Natural Academy of Agricultural Science

Suigen, South Korea

Natural Academy of Agricultural Science

Suigen, South Korea
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Kim S.,Konkuk University | Lee S.-B.,Konkuk University | Han C.-S.,Konkuk University | Lim M.-N.,Konkuk University | And 3 more authors.
Journal of Plant Physiology | Year: 2017

Oleosins are the most abundant proteins in the monolipid layer surrounding neutral storage lipids that form oil bodies in plants. Several lines of evidence indicate that they are physiologically important for the maintenance of oil body structure and for mobilization of the lipids stored inside. Rice has six oleosin genes in its genome, the expression of all of which was found to be responsive to abscisic acid (ABA) in our examination of mature embryo and aleurone tissues. The 5′-flanking region of OsOle5 was initially characterized for its responsiveness to ABA through a transient expression assay system using the protoplasts from suspension-cultured rice cells. A series of successive deletions and site-directed mutations identified five regions critical for the hormonal induction of its promoter activity. A search for cis-acting elements in these regions deposited in a public database revealed that they contain various promoter elements previously reported to be involved in the ABA response of various genes. A gain-of-function experiment indicated that multiple copies of all five regions were sufficient to provide the minimal promoter with a distinct ABA responsiveness. Comparative sequence analysis of the short, but still ABA-responsive, promoters of OsOle genes revealed no common modular architecture shared by them, indicating that various distinct promoter elements and independent trans-acting factors are involved in the ABA responsiveness of rice oleosin multigenes. © 2017 Elsevier GmbH


Lee J.,Gwangju Institute of Science and Technology | Lee D.,Gwangju Institute of Science and Technology | Choi H.,Kyungpook National University | Kim H.H.,Chung - Ang University | And 4 more authors.
Biochemical and Biophysical Research Communications | Year: 2014

Coprisin is a 43-mer defensin-like peptide from the dung beetle, Copris tripartitus. CopA3 (LLCIALRKK-NH2), a 9-mer peptide containing a single free cysteine residue at position 3 of its sequence, was derived from the α-helical region of coprisin and exhibits potent antibacterial and anti-inflammatory activities. The single cysteine implies a tendency for dimerization; however, it remains unknown whether this cysteine residue is indispensible for CopA3's antimicrobial activity. To address this issue, in the present study we synthesized eight cysteine-substituted monomeric CopA3 analogs and two dimeric analogs, CopA3 (Dimer) and CopIK (Dimer), and evaluated their antimicrobial effects against bacteria and fungi, as well as their hemolytic activity toward human erythrocytes. Under physiological conditions, CopA3 (Mono) exhibits a 6/4 (monomer/dimer) molar ratio in HPLC area percent, indicating that its effects on bacterial strains likely reflect a CopA3 (Mono)/CopA3 (Dimer) mixture. We also report the identification of CopW, a new cysteine-free nonapeptide derived from CopA3 that has potent antimicrobial activity with virtually no hemolytic activity. Apparently, the cysteine residue in CopA3 is not essential for its antimicrobial function. Notably, CopW also exhibited significant synergistic activity with ampicillin and showed more potent antifungal activity than either wild-type coprisin or melittin. © 2013 Elsevier Inc. All rights reserved.


Lee J.,Gwangju Institute of Science and Technology | Lee D.,Gwangju Institute of Science and Technology | Choi H.,Kyungpook National University | Kim H.H.,Chung - Ang University | And 4 more authors.
BMB Reports | Year: 2014

Defensins, which are small cationic molecules produced by organisms as part of their innate immune response, share a common structural scaffold that is stabilized by three disulfide bridges. Coprisin is a 43-amino acid defensin-like peptide from Copris tripartitus. Here, we report the intramolecular disulfide connectivity of cysteine-rich coprisin, and show that it is the same as in other insect defensins. The disulfide bond pairings of coprisin were determined by combining the enzymatic cleavage and mass analysis. We found that the loss of any single disulfide bond in coprisin eliminated all antibacterial, but not antifungal, activity. Circular dichroism (CD) analysis showed that two disulfide bonds, Cys20-Cys39 and Cys24- Cys41, stabilize coprisin's a-helical region. Moreover, a BLAST search against UniProtKB database revealed that coprisin's a-helical region is highly homologous to those of other insect defensins. © 2014 by the The Korean Society for Biochemistry and Molecular Biology.


PubMed | Natural Academy of Agricultural Science, Kyungpook National University, Gwangju Institute of Science and Technology, Chung - Ang University and Daejin University
Type: Journal Article | Journal: BMB reports | Year: 2014

Defensins, which are small cationic molecules produced by organisms as part of their innate immune response, share a common structural scaffold that is stabilized by three disulfide bridges. Coprisin is a 43-amino acid defensin-like peptide from Copris tripartitus. Here, we report the intramolecular disulfide connectivity of cysteine-rich coprisin, and show that it is the same as in other insect defensins. The disulfide bond pairings of coprisin were determined by combining the enzymatic cleavage and mass analysis. We found that the loss of any single disulfide bond in coprisin eliminated all antibacterial, but not antifungal, activity. Circular dichroism (CD) analysis showed that two disulfide bonds, Cys20-Cys39 and Cys24-Cys41, stabilize coprisins -helical region. Moreover, a BLAST search against UniProtKB database revealed that coprisins -helical region is highly homologous to those of other insect defensins.


