Trehalose accumulation in rice plants confers high tolerance levels to different abiotic stresses. Proc Natl Acad Sci USA

Departments of Molecular Biology and Genetics, Plant Biology, and Horticulture, Cornell University, Ithaca, NY 14853, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 01/2003; 99(25):15898-903. DOI: 10.1073/pnas.252637799
Source: PubMed


Trehalose is a nonreducing disaccharide of glucose that functions as a compatible solute in the stabilization of biological structures under abiotic stress in bacteria, fungi, and invertebrates. With the notable exception of the desiccation-tolerant "resurrection plants," trehalose is not thought to accumulate to detectable levels in most plants. We report here the regulated overexpression of Escherichia coli trehalose biosynthetic genes (otsA and otsB) as a fusion gene for manipulating abiotic stress tolerance in rice. The fusion gene has the advantages of necessitating only a single transformation event and a higher net catalytic efficiency for trehalose formation. The expression of the transgene was under the control of either tissue-specific or stress-dependent promoters. Compared with nontransgenic rice, several independent transgenic lines exhibited sustained plant growth, less photo-oxidative damage, and more favorable mineral balance under salt, drought, and low-temperature stress conditions. Depending on growth conditions, the transgenic rice plants accumulate trehalose at levels 3-10 times that of the nontransgenic controls. The observation that peak trehalose levels remain well below 1 mgg fresh weight indicates that the primary effect of trehalose is not as a compatible solute. Rather, increased trehalose accumulation correlates with higher soluble carbohydrate levels and an elevated capacity for photosynthesis under both stress and nonstress conditions, consistent with a suggested role in modulating sugar sensing and carbohydrate metabolism. These findings demonstrate the feasibility of engineering rice for increased tolerance of abiotic stress and enhanced productivity through tissue-specific or stress-dependent overproduction of trehalose.

