Introgression of SbERD4 Gene Encodes an Early-Responsive Dehydration-Stress Protein That Confers Tolerance against Different Types of Abiotic Stresses in Transgenic Tobacco.

Rajesh Kumar Jha,Avinash Mishra

doi:10.3390/cells11010062

Abstract

Salicornia brachiata is an extreme halophyte that commonly grows on marsh conditions and is also considered a promising resource for drought and salt-responsive genes. To unveil a glimpse of stress endurance by plants, it is of the utmost importance to develop an understanding of stress tolerance mechanisms. ‘Early Responsive to Dehydration’ (ERD) genes are defined as a group of genes involved in stress tolerance and the development of plants. To increase this understanding, parallel to this expedited thought, a novel SbERD4 gene was cloned from S. brachiata, characterized, and functionally validated in the model plant tobacco. The study showed that SbERD4 is a plasma-membrane bound protein, and its overexpression in tobacco plants improved salinity and osmotic stress tolerance. Transgenic plants showed high relative water, chlorophylls, sugars, starch, polyphenols, proline, free amino acids, and low electrolyte leakage and H2O2 content compared to control plants (wild type and vector control) under different abiotic stress conditions. Furthermore, the transcript expression of antioxidant enzyme encoding genes NtCAT, NtSOD, NtGR, and NtAPX showed higher expression in transgenic compared to wild-type and vector controls under varying stress conditions. Overall, the overexpression of a novel early responsive to dehydration stress protein 4-encoding gene (SbERD4) enhanced the tolerance of the plant against multiple abiotic stresses. In conclusion, the overexpression of the SbERD4 gene mitigates plant physiology by enduring stress tolerance and might be considered as a promising key gene for engineering salinity and drought stress tolerance in crops.

Highlights

Plants being sessile in nature evolved an adaptive mechanism to perceive, respond, and cope with adverse environmental conditions during their life cycle [1]
SbERD4 is a novel dehydration stress protein characterized from extreme halophytes Salicornia brachiata
Our finding demonstrated that the SbERD4 gene is localized in the plasma membrane, and its function is to improve stress tolerance in plants under different abiotic stress conditions

Summary

Introduction

Plants being sessile in nature evolved an adaptive mechanism to perceive, respond, and cope with adverse environmental conditions during their life cycle [1]. Abiotic stresses are major growth-limiting factors that adversely affect the overall plant growth and crop productivity in agriculture. Dehydration and salinity are the key restrictive factors limiting crop productivity in agriculture through alteration in metabolism and gene expression [2,3]. They affect the geographical distribution of the plant in nature as well as the growth and development at molecular and physio-biochemical levels that leads to food security [4]. In that pretext, improving salinity and drought resistance in crop plants has become an utmost important approach for safeguarding sustainable agriculture and food security [6,7,8]

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Results

Discussion

Conclusion