PubMed | Natural Academy of Agricultural Science, Kyungpook National University, Gwangju Institute of Science and Technology, Chung - Ang University and Daejin University
Type: Journal Article | Journal: Biochemical and biophysical research communications | Year: 2014

Coprisin is a 43-mer defensin-like peptide from the dung beetle, Copris tripartitus. CopA3 (LLCIALRKK-NH), a 9-mer peptide containing a single free cysteine residue at position 3 of its sequence, was derived from the -helical region of coprisin and exhibits potent antibacterial and anti-inflammatory activities. The single cysteine implies a tendency for dimerization; however, it remains unknown whether this cysteine residue is indispensible for CopA3s antimicrobial activity. To address this issue, in the present study we synthesized eight cysteine-substituted monomeric CopA3 analogs and two dimeric analogs, CopA3 (Dimer) and CopIK (Dimer), and evaluated their antimicrobial effects against bacteria and fungi, as well as their hemolytic activity toward human erythrocytes. Under physiological conditions, CopA3 (Mono) exhibits a 6/4 (monomer/dimer) molar ratio in HPLC area percent, indicating that its effects on bacterial strains likely reflect a CopA3 (Mono)/CopA3 (Dimer) mixture. We also report the identification of CopW, a new cysteine-free nonapeptide derived from CopA3 that has potent antimicrobial activity with virtually no hemolytic activity. Apparently, the cysteine residue in CopA3 is not essential for its antimicrobial function. Notably, CopW also exhibited significant synergistic activity with ampicillin and showed more potent antifungal activity than either wild-type coprisin or melittin.


Um S.,Seoul National University | Bang H.-S.,Natural Academy of Agricultural Science | Shin J.,Seoul National University | Oh D.-C.,Seoul National University
Natural Product Sciences | Year: 2013

Actinofuranone C (1), a new 3-furanone-bearing polyketide, was isolated from an actinobacterium (Amycolatopsis sp.) associated with a female of the dung beetle, Copris tripartitus Waterhouse. The structure of actinofuranone C was elucidated by the spectroscopic interpretation of NMR, mass, UV, and IR data. The discovery of actinofuranone C indicates that chemical investigation of insect-associated microorganisms would be an effective strategy to explore natural chemical diversity.


Lee S.-E.,Konkuk University | Yim H.-K.,Konkuk University | Lim M.-N.,Konkuk University | Yoon I.S.,Natural Academy of Agricultural Science | And 2 more authors.
Journal of Experimental Botany | Year: 2015

Tonoplast intrinsic proteins (TIPs) are integral membrane proteins that are known to function in plants as aquaporins. Here, we propose another role for TIPs during the fusion of protein storage vacuoles (PSVs) in aleurone cells, a process that is promoted by gibberellic acid (GA) and prevented by abscisic acid (ABA). Studies of the expression of barley (Hordeum vulgare) TIP genes (HvTIP) showed that GA specifically decreased the abundance of HvTIP1;2 and HvTIP3;1 transcripts, while ABA strongly increased expression of HvTIP3;1. Increased or decreased expression of HvTIP3;1 interfered with the hormonal effects on vacuolation in aleurone protoplasts. HvTIP3;1 gain-of-function experiments delayed GA-induced vacuolation, whereas HvTIP3;1 loss-of-function experiments promoted vacuolation in ABA-treated aleurone cells. These results indicate that TIP plays a key role in preventing the coalescence of small PSVs in aleurone cells. Hormonal regulation of the HvTIP3;1 promoter is similar to the regulation of the endogenous gene, indicating that induction of the transcription of HvTIP3;1 by ABA is a critical factor in the prevention of PSV coalescence in response to ABA. Promoter analysis using deletions and site-directed mutagenesis of sequences identified three cis-acting elements that are responsible for ABA responsiveness in the HvTIP3;1 promoter. Promoter analysis also showed that ABA responsiveness of the HvTIP3;1 promoter is likely to occur via a unique regulatory system distinct from that involving the ABA-response promoter complexes. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved.


Lim M.-N.,Konkuk University | Lee S.-E.,Konkuk University | Yim H.-K.,Konkuk University | Kim J.H.,Daegu University | And 2 more authors.
Molecules and Cells | Year: 2013

The interaction between the dual roles of sugar as a metabolic fuel and a regulatory molecule was unveiled by examining the changes in sugar signaling upon oxygen deprivation, which causes the drastic alteration in the cellular energy status. In our study, the expression of anaerobically induced genes is commonly responsive to sugar, either under the control of hexokinase or non-hexokinase mediated signaling cascades. Only sugar regulation via the hexokinase pathway was susceptible for O2 deficiency or energy deficit conditions evoked by uncoupler. Examination of sugar regulation of those genes under anaerobic conditions revealed the presence of multiple paths underlying anaerobic induction of gene expression in rice, subgrouped into three distinct types. The first of these, which was found in type-1 genes, involved neither sugar regulation nor additional anaerobic induction under anoxia, indicating that anoxic induction is a simple result from the release of sugar repression by O2-deficient conditions. In contrast, type-2 genes also showed no sugar regulation, albeit with enhanced expression under anoxia. Lastly, expression of type-3 genes is highly enhanced with sugar regulation sustained under anoxia. Intriguingly, the inhibition of the mitochondrial ATP synthesis can reproduce expression pattern of a specific set of anaerobically induced genes, implying that rice cells may sense O2 deprivation, partly via perception of the perturbed cellular energy status. Our study of interaction between sugar signaling and anaerobic conditions has revealed that sugar signaling and the cellular energy status are likely to communicate with each other and influence anaerobic induction of gene expression in rice.

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