Development of a Whole-Cell System Based on the Use of Genetically Modified Protoplasts to Detect Nickel Ions in Food Matrices.

Heavy metals are dangerous contaminants that constitute a threat to human health because they persist in soils and are easily transferred into the food chain, causing damage to human health. Among heavy metals, nickel appears to be one of the most dangerous, being responsible for different disorders. Public health protection requires nickel detection in the environment and food chains. Biosensors represent simple, rapid, and sensitive methods for detecting nickel contamination. In this paper, we report on the setting up a whole-cell-based system, in which protoplasts, obtained from Nicotiana tabacum leaves, were used as transducers to detect the presence of heavy metal ions and, in particular, nickel ions. Protoplasts were genetically modified with a plasmid containing the Green Fluorescent Protein reporter gene (GFP) under control of the promoter region of a sunflower gene coding for a small Heat Shock Protein (HSP). Using this device, the presence of heavy metal ions was detected. Thus, the possibility of using this whole-cell system as a novel tool to detect the presence of nickel ions in food matrices was assessed.

CiXTH29 and CiLEA4 Role in Water Stress Tolerance in Cichorium intybus Varieties.

Drought causes massive crop quality and yield losses. Limiting the adverse effects of water deficits on crop yield is an urgent goal for a more sustainable agriculture. With this aim, six chicory varieties were subjected to drought conditions during seed germination and at the six week-old plant growth stage, in order to identify some morphological and/or molecular markers of drought resistance. Selvatica, Zuccherina di Trieste and Galatina varieties, with a high vegetative development, showed a major germination index, greater seedling development (6 days of growth) and a greater dehydration resistance (6 weeks of growth plus 10 days without water) than the other ones (Brindisina, Esportazione and Rossa Italiana). Due to the reported involvement, in the abiotic stress response, of xyloglucan endotransglucosylase/hydrolases (XTHs) and late embryogenesis abundant (LEA) multigene families, XTH29 and LEA4 expression profiles were investigated under stress conditions for all analyzed chicory varieties. We showed evidence that chicory varieties with high CiXTH29 and CiLEA4 basal expression and vegetative development levels better tolerate drought stress conditions than varieties that show overexpression of the two genes only in response to drought. Other specific morphological traits characterized almost all chicory varieties during dehydration, i.e., the appearance of lysigen cavities and a general increase of the amount of xyloglucans in the cell walls of bundle xylem vessels. Our results highlighted that high CiXTH29 and CiLEA4 basal expression, associated with a high level of vegetative growth, is a potential marker for drought stress tolerance.

Expression of Exogenous GFP-CesA6 in Tobacco Enhances Cell Wall Biosynthesis and Biomass Production.

Improved cellulose biosynthesis and plant biomass represent important economic targets for several biotechnological applications including bioenergy and biofuel production. The attempts to increase the biosynthesis of cellulose by overexpressing CesAs proteins, components of the cellulose synthase complex, has not always produced consistent results. Analyses of morphological and molecular data and of the chemical composition of cell walls showed that tobacco plants (F31 line), stably expressing the Arabidopsis CesA6 fused to GFP, exhibits a "giant" phenotype with no apparent other morphological aberrations. In the F31 line, all evaluated growth parameters, such as stem and root length, leaf size, and lignified secondary xylem, were significantly higher than in wt. Furthermore, F31 line exhibited increased flower and seed number, and an advance of about 20 days in the anthesis. In the leaves of F31 seedlings, the expression of primary CesAs (NtCesA1, NtCesA3, and NtCesA6) was enhanced, as well as of proteins involved in the biosynthesis of non-cellulosic polysaccharides (xyloglucans and galacturonans, NtXyl4, NtGal10), cell wall remodeling (NtExp11 and XTHs), and cell expansion (NtPIP1.1 and NtPIP2.7). While in leaves the expression level of all secondary cell wall CesAs (NtCesA4, NtCesA7, and NtCesA8) did not change significantly, both primary and secondary CesAs were differentially expressed in the stem. The amount of cellulose and matrix polysaccharides significantly increased in the F31 seedlings with no differences in pectin and hemicellulose glycosyl composition. Our results highlight the potentiality to overexpress primary CesAs in tobacco plants to enhance cellulose synthesis and biomass production.

Drought Stress Pre-Treatment Triggers Thermotolerance Acquisition in Durum Wheat.

