraying Time at Preharvest Stage to Ethylene Biosynthesis of Cavendish Banana (Musa AAA)

“…Ten days after harvest, ethylene production of all fruits (with or without AVG spraying) was not significant different. This result is quite appropriate with results previously reported by Innaba [Innaba et al, 2007] respectively.…”

Regulation of ethylene biosynthesis at the level of 1-aminocyclopropane-1-carboxylate oxidase (ACO) gene

“…However, Trivellini et al (2011) have shown that ethylene biosynthesis can be under both positive and negative feedback regulatory mechanisms in a tissue-temporal-specific manner during flower development and senescence depending on differential expression of ACS and ACO genes. Similarly, the studies in tomato and banana have shown a differential feedback regulation of ethylene biosynthesis enzymes between pre-climacteric and ripening fruits and also between different tissues (Nakatsuka et al 1998;Inaba et al 2007). …”

“…A positive feedback regulation, through an increase in ethylene production triggered by exogenous ethylene, with the activation of ACS and/or ACO has been reported for petunia (Tang and Woodson 1996), carnation (Jones and Woodson 1997), and orchid (O'Neill et al 1993). A negative feedback regulation has been shown for transgenic petunia flowers (Wilkinson et al 1997) and ripening tomato and banana (Nakatsuka et al 1998;Inaba et al 2007). However, Trivellini et al (2011) have shown that ethylene biosynthesis can be under both positive and negative feedback regulatory mechanisms in a tissue-temporal-specific manner during flower development and senescence depending on differential expression of ACS and ACO genes.…”

Effect of physiological harvest stages on the composition of bioactive compounds in Cavendish bananas

“…Indeed, the change in phenolic content in immature green fruit unable to respond to ethylene might be under the control of developmental cues while in mature green fruit both ethylene and developmental cues might be involved. Recent progress on the ripening process in banana strongly suggests that the ripening process of banana peel tissue clearly differs from that of the pulp (Domínguez and Vendrell, 1994;Clendennen and May, 1997;Inaba et al, 2007), thus suggesting tissuespecific regulation of the ripening process in this species. Independent of climactic season and fruit physiological stage at harvest, phenol content accumulates differentially in peel tissue compared to pulp tissue during ripening.…”