Ethylene response factor Sl-ERF.B.3 is responsive to abiotic stresses and mediates salt and cold stress response regulation in tomato.

Imen Klay,Mondher Bouzayen,Sadok Bouzid,Leila Riahi,Anne Bernadac,Julien Pirrello,Ameur Cherif

doi:10.1155/2014/167681

Abstract

Sl-ERF.B.3 (Solanum lycopersicum ethylene response factor B.3) gene encodes for a tomato transcription factor of the ERF (ethylene responsive factor) family. Our results of real-time RT-PCR showed that Sl-ERF.B.3 is an abiotic stress responsive gene, which is induced by cold, heat, and flooding, but downregulated by salinity and drought. To get more insight into the role of Sl-ERF.B.3 in plant response to separate salinity and cold, a comparative study between wild type and two Sl-ERF.B.3 antisense transgenic tomato lines was achieved. Compared with wild type, Sl-ERF.B.3 antisense transgenic plants exhibited a salt stress dependent growth inhibition. This inhibition was significantly enhanced in shoots but reduced in roots, leading to an increased root to shoot ratio. Furthermore, the cold stress essay clearly revealed that introducing antisense Sl-ERF.B.3 in transgenic tomato plants reduces their cell injury and enhances their tolerance against 14 d of cold stress. All these results suggest that Sl-ERF.B.3 gene is involved in plant response to abiotic stresses and may play a role in the layout of stress symptoms under cold stress and in growth regulation under salinity.

Highlights

Plants are frequently exposed to a plethora of stress conditions such as low temperature, salt, drought, flooding, heat, oxidative stress, and heavy metal toxicity
We further focused on Sl-ERF.B.3 role in vegetative growth regulation against salt stress by characterizing two SlERF.B.3 antisense transgenic tomato lines compared to wild type, and we discussed the Sl-ERF.B.3 role in the layout of shoot and root growth changes related to adaptive responses to salinity
In the second part of this work we focused on the tomato plant responses to salt and cold stresses

Summary

Introduction

Plants are frequently exposed to a plethora of stress conditions such as low temperature, salt, drought, flooding, heat, oxidative stress, and heavy metal toxicity. It has been estimated that abiotic stresses were the principal cause of decreasing the average yield of major crops by more than 50% [2] To confront such environmental aggressions, plants develop adaptive responses at physiological and molecular levels, which are specified to each stress condition [3]. A major event in response to stresses is the perception and transduction of stress signals through signaling components, which results in the activation of numerous stress-related genes [4] The products of these genes may participate in the generation of regulatory molecules like the plant hormones ethylene, abscisic acid (ABA), and salicylic acid (SA). The present study is the first to examine the expression patterns of the transcription factor gene Sl-ERF.B.3 (formerly called LeERF4) in tomato to determine its regulation in response to a variety of abiotic stress conditions (salinity, drought, flooding, heat, and cold) based on wild type tomato plants. We investigated Sl-ERF.B.3 antisense lines tolerance against cold treatment and Sl-ERF.B.3 role on cell membrane injury occurred during low temperature stress responses

Materials and Methods

Results and Discussion

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