PhERF6, interacting with EOBI, negatively regulates fragrance biosynthesis in petunia flowers

Abstract

In petunia, the production of volatile benzenoids/phenylpropanoids determines floral aroma, highly regulated by development, rhythm and ethylene. Previous studies identified several R2R3-type MYB trans-factors as positive regulators of scent biosynthesis in petunia flowers. Ethylene response factors (ERFs) have been shown to take part in the signal transduction of hormones, and regulation of metabolism and development processes in various plant species. Using virus-induced gene silencing technology, a negative regulator of volatile benzenoid biosynthesis, PhERF6, was identified by a screen for regulators of the expression of genes related to scent production. PhERF6 expression was temporally and spatially connected with scent production and was upregulated by exogenous ethylene. Up-/downregulation of the mRNA level of PhERF6 affected the expression of ODO1 and several floral scent-related genes. PhERF6 silencing led to a significant increase in the concentrations of volatiles emitted by flowers. Yeast two-hybrid, bimolecular fluorescence complementation and co-immunoprecipitation assays indicated that PhERF6 interacted with the N-terminus of EOBI, which includes two DNA binding domains. Our results show that PhERF6 negatively regulates volatile production in petunia flowers by competing for the binding of the c-myb domains of the EOBI protein with the promoters of genes related to floral scent.

PaACL silencing accelerates flower senescence and changes the proteome to maintain metabolic homeostasis in Petunia hybrida

“…To identify the function of the PaACLA1-A2 and PaACLB1-B2 genes, vectors were constructed to suppress the expression of these genes because we had already established a highly efficient VIGS system in petunia ‘Ultra’ ( Tan et al , 2014 ; Liu et al ., 2017 ). Approximately 30 days after petunia seedlings were infected, no visible change was observed in any single-gene-silenced plants compared with the controls.…”

An ETHYLENE RESPONSE FACTOR-MYB Transcription Complex Regulates Furaneol Biosynthesis by Activating QUINONE OXIDOREDUCTASE Expression in Strawberry

“…Recent research has provided evidence for interactions between AP2/ERF and MYB transcription factors in regulating other aspects of fruit quality, including texture (EjAP2-1 and EjMYB; Zeng et al, 2015) and color (PyERF3 and PyMYB114; Yao et al, 2017). A group VIII ERF also was shown recently to interact with an MYB to regulate floral scent production in petunia (Liu et al, 2017). In strawberry fruit, DOF, in combination with an MYB, has been reported to be involved in the regulation of eugenol production, and the identification of this second transcription factor (DOF) suggests that it is a good target in breeding for improved flavor (Molina-Hidalgo et al, 2017;Tieman, 2017).…”

PhDHS Is Involved in Chloroplast Development in Petunia

“…After 16–24 h, accumulation of the PhDHS-GFP fusion protein was detected in the cytoplasm and nucleus of petunia protoplasts (Figure 2A,B). To further verify the fluorescence signal of PhDHS-GFP fusion protein in the nucleus, we use EOBII-RFP (red fluorescent protein) as a nuclear marker given that it was previously demonstrated that EOBI are nuclear-localized MYB factors (Spitzer-Rimon et al, 2010, 2012; Liu et al, 2017). Localization of the PhDHS-GFP fusion protein was determined by visualization with a fluorescence microscope.…”