Durum wheat is strongly affected by climatic constraints such as high temperatures and drought, which frequently lead to yield reduction. Damages due to high temperatures are related to plant thermotolerance, a trait determined by two components: basal and acquired thermotolerance. In this study, the effect of drought and heat stress imposed singularly or sequentially was investigated in ten durum wheat cultivars (cvs) at the physiological and molecular level. The traits analyzed were cell membrane stability, relative water content, proline content, and expression level of several genes for heat shock proteins (HSPs). Our results indicate that drought priming can induce the acquisition of thermotolerance in most cultivars already classified as able to acquire thermotolerance by heat pre-treatment. Proline accumulation was correlated to cell membrane stability, meaning that the most thermotolerant cvs were able to accumulate higher levels of proline. Acquired thermotolerance is also due to the activation of HSP gene expression; similarly, pre-treatment with water stress was able to activate HSPs expression. The results reported indicate that water stress plays an important role in inducing thermotolerance, comparable to mild heat stress pre-treatment. This is the first report on the effect of drought stress on the acquisition of thermotolerance.

A stress-related transcription factor belonging to the YL-1 family is differently regulated in durum wheat cultivars differing in drought sensitivity.

The Mediterranean area is characterised by unfavorable environmental conditions such as heat stress and drought responsible for yield loss of crops like durum wheat, widely cultivated in this area. The response of plants to stressing environments is mediated by activation of a complex gene network, strictly related to the genetic background. Among the genes induced by drought, those coding for proteins acting as key regulators of signal transduction are of great interest. Characterization of these genes is a crucial point to understand their potential roles in plant stress response, also in view of their possible use in molecular breeding. In this work we have characterised a Triticum durum gene, named TdDRG1, in two commercial cultivars, Primadur and Svevo, differing for drought stress resistance. TdDRG1 codes for a putative transcription factor belonging to the VPS72/YL-1 family, highly conserved in plants and animals. The expression analysis indicates that this gene is expressed at higher level in roots of the resistant cultivar Svevo, than in the susceptible Primadur. The gene structure was determined in both cultivars and the regulatory activity of 5' upstream regions was analyzed by transient expression analysis using tobacco protoplasts. Dissimilar expression level of TdDRG1 in the two cultivars can be explained by the differences observed in gene structure. In particular, differences in 5' upstream regions could account for contrasting ability to cope with drought of the two cultivars. The data obtained in this study provide indications for further insight into the molecular basis of differences in drought stress response.

New gene functions are involved in the thermotolerance of the wild wheat relative Aegilops umbellulata.

Wheat is one of the most important food crops in the world for human consumption, like all plants it is exposed to environmental stresses including high temperatures. The deleterious effect of high temperatures negatively affects plant growth and development, leading to reduced viability and yield. These effects can be reduced by improvement of thermotolerance through innovative breeding strategies, based on the expansion of the genetic pool available, by exploring important genetic functions from wheat wild progenitors. Improving the genetic thermotolerance characteristics of wheat requires greater understanding of genetic bases of thermotolerance, through identification of high temperature stress related genes. A good source of new useful alleles is given by Aegilops species characterized by thermotolerant habits. In this study we have classified as thermotolerant or thermosensitive, on the basis of physiologic tests, some accessions of wheat wild relative species belonging to Aegilops and Triticum genera. A thermotolerant accession of Aegilops umbellulata (AUM5) was selected, subjected to different thermal treatments and analyzed at transcriptional level. By differential display reverse transcriptase polymerase chain reaction (DDRT-PCR), we investigated modulation of gene expression elicited by heat treatments. This approach allowed the identification of various transcript-derived fragments (TDFs) produced by AUM5 in response to different thermal treatments. The functions of the inducible unique genes in the molecular determination of thermotolerance process are discussed.

Molecular Effects of Xylella fastidiosa and Drought Combined Stress in Olive Trees.

