LeERF1 improves tolerance to drought stress in tomato (Lycopersicon esculentum) and activates downstream stress-responsive genes

Abstract

Ethylene responsive factors (ERFs) are important transcriptional regulators involved in plant responses to abiotic and biotic stresses. In this study, the function of the LeERF1 gene in sense- and antisense- LeERF1 transgenic tomato plants was analyzed. The results demonstrated that overexpression of LeERF1 in tomato plants enhanced tolerance to drought stress. The LeERF1-overexpressing transgenic plants maintained higher relative water content (RWC), free proline and soluble sugar levels, and showed lower malondialdehyde (MDA) level and electrolyte leakage under drought stress, compared with wild-type and antisense-LeERF1 tomato plants. Furthermore, overexpression of LeERF1 in tomato plants activated the expression of stress-related genes, including P5CS, LEA, ltpg2 and tdi-65. These results suggested that LeERF1 played a positive role in tolerance to drought stress.

Key words: LeERF1, drought tolerance, transcription factor, transgenic tomato.