• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.238-244
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• 2003

During the life cycle, plants have to suffer from various environmental stresses. A common element in response to many environmental stresses is cellular dehydration. Dehydrins are a family of proteins commonly induced by environmental stresses associated with low temperature or dehydration and during seed maturation drying. For the study in the defense mechanism against various stresses, a cDNA clone encoding a dehydrin gene was isolated from a cDNA library prepared from tab root mRNAs of Codonopsis lanceolata. The cDNA, designated ClDhn1, is 893 nucleotides long and has an open reading frame of 480 bp with a deduced amino acid sequence of 159 residues. The ClDhn1 amino acid sequence is highly hydrophilic and possesses two conserved repeats of characterized lysine­rich K­segment (KIKEKLPG), and a 7­serine residue stretch prior to the first lysine­rich repeat that is common to many dehydrins. The DEYGNP conserved motif is, however, modified in the sequence of ClDhn1 gene. The deduced amino acid sequence of ClDhn1 was compared with other plant dehydrinls and showed high homology with Solanum commersonii

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.116-122
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• 2002

Dehydrins (LEA Dll proteins) are one of the typical families of plant proteins that accumulate in response to dehydration, cold stress, abscisic acid, or during seed maturation. A 1.3-kb cDNA was cloned from a cDNA expression library of 5-day-old germinating maize scutellums under drought stress. The deduced protein sequence indicated a dehydrin gene encoding SK$_3$ LEA protein typically expressed during cold acclimation, but not by drought stress in barley and wheat. Thus, it was named maize DEHYDRIN2 (ZmDhn2). It accumulates rapidly and highly in drought-stressed scutellum and leaf tissues at any stage, but not under cold stress. ZmDhn2 gene was transformed into Arabidopsis thaliana for functional analysis under drought condition. From electrolyte leakage test, no significant difference showed between wild type and transformants under normal growth condition, but the leakage level of electrolyte in wild type plants was about 3 times as high as that in the transformed plants under drought stress. It suggests that ZmDHN2 playa role in increasing drought tolerance.

• Molecules and Cells
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• v.19 no.2
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• pp.212-218
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• 2005

A full-length 1.1 kb cDNA, designated Oryza sativa Dehydrin 1 (OsDhn1), was isolated from the seed coat of rice. The deduced protein is hydrophilic and has three K-type and one S-type motifs (SK3-type), indicating that OsDhn1 belongs to the acidic dehydrin family, which includes wheat WCOR410 and Arabidopsis COR47. Expression of OsDhn1 was strongly induced by low temperature as well as by drought. Induction of OsDhn1 by cold stress was clearcut in the roots of seedlings and the epidermis of palea and lemma. OsDhn1 was also up-regulated in UBI::CBF1/DREB1b transgenic plants indicating that it is regulated by the CBF/DREB stress signaling pathway.

• BMB Reports
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• v.41 no.4
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• pp.338-343
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• 2008

Dehydrins (DHNs) compose a family of intrinsically unstructured proteins that have high water solubility and accumulate during late seed development at low temperature or in water-deficit conditions. They are believed to play a protective role in freezing and drought-tolerance in plants. A full-length cDNA encoding DHN (designated as ClDhn) was isolated from an oriental medicinal plant Codonopsis lanceolata, which has been used widely in Asia for its anticancer and anti-inflammatory properties. The full-length cDNA of ClDhn was 813 bp and contained a 477 bp open reading frame (ORF) encoding a polypeptide of 159 amino acids. Deduced ClDhn protein had high similarities with other plant DHNs. RT-PCR analysis showed that different abiotic stresses such as salt, wounding, chilling and light, triggered a significant induction of ClDhn at different time points within 4-48 hrs post-treatment. This study revealed that ClDhn assisted C. lanceolata in becoming resistant to dehydration.

• Journal of Plant Biotechnology
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• v.38 no.3
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• pp.203-208
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• 2011

We transferred Dhn5 (dehydrin5) gene from barley to poplar to determine the effect of its expression on the transgenic poplars. The results from northern blot analysis showed that the expression level of gene varied among the transgenic lines. During their culture on tissue culture media, the transgenic poplars formed vigorous growing callus in the presence of 5% PEG. When the transgenic poplars were growing in pots and witheld watering, they stayed much healthier than nontransgenic poplars. The transgenic poplars showed higher rates of photosynthetic rates, stomatal conductance and evaporation rates under the drought stress, although there was no significant difference in soil water content within the treatments. The relative electrical conductivity of the transgenic poplars after 20% PEG treatment was lower than that of nontransgenic poplars. The results provide evidence that the expression of hvDhn5 gene conferred drought tolerance in the transgenic poplars.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.315-321
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• 2003

Freezing and drought tolerances in plants are very important for survival in the desert. In an effort to reduce desertifcation in Gobi, a molecular breeding of Artemisia adamsii using the CLP (chitinase like protein, antifreeze protein) and Dhn5 (dehydrin5) genes from barley is performed by introducing them into Artemisia adamsii via Agrobacteria. We had found an optimal combinatorial concentration of hormones at 0.05mg/L of NAA and 0.5mg/L of BA for growth of callus in Artemisia adamsii. In addition, the higher rate of callus induction using hypocotyl as explant was observed comparing to explants of stem and leaf. There were some variations in the level of the proteins expressed among the transgenic lines such that the lines of CLP(CS1-5, 1-7,4-4) and Dhn5(DS2-2, 2-3) lines produce the protein to higher levels. The transgenic lines showing a higher level of Dhn5 exhibited better growth than nontransgenic callus in presence of 10 and 20％ PEG. In case of the CLP tansgenic lines, both CS1-5 and CS1-7 showed a higher level of freezing tolerance determined by ion leakage test.