Due to global climate change, complex combinations of stresses are expected to occur, among which the interaction between pathogens and drought stress may have a significant effect on growth and yield. In this study, the Xylella fastidiosa (Xf)-resistant cultivar Leccino and the susceptible one Cellina di Nardò were subjected to (a) individual drought stress, (b) Xf infection and (c) combination of both stress conditions. Here we report the physiological response to stresses in water content in leaves and the modulation in the expression level of seven genes responsive to plant water status and pathogen infection. In Xf-resistant plants, higher expression levels are reported for genes belonging to ROS-scavenging systems and for genes involved in pathogen stress (pathogenesis-related, PR, and leucine-rich repeat genes, LRR-RLK). However, PR and LRR-RLK were not further induced by water deficit. Interestingly, the genes related to drought response (aquaporin, PIP2.1, dehydration responsive element binding, DREB, and dehydrin, DHN), which induction was higher in Cellina di Nardò compared to Leccino during drought stress, was poorly induced in Xf-susceptible plants when Xf occur. Conversely, DHN was induced by Xf presence in Leccino. These results were consistent with observations on water content. Indeed, response was similar in Leccino regardless kind of stress or combination, whereas a strong reduction was observed in Xf-susceptible plants infected by Xf or in presence of combined stresses. Thus, the reported findings indicate that resistance of Leccino to Xf could be linked to its lower resistance to water stress, probably leading to the activation of alternative defense pathways that support the plant in Xf response.

Exploitation of Prunus mahaleb fruit by fermentation with selected strains of Lactobacillus plantarum and Saccharomyces cerevisiae.

The organoleptic attributes of Prunus mahaleb, a fruit representing a new source of bioactive compounds, are so pronounced that it can be consider non-edible. This study was designed to evaluate the acceptance of P. mahaleb fruits after fermentation with different Saccharomyces cerevisiae and Lactobacillus plantarum protechnological strains. Four different bacterial and one yeast strains, as single or mixed starter formulation, were used to inoculate an aqueous suspension of P. mahaleb fruits. The fermented fruits and fermentation broths were subjected to physico-chemical characterization and the organoleptic properties of both samples were also assessed by a hedonic panel. The obtained results indicated that all the employed strains were able to grow and to ferment the matrix. However, the mixed starter FG69 + Li180-7 (L. plantarum/S. cerevisiae) had the best impact on sensory characteristics of P. mahaleb fruit and fermented medium. The adopted protocol allowed us to attain edible fruits and a new fermented non-dairy drink with valuable probiotic health-promoting properties. In our knowledge, this is the first study concerning the exploitation of P. mahaleb fruits. This investigation confirmed the potential of yeasts and lactic acid bacteria co-inoculation in the design of starter tailored for this kind of food applications.

Salvia clandestina L.: unexploited source of danshensu.

We report the characterisation of Salvia clandestina L. shoots and roots aqueous extract using HPLC-ESI/MS-TOF. Among the 29 compounds detected, we observed the presence of danshensu (3-(3,4-dihydroxy-phenyl) 2-hydroxy-propinic acid), a powerful antioxidant and a cardio-protective agent. The danshensu content found in the shoots of S. clandestina was considerable (4.96 mg g-1 DW) if compared with previous studies on S. miltiorrhiza Bunge, the main source of this compound. We also determined the total phenolic concentration and we evaluated their antioxidant activity by ABTS, FRAP and Superoxide anion scavenging methods. All the three assays confirmed a greater antioxidant activity for the shoots in comparison to roots. S. clandestina shoots may represent a valuable and natural unexploited source of danshensu and other phenolic compounds, so that it may be useful for future applications in functional foods and pharmaceutical industries.

Activation of a gene network in durum wheat roots exposed to cadmium.

BACKGROUND: Among cereals, durum wheat (Triticum turgidum L. subsp. durum) accumulates cadmium (Cd) at higher concentration if grown in Cd-polluted soils. Since cadmium accumulation is a risk for human health, the international trade organizations have limited the acceptable concentration of Cd in edible crops. Therefore, durum wheat cultivars accumulating low cadmium in grains should be preferred by farmers and consumers. To identify the response of durum wheat to the presence of Cd, the transcriptomes of roots and shoots of Creso and Svevo cultivars were sequenced after a 50-day exposure to 0.5 µM Cd in hydroponic solution. RESULTS: No phytotoxic effects or biomass reduction was observed in Creso and Svevo plants at this Cd concentration. Despite this null effect, cadmium was accumulated in root tissues, in shoots and in grains suggesting a good cadmium translocation rate among tissues. The mRNA sequencing revealed a general transcriptome rearrangement after Cd treatment and more than 7000 genes were found differentially expressed in root and shoot tissues. Among these, the up-regulated genes in roots showed a clear correlation with cadmium uptake and detoxification. In particular, about three hundred genes were commonly up-regulated in Creso and Svevo roots suggesting a well defined molecular strategy characterized by the transcriptomic activation of several transcription factors mainly belonging to bHLH and WRKY families. bHLHs are probably the activators of the strong up-regulation of three NAS genes, responsible for the synthesis of the phytosiderophore nicotianamine (NA). Moreover, we found the overall up-regulation of the methionine salvage pathway that is tightly connected with NA synthesis and supply the S-adenosyl methionine necessary for NA biosynthesis. Finally, several vacuolar NA chelating heavy metal transporters were vigorously activated. CONCLUSIONS: In conclusion, the exposure of durum wheat to cadmium activates in roots a complex gene network involved in cadmium translocation and detoxification from heavy metals. These findings are confident with a role of nicotianamine and methionine salvage pathway in the accumulation of cadmium in durum wheat.

