Identification of EIL and ERF Genes Related to Fruit Ripening in Peach.

Peach () is a climacteric fruit with a relatively short shelf life due to its fast ripening or softening process. Here, we report the association of gene families encoding ethylene insensitive-3 like (EIL) and ethylene response factor (ERF) with fruit ripening in peach. In total, 3 and 12 PpERFs were highly expressed in fruit, with the majority showing a peak of expression at different stages. All three EILs could activate ethylene biosynthesis genes and . One out of the 12 , termed , is a homolog of ripening-associated in tomato, with a consistently high expression throughout fruit development and an ability to activate and . Additionally, four subgroup F PpERFs harboring the EAR repressive motif were able to repress the promoter but could also activate the promoter. Promoter deletion assay revealed that PpEILs and PpERFs could participate in transcriptional regulation of through either direct or indirect interaction with various cis-elements. Taken together, these results suggested that all three and are candidates involved in ethylene biosynthesis, and EAR motif-containing may function as activator or repressor of ethylene biosynthesis genes in peach. Our study provides an insight into the roles of EILs and ERFs in the fruit ripening process.