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Dehydrin Gene (dehydrin + gene)
Selected AbstractsOverexpression of the acidic dehydrin WCOR410 improves freezing tolerance in transgenic strawberry leavesPLANT BIOTECHNOLOGY JOURNAL, Issue 5 2004Mario Houde Summary Progress in freezing tolerance (FT) improvement through plant breeding approaches has met with little success in the last 50 years. Engineering plants for greater FT through plant transformation is one possible way to reduce the damage caused by freezing. Here, we report an improvement of the selection procedure and the transfer of the wheat Wcor410a acidic dehydrin gene in strawberry. The encoded protein has previously been shown to be associated with the plasma membrane, and its level of accumulation has been correlated with the degree of FT in different wheat genotypes. The WCOR410 protein was expressed in transgenic strawberry at a level comparable with that in cold-acclimated wheat. Freezing tests showed that cold-acclimated transgenic strawberry leaves had a 5 °C improvement of FT over wild-type or transformed leaves not expressing the WCOR410 protein. However, no difference in FT was found between the different plants under non-acclimated conditions, suggesting that the WCOR410 protein needs to be activated by another factor induced during cold acclimation. These data demonstrate that the WCOR410 protein prevents membrane injury and greatly improves FT in leaves of transgenic strawberry. A better understanding of the limiting factors allowing its activation may open up the way for engineering FT in different plant organs, and may find applications for the cryopreservation of human tissues and organs. [source] Combinatorial interactions of multiple cis -elements regulating the induction of the Arabidopsis XERO2 dehydrin gene by abscisic acid and coldTHE PLANT JOURNAL, Issue 1 2008Susanna Chung Summary Multiple combinations of mutations in the promoter of the XERO2 dehydrin gene were used to identify elements involved in ABA and cold induction. Mutating one of the three ACGT elements (ACGT1) increases expression in the absence of cold or ABA. An AT-rich element is a novel partner (coupling element) of ACGT-containing ABA-responsive cis -elements. A 12-bp palindrome also acts as a coupling element for ABA induction and includes one of the three dehydration-responsive element/C-repeat (DRE/CRT) elements and two overlapping motifs (TGTCG and TCGGC) previously shown to be statistically enriched in ABA-dependent and ,VP1 or ABA'-dependent activated genes (Plant Physiol. 2005; 139:437). At least two of the DRE/CRT elements are required for significant cold induction. During cold induction the AT-rich element also functions as a coupling element and ACGT1 is involved in repressing this induction. Two of the ACGT and DRE/CRT elements overlap, and mutating a single base in the ACGT of either of the two GCCGACGT sequences while retaining a DRE element reduced both ABA and cold induction. Changing the spatial relationships between the elements by deletion, inversion or insertion of DNA sequences reduced both cold and ABA induction. Overexpression of CBF1, ,2 or ,3 induced XERO2 expression in untreated plants. The ABI5 transcription factor may have a role in ABA-induced XERO2 expression, whereas ABI3 and ABI4 do not. The GCA2 gene was essential for both cold and ABA induction. A combination of the same overlapping and shared elements is used in the regulation of transcription by ABA and cold. [source] Abscisic acid and late embryogenesis abundant protein profile changes in winter wheat under progressive drought stressPLANT BIOLOGY, Issue 5 2010I. I. Vaseva Abstract Three varieties (cv. Pobeda, Katya and Sadovo) of winter wheat (Triticum aestivum), differing in their agronomic characteristics, were analysed during progressive soil water stress and recovery at early vegetation stages. Changes in abscisic acid content, SDS,PAGE and immunoblot profiles of proteins that remained soluble upon heating were monitored. Initially higher ABA content in control Pobeda and Katya corresponded to earlier expression of the studied late embryogenesis abundant (LEA) proteins. A combination of higher ABA content, early immunodetection of dehydrins, and a significant increase of WZY2 transcript levels were observed in drought-stressed leaves of the tolerant variety Katya. One-step RT-PCR analyses of some acidic dehydrin genes (WCOR410b, TADHN) documented their relatively constant high expression levels in leaves under drought stress during early vegetative development. Neutral WZY2 dehydrin, TaLEA2 and TaLEA3 transcripts accumulated gradually with increasing water deficit. Delayed expression of TaLEA2 and TaLEA3 genes was found in the least drought-tolerant wheat, Sadovo. The expression profile of WZY2 revealed two distinct and separate bands, suggesting alternative splicing, which altered as water stress increased. [source] Identification of barley mutants in the cultivar ,Lux' at the Dhn loci through TILLINGPLANT BREEDING, Issue 4 2009S. Lababidi Abstract TILLING is a reverse genetic strategy that allows screening for mutations in genes with known sequences in a plant mutant population. A TILLING population has been developed for the Danish barley variety ,Lux' (Hordeum vulgare L.), by using sodium azide to induce mutations. Scoring of four visible phenotypic characters of barley seedling in reference to the parental cultivar ,Lux' in the M3 plants showed over 3.5% lethality. A series of pool ratios of mixed DNA from mutant lines were tested and 10-fold pools appeared to be the practical mixing ratio for the detection of fragments in the 500,700 bp range. Two of the 13 known dehydrin genes, Dhn12 and Dhn13, respectively, were examined and five independent missense mutations were obtained from a population of 9575 barley mutant plants. This corresponds to a mutation density of approximately one mutation every two and half million base pairs for these two genes. The mutant population of approximately 10 000 lines was screened for mutations in two genes in a short time due to high pooling ratio. [source] | ||||||||||