Role of Ethylene Response Transcription Factor (ERF) and Its Regulation in Response to Stress Encountered by Plants

Plants are nonmotile and are easily affected by both biotic and abiotic stresses. Plants have evolved themselves at both cellular and molecular level to fight against stress. Transcription factors are important among the stress-responsive genes, and their protein products are known to regulate the expression of other stress-responsive genes via binding to the regulatory elements. Among the plant transcription factors, ethylene response factor (ERF) is one of the largest subfamilies of Apetala2 (AP2)/ERF transcription factor family and is characterized with single AP2 domain. ERFs are a double-edged sword; though most of the ERFs are activators of stress-responsive genes, certain ERF could act as repressor, and this phenomenon of ERF has been well discussed in this review. Further, the expression of ERFs may be ethylene dependent or independent and is regulated by feedback mechanism. Apart from above regulation mechanism, expressions of ERFs are post-transcriptionally regulated by microRNAs (miRNAs), and miRNA expressions are in turn regulated by ERFs. The present review highlights the importance of ERFs in plant stress management and complexity in regulation of ERF expression in response to various stresses.