Isolation and characterization of an atypical LEA gene (IpLEA) from Ipomoea pes-caprae conferring salt/drought and oxidative stress tolerance

Abstract

Late embryogenesis abundant (LEA) proteins belong to a large family that exists widely in plants and is mainly involved in desiccation processes during plant development or in the response to abiotic stresses. Here, we reported on an atypical LEA gene (IpLEA) related to salt tolerance from Ipomoea pes-caprae L. (Convolvulaceae). Sequence analysis revealed that IpLEA belongs to the LEA_2 (PF03168) group. IpLEA was shown to have a cytoplasmic localization pattern. Quantitative reverse transcription PCR analysis showed that IpLEA was widely expressed in different organs of the I. pes-caprae plants, and the expression levels increased following salt, osmotic, oxidative, freezing, and abscisic acid treatments. Analysis of the 1,495 bp promoter of IpLEA identified distinct cis-acting regulatory elements involved in abiotic stress. Induction of IpLEA improved Escherichia coli growth performance compared with the control under abiotic stresses. To further assess the function of IpLEA in plants, transgenic Arabidopsis plants overexpressing IpLEA were generated. The IpLEA-overexpressing Arabidopsis seedlings and adult plants showed higher tolerance to salt and drought stress than the wild-type. The transgenic plants also showed higher oxidative stress tolerance than the wild-type Arabidopsis. Furthermore, the expression patterns of a series of stress-responsive genes were affected. The results indicate that IpLEA is involved in the plant response to salt and drought, probably by mediating water homeostasis or by acting as a reactive oxygen species scavenger, thereby influencing physiological processes under various abiotic stresses in microorganisms and plants.

RNA-sequencing analysis revealed genes associated drought stress responses of different durations in hexaploid sweet potato

“…These genes have a major role in detoxification of ROS in the plant cell, which is extremely harmful as it causes lipid oxidation, DNA damage, and apoptosis. In agreement with our study, the role of protein detoxification has been documented in many plant species, i.e., Ipomoea batatas 18,88 , Ipomoea pes-caprae 89 , Arabidopsis thaliana 90 , Nicotiana tabacum 91 , Oryza sativa L. 92 and Solanum lycopersicum 93 . In addition, TSA genes are involved in the detoxification of reactive oxygen species (ROS), reactive sulfur species (RSS), and reactive nitrogen species (RNS).…”

Plant Group II LEA Proteins: Intrinsically Disordered Structure for Multiple Functions in Response to Environmental Stresses

“…In this review, novel insights related to DHNs were generated that characterized their functional properties under the stress environment, as it is crucial to have an extensive understanding about their biochemical, physiological, and biological functions in plant stress management. A number of transgenic approaches have indicated that overexpression of group II LEA proteins in a wide range of plant species improves abiotic stress resistance [9].…”

“…Group II LEA proteins were initially found in developing cotton (Gossypium hirsutum) embryos and are expressed in gymnosperms and angiosperms ubiquitously [8]. A positive association between the accumulation of group II LEA proteins and environmental stresses such as drought, heat, freezing, and salinity has been outlined in a number of studies [9]. However, in relation to contemporary genomics, these studies need to be reviewed and necessitate the generation of additional important structural, physicochemical, molecular, and functional characterization of group II LEA proteins.…”

What Do We Know About the Genetic Basis of Seed Desiccation Tolerance and Longevity?

“…Interestingly, LEA-like proteins are also found in a variety of organisms, such as anhydrobiotic nematodes [111,112], brine shrimp [113], rotifers [114,115], and some bacterial species [108]. Although LEAs were first described in embryonic tissues, thirty years of intensive research showed that the expression of LEA genes is also significantly induced in vegetative organs (i.e., callus, flowers, roots, leaves, buds) under abiotic stresses such as desiccation, salinity, and cold [116][117][118][119][120].…”