Ethylene and the regulation of plant development

Abstract

Often considered an 'aging' hormone due to its role in accelerating such developmental processes as ripening, senescence, and abscission, the plant hormone ethylene also regulates many aspects of growth and development throughout the life cycle of the plant. Multiple mechanisms have been identified by which transcriptional output from the ethylene signaling pathway can be tailored to meet the needs of particular developmental pathways. Of special interest is the report by Lumba et al. in BMC Biology on how vegetative transitions are regulated through the effect of the transcription factor FUSCA3 on ethylene-controlled gene expression, providing an elegant example of how hormonal control can be integrated into a developmental pathway.

Figure 1

Ethylene signal transduction and the control of juvenile to adult phase transitions in the leaf. The pathway for ethylene signal transduction involves positive and negative regulators that culminate in transcriptional regulation by the EIN3-like family of transcription factors. Among the ethylene-responsive genes are some that encode additional transcription factors such as those of the ethylene response factor (ERF) and ethylene response DNA-binding factor (EDF) families. The pharmacological agents aminoethoxyvinylglycine (AVG) and silver can be used to inhibit ethylene responses through their ability to target ethylene biosynthesis or the receptors, respectively. One effect of ethylene is to stimulate the juvenile to adult phase transition of leaves. The transcription factor FUS3 negatively regulates the effects of ethylene on this developmental process. The juvenile to adult leaf morphology series shown is from Figure 3A in Lumba et al. [2].