JcLEA, a Novel LEA-Like Protein from Jatropha curcas, Confers a High Level of Tolerance to Dehydration and Salinity in Arabidopsis thaliana

Jing Liang,Yuanjie Jin,Mingqi Zhou,Xin Zhou,Juan Lin,Ming Xu,Haibing Yang

doi:10.1371/journal.pone.0083056

Abstract

Jatropha curcas L. is a highly drought and salt tolerant plant species that is typically used as a traditional folk medicine and biofuel crop in many countries. Understanding the molecular mechanisms that underlie the response to various abiotic environmental stimuli, especially to drought and salt stresses, in J. curcas could be important to crop improvement efforts. In this study, we cloned and characterized the gene for a late embryogenesis abundant (LEA) protein from J. curcas that we designated JcLEA. Sequence analyses showed that the JcLEA protein belongs to group 5, a subgroup of the LEA protein family. In young seedlings, expression of JcLEA is significantly induced by abscisic acid (ABA), dehydration, and salt stress. Subcellular localization analysis shows that that JcLEA protein is distributed in both the nucleus and cytoplasm. Moreover, based on growth status and physiological indices, the overexpression of JcLEA in transgenic Arabidopsis plants conferred increased resistance to both drought and salt stresses compared to the WT. Our data suggests that the group 5 JcLEA protein contributes to drought and salt stress tolerance in plants. Thus, JcLEA is a potential candidate gene for plant genetic modification.

Highlights

Water and ion concentrations in soil are important abiotic elements for living organisms
The late embryogenesis abundant (LEA) proteins are a family of hydrophilic proteins that are presumed to play a protective role during exposure to different abiotic stresses
HVA1 from Hordeum vulgare, belonging to group 3, confers increased drought tolerance in wheat and rice [50,51], and enhanced drought, salinity, and cold tolerance when expressed in mulberry [52]

Summary

Introduction

Water and ion concentrations in soil are important abiotic elements for living organisms. Plants are sessile organisms that are exposed to seasonal and local environmental variations, and their survival and growth are strongly influenced by local stress factors. The late embryogenesis abundant (LEA) proteins are involved in one type of selfprotection mechanism. LEA proteins belong to a large protein family that is closely associated with resistances to abiotic stresses, especially to drought, in a range of organisms [2]. LEA proteins mainly accumulate in the late stages of embryogenesis in plant seeds under dehydration stress [5], and have been found in bacteria [9], slime molds [10], nematodes [11,12,13,14,15], fungi [16], and humans [17]

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Results

Conclusion