Download full-text


Available from: Leon Kochian
  • Source
    • "On the whole, our data suggest that employing two complementary approaches have increased the overall coverage of the differentially expressed genes that in turn has aided in filling crucial gaps in the abovementioned processes.Table 2) and down-regulated genes involved in cell wall metabolisms (Table S7; Figure 5). Trehalose is a nonreducing disaccharide that plays a major role in the stabilization of proteins and molecular structures during stress (Garg et al., 2002). Likewise, raffinose belongs to a family of oligosaccharides that accumulates during stress and acts as osmoprotectants (Unda et al., 2012). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Cotton bollworm, Helicoverpa armigera, is a major insect pest that feeds on cotton bolls causing extensive damage leading to crop and productivity loss. In spite of such a major impact, cotton plant response to bollworm infection is yet to be witnessed. In this context, we have studied the genomewide response of cotton bolls infested with boll worm using transcriptomic and proteomic approaches. Further, we have validated this data using semi-quantitative real-time PCR. Comparative analyses have revealed that 39% of the transcriptome and 35% of the proteome were differentially regulated during boll worm infestation. Around 36% of significantly regulated transcripts and 45% of differentially expressed proteins were found to be involved in signalling followed by redox regulation. Further analysis showed that defence-related stress hormones and their lipid precursors, transcription factors, signalling molecules, etc. were stimulated, whereas the growth-related counterparts were suppressed during boll worm infestation. Around 26% of the significantly up-regulated proteins were defence molecules, while >50% of the significantly down-regulated were related to photosynthesis and growth. Interestingly, the biosynthesis genes for synergistically regulated jasmonate, ethylene and suppressors of the antagonistic factor salicylate were found to be up-regulated, suggesting a choice among stress-responsive phytohormone regulation. Manual curation of the enzymes and TFs highlighted the components of retrograde signalling pathways. Our data suggest that a selective regulatory mechanism directs the reallocation of metabolic resources favouring defence over growth under boll worm infestation and these insights could be exploited to develop bollworm-resistant cotton varieties.
    Full-text · Article · Jan 2016 · Plant Biotechnology Journal
  • Source
    • "Therefore, it seems that StDREB1 and StDREB2 transcription factors may increase sugar biosynthesis to confer tolerance to drought stress in transgenic plants. These data corroborate those reported previously showing that sucrose and other simple sugars are efficient cryoprotectants stabilizing proteins and adjusting the osmotic pressure (Garg et al. 2002; Taji et al. 2002). Moreover, AtDREB1A can affect sugar metabolism in transgenic Arabidopsis which accumulates high levels of sucrose under both normal growth conditions and upon cold acclimation (Gilmour et al. 2000). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Ethylene-responsive element-binding factors (ERF) constitute one of the largest transcription factor families in plants. In this study, we describe the cloning and the characterization of ten cDNAs encoding ERF factors from potato. The alignment of their AP2/ERF (Apetala2/ethylene-responsive factor) domain led to the identification of six StERFs (Solanum tuberosum ERFs) and four StDREBs (dehydration responsive element binding). The phylogeny and the sequence characterization allowed the classification of these StERFs into five ERF families. Expression analysis by semi-quantitative RT-PCR of these genes revealed that most of them are induced by hormone treatment such as abscisic acid, ethephon, jasmonic acid and salicylic acid. However, salt stress induced the expression of all StDREB but only three StERF genes. These results suggest that these transcription factors are involved in salt stress response. The StDREB1 and StDREB2 genes showed strong increase in expression in response to drought stress. In an attempt to improve drought tolerance in potato, we overexpressed StDREB1 and StDREB2 in transgenic potato plants (S. tuberosum L. Group Tuberosum) cv. Belle de Fontenay (BF15) and Spunta, respectively. The level of drought tolerance of these transgenic lines was significantly greater than that of wild-type control plants as measured by relative water content H2O2 content, free proline and total soluble sugars. The results suggest that the StDREB1 and StDREB2 as AP2/ERF transcription factors may play dual roles in response to drought stress in potato.
    Full-text · Article · Oct 2015 · Plant Cell Tissue and Organ Culture
  • Source
    • "Plantshaveevolvedanarrayofmechanismsinresponsetoabioticstresses,suchashigh salt,drought,cold,andexcessiveosmoticpressure(Xiangetal.2007).Inresponse,many plantsaccumulatecompatibleosmolytes,suchasfreeproline(Kisoretal.2005)andfree sugar(Gargetal.2002;Gilmouretal.2000;GuptaandKaur2005;Tabuchietal.2004),to protecttheirsubcellularstructuresfromdamagebyadjustingintracellularosmotic potentials.Prolineexertsdiverseeffectsunderosmoticstressconditions,suchasstabilizing proteins,membranes,andsubcellularstructures(VanRensburgetal.1993),andprotecting "
    [Show abstract] [Hide abstract]
    ABSTRACT: The calcineurin B-like protein (CBL)-CBL-interacting protein kinase (CIPK) pathway is emerging as a major signaling pathway in plants. To understand the function of CIPK, the gene named BrCIPK1 from Brassica rapa were introduced into rice. Characterization of BrCIPK1 gene showed a 1982 bp, containing 1509 bp coding region and 502 amino acids. Green fluorescent protein (GFP)-tagged BrCIPK1 was observed exclusively in the cytoplasmic and peripheral regions in the plant cell. Gene expression showed that its messenger RNA (mRNA) transcription in B. rapa was differentially accumulated in the presence of cold, salinity, and drought, indicating its biological roles in multiple stress response pathways in plants. Furthermore, Ubi-1::BrCIPK1 rice lines showed significantly higher biomass, water content, and proline and free sugar content relative to those in the wild-type Gopum. The BrCIPK1 interacted with rice calcineurin B-like protein 1 and 5 (OsCBL1, OsCBL5), suggesting that it is activated by Ca2+-bound CBLs in the cytosol by calcium spiking and regulates its downstream target proteins in these regions to increase abiotic stress tolerance. The results imply that BrCIPK1 gene may be involved in stress adaptations through the activation of pyrroline-5-carboxylate synthase in the proline biosynthetic pathway. In this paper, a hypothetical mechanism of elevated tolerance to cold, drought, and salinity is presented.
    Full-text · Article · Sep 2015 · Plant Molecular Biology Reporter
Show more