Early Ongoing Speciation of Ogataea uvarum Sp. Nov. Within the Grape Ecosystem Revealed by the Internal Variability Among the rDNA Operon Repeats.

A yeast strain was isolated during a study on vineyard-associated yeast strains from Apulia in Southern Italy. ITS and LSU D1/D2 rDNA sequences showed this strain not to belong to any known species and was described as the type strain of Ogataea uvarum sp. nov., a close relative of O. philodendri. Several secondary peaks appeared in the sequences, suggesting internal heterogeneity among the copies of the rDNA. This hypothesis was tested by sequencing single clones of the marker region. The analyses showed different levels of variability throughout the operon with differences between the rRNA encoding genes and the internally transcribed regions. O. uvarum and O. philodendri share high frequency variants, i.e., variants frequently found in many clones, whereas there is a large variability of the low frequency polymorphisms, suggesting that the mechanism of homogenization is more active with the former than with the latter type of variation. These findings indicate that low frequency variants are detected in Sanger sequencing as secondary peaks whereas in Next Generation Sequencing (NGS) of metagenomics DNA would lead to an overestimate of the alpha diversity. For the first time in our knowledge, this investigation shed light on the variation of the copy number of the rDNA cistron during the yeast speciation process. These polymorphisms can be used to investigate on the processes occurring in these taxonomic markers during the separation of fungal species, it being a genetic process highly frequent in the complex microbial ecosystem existing in grape, must and wine.

Td4IN2: A drought-responsive durum wheat (Triticum durum Desf.) gene coding for a resistance like protein with serine/threonine protein kinase, nucleotide binding site and leucine rich domains.

Wheat, the main food source for a third of world population, appears strongly under threat because of predicted increasing temperatures coupled to drought. Plant complex molecular response to drought stress relies on the gene network controlling cell reactions to abiotic stress. In the natural environment, plants are subjected to the combination of abiotic and biotic stresses. Also the response of plants to biotic stress, to cope with pathogens, involves the activation of a molecular network. Investigations on combination of abiotic and biotic stresses indicate the existence of cross-talk between the two networks and a kind of overlapping can be hypothesized. In this work we describe the isolation and characterization of a drought-related durum wheat (Triticum durum Desf.) gene, identified in a previous study, coding for a protein combining features of NBS-LRR type resistance protein with a S/TPK domain, involved in drought stress response. This is one of the few examples reported where all three domains are present in a single protein and, to our knowledge, it is the first report on a gene specifically induced by drought stress and drought-related conditions, with this particular structure.

Cadmium Concentration in Grains of Durum Wheat (Triticum turgidum L. subsp. durum).

Heavy metal excess in soil represents a critical problem for crop productivity. Among these pollutants, cadmium (Cd) is one of the most dangerous in terms of food-chain contamination. Two durum wheat near-isogenic lines (NILs) and 12 commercial varieties (cultivars Arcangelo, Aureo, Aziziah, Cappelli, Cirillo, Creso, Iride, Maestrale, Parsifal, Russello, Strongfield, and Svevo) of durum wheat were exposed to a nontoxic level of Cd to evaluate its concentration in grains, roots, and shoots, as well as effects on biomass production. Cultivar Iride showed the most interesting behavior because it stored large amounts of Cd in the roots, preventing its translocation to grains. On the contrary, Cirillo and Svevo genotypes were characterized by a high Cd concentration in the grains. Furthermore, a molecular characterization employing the ScOPC20 marker associated with the Cd uptake locus has shown the absence of the expected fragment in the Iride variety and in other varieties characterized by low Cd concentration, as well as the presence of it in high Cd-accumulating cultivars.

