Rose (Rosa hybrida) Ethylene Responsive Factor 3 Promotes Rose Flower Senescence via Direct Activation of the Abscisic Acid Synthesis-Related 9-CIS-EPDXYCAROTENOID DIOXYGENASE Gene

During plant senescence, energy and nutrients are transferred to young leaves, fruits or seeds. However, senescence reduces flower quality, which leads to huge economic losses in flower production. Ethylene is an important factor affecting the quality of cut roses during transportation and storage. Ethylene-responsive factors (ERFs) are key nodes in ethylene signaling, but the molecular mechanism underlying ERFs regulated flower senescence is not well understood. We addressed this issue in the present study by focusing on RhERF3 from Rosa hybrida, an ERF identified in a previous transcriptome analysis of ethylene-treated rose flowers. Expression of RhERF3 was strongly induced by ethylene during rose flower senescence. Transient silencing of RhERF3 delayed flower senescence, whereas overexpression (OE) accelerated the process. RNA sequencing analysis of RhERF3 OE and pSuper vector control samples identified 13,214 differentially expressed genes that were mostly related to metabolic process and plant hormone signal transduction. Transient activation and yeast one-hybrid assays demonstrated that RhERF3 directly bound the promoter of the 9-cis-epoxycarotenoid dioxygenase (RhNCED1) gene and activated gene expression. Thus, a RhERF3/RhNCED1 axis accelerates rose flower senescence.

Automated summary

In this study, we focused on the ethylene-responsive factor RhERF3 identified in ethylene-treated rose flowers, and found that RhERF3 expression is strongly induced by ethylene during rose flower senescence. Transient silencing and overexpression of RhERF3 revealed its role in regulating the process of rose flower senescence. RNA sequencing analysis showed that RhERF3 is mainly related to metabolic processes and plant hormone signal transduction pathways.