Drought and Heat Differentially Affect XTH Expression and XET Activity and Action in 3-Day-Old Seedlings of Durum Wheat Cultivars with Different Stress Susceptibility.

Heat and drought stress have emerged as major constraints for durum wheat production. In the Mediterranean area, their negative effect on crop productivity is expected to be exacerbated by the occurring climate change. Xyloglucan endotransglucosylase/hydrolases (XTHs) are chief enzymes in cell wall remodeling, whose relevance in cell expansion and morphogenesis suggests a central role in stress responses. In this work the potential role of XTHs in abiotic stress tolerance was investigated in durum wheat. The separate effects of dehydration and heat exposure on XTH expression and its endotransglucosylase (XET) in vitro activity and in vivo action have been monitored, up to 24 h, in the apical and sub-apical root regions and shoots excised from 3-day-old seedlings of durum wheat cultivars differing in stress susceptibility/tolerance. Dehydration and heat stress differentially influence the XTH expression profiles and the activity and action of XET in the wheat seedlings, depending on the degree of susceptibility/tolerance of the cultivars, the organ, the topological region of the root and, within the root, on the gradient of cell differentiation. The root apical region was the zone mainly affected by both treatments in all assayed cultivars, while no change in XET activity was observed at shoot level, irrespective of susceptibility/tolerance, confirming the pivotal role of the root in stress perception, signaling, and response. Conflicting effects were observed depending on stress type: dehydration evoked an overall increase, at least in the apical region of the root, of XET activity and action, while a significant inhibition was caused by heat treatment in most cultivars. The data suggest that differential changes in XET action in defined portions of the root of young durum wheat seedlings may have a role as a response to drought and heat stress, thus contributing to seedling survival and crop establishment. A thorough understanding of the mechanisms underlying these variations could represent the theoretical basis for implementing breeding strategies to develop new highly productive hybrids adapted to future climate scenarios.

Different stress responsive strategies to drought and heat in two durum wheat cultivars with contrasting water use efficiency.

BACKGROUND: Durum wheat often faces water scarcity and high temperatures, two events that usually occur simultaneously in the fields. Here we report on the stress responsive strategy of two durum wheat cultivars, characterized by different water use efficiency, subjected to drought, heat and a combination of both stresses. RESULTS: The cv Ofanto (lower water use efficiency) activated a large set of well-known drought-related genes after drought treatment, while Cappelli (higher water use efficiency) showed the constitutive expression of several genes induced by drought in Ofanto and a modulation of a limited number of genes in response to stress. At molecular level the two cvs differed for the activation of molecular messengers, genes involved in the regulation of chromatin condensation, nuclear speckles and stomatal closure. Noteworthy, the heat response in Cappelli involved also the up-regulation of genes belonging to fatty acid ß-oxidation pathway, glyoxylate cycle and senescence, suggesting an early activation of senescence in this cv. A gene of unknown function having the greatest expression difference between the two cultivars was selected and used for expression QTL analysis, the corresponding QTL was mapped on chromosome 6B. CONCLUSION: Ofanto and Cappelli are characterized by two opposite stress-responsive strategies. In Ofanto the combination of drought and heat stress led to an increased number of modulated genes, exceeding the simple cumulative effects of the two single stresses, whereas in Cappelli the same treatment triggered a number of differentially expressed genes lower than those altered in response to heat stress alone. This work provides clear evidences that the genetic system based on Cappelli and Ofanto represents an ideal tool for the genetic dissection of the molecular response to drought and other abiotic stresses.

Role of the C-terminus of Pleurotus eryngii Ery4 laccase in determining enzyme structure, catalytic properties and stability.

The ERY4 laccase gene of Pleurotus eryngii is not biologically active when expressed in yeast. To explain this finding, we analysed the role of the C-terminus of Ery4 protein by producing a number of its different mutant variants. Two different categories of ERY4 mutant genes were produced and expressed in yeast: (i) mutants carrying C-terminal deletions and (ii) mutants carrying different site-specific mutations at their C-terminus. Investigation of the catalytic properties of the recombinant enzymes indicated that each novel variant acquired different affinities and catalytic activity for various substrates. Our results highlight that C-terminal processing is fundamental for Ery4 laccase enzymatic activities allowing substrate accessibility to the enzyme catalytic core. Apparently, the last 18 amino acids in the C-terminal end of the Ery4 laccase play a critical role in enzyme activity, stability and kinetic and, in particular biochemical and structural data indicate that the K532 residue is fundamental for enzyme activation. These studies shed light on the structure/function relationships of fungal laccases and will enhance the development of biotechnological strategies for the industrial exploitation of these enzymes.

Novel durum wheat genes up-regulated in response to a combination of heat and drought stress.

We report the effect of heat, drought and combined stress on the expression of a group of genes that are up-regulated under these conditions in durum wheat (Triticum turgidum subsp. durum) plants. Modulation of gene expression was studied by cDNA-AFLP performed on RNAs extracted from flag leaves. By this approach, we identified several novel durum wheat genes whose expression is modulated under different stress conditions. We focused on a group of hitherto undescribed up-regulated genes in durum wheat, among these, 7 are up-regulated by heat, 8 by drought stress, 15 by combined heat and drought stress, 4 are up-regulated by both heat and combined stress, and 3 by both drought and combined stress. The functional characterization of these genes will provide new data that could help the developing of strategies aimed at improving durum wheat tolerance to field stress.

Identification of candidate genes associated with senescence in durum wheat (Triticum turgidum subsp. durum) using cDNA-AFLP.

Senescence is an integrated response of plants to various internal (developmental) and external (environmental) signals. It is a highly regulated process leading eventually to the death of cells, single organs such as leaves, or even whole plants. In cereals, which are monocarpic plants, senescence represents the final stage of development. In order to study senescence in durum wheat (Triticum turgidum subsp. durum), a cDNA-AFLP analysis was performed. The transcription profiles of plants at different developmental stages (flowering and senescent) were compared. About 2000 cDNA fragments, ranging in size from 160 to 1900 bp, were reproducibly detected. This allowed the identification of 57 differentially expressed cDNAs corresponding to genes belonging to different functional categories related to cellular metabolism, transcription, maintenance of DNA structure, transport and signal transduction. This paper reports the identification of novel durum wheat candidate genes involved in the senescence process, and provides new information about the senescence programme of this important crop species.

Molecular cloning and heterologous expression of a laccase gene from Pleurotus eryngii in free and immobilized Saccharomyces cerevisiae cells.

A full length cDNA encoding an extracellular laccase was isolated by reverse transcription polymerase chain reaction from the mycelia of the mushroom Pleurotus eryngii. The isolated sequence, denoted Ery3, encodes for a mature laccase isoenzyme of 531 amino acid residues with a predicted molecular weight of 56.6 kDa. All sequence motifs, being the signature sequences used to identify the laccases, were found in the Ery3 protein sequence. The Ery3 cDNA was expressed in Saccharomyces cerevisiae and the effects of copper concentration and cultivation temperature were investigated. S. cerevisiae cells were immobilized in calcium alginate gel and the optimal immobilization parameters for the enhanced production of laccase were determined. The immobilization was most effective with 3% sodium alginate, 0.1 M calcium chloride and an initial biomass of 4.5 x 10(8) cells. The enzyme yield obtained with immobilized cells (139 mU ml(-1)) showed a 1.6-fold increase compared to the highest yield obtained with free cells. The alginate beads showed good stability and retained 84% capacity of enzyme production after seven repeated cycles of batch fermentation. The immobilization system proved to increase the proteolytic stability of the recombinant Ery3 protein. To our knowledge, this is the first report on S. cerevisiae whole-cell immobilization for recombinant laccase production.

Four members of the HSP101 gene family are differently regulated in Triticum durum Desf.

Heat shock proteins play an essential role in preventing deleterious effects of high temperatures. In many plants, HSP101 has a central role in heat stress survival. We report the isolation and characterization of four cDNAs corresponding to different members of the durum wheat HSP101 gene family. Expression analysis revealed differences in their induction. Accordingly, durum wheat HSP101 genes are differently regulated, therefore having distinct roles in stress response and thermotolerance acquisition. These findings are important for further dissection of the molecular mechanisms underlying the stress response and for understanding the functions of the HSP101 family members. This information could be important for the exploitation of specific alleles in marker assisted selection for abiotic stress resistance.