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1.  Fruit Indehiscence Caused by Enhanced Expression of NO TRANSMITTING TRACT in Arabidopsis thaliana 
Molecules and Cells  2013;35(6):519-525.
In flowering plants, fruit dehiscence enables seed dispersal. Here we report that ntt-3D, an activation tagged allele of NO TRANSMITTING TRACT (NTT), caused a failure of fruit dehiscence in Arabidopsis. We identified ntt-3D, in which the 35S enhancer was inserted adjacent to AT3G- 57670, from our activation tagged mutant library. ntt-3D mutants showed serrated leaves, short siliques, and indehiscence phenotypes. NTT-overexpressing plants largely phenocopied the ntt-3D plants. As the proximate cause of the indehiscence, ntt-3D plants exhibited a near absence of valve margin and lignified endocarp b layer in the carpel. In addition, the replum was enlarged in ntt-3D mutants. NTT expression reached a peak in flowers at stage 11 and gradually decreased thereafter and pNTT::GUS expression was mainly observed in the replum, indicating a potential role in fruit patterning. NTT:GFP localized in the nucleus and cytoplasm. FRUITFULL (FUL) expression was downregulated in ntt-3D mutants and ntt-3D suppressed upregulation of FUL in replumless mutants. These results indicate that NTT suppresses FUL, indicating a potential role in patterning of the silique. In seed crops, a reduction in pod dehiscence can increase yield by decreasing seed dispersal; therefore, our results may prove useful as a basis to improve crop yield.
PMCID: PMC3887870  PMID: 23515580
carpel development; dehiscent zone; endocarp b layer; fruit indehiscence; replum
2.  Formation of perfect ohmic contact at indium tin oxide/N,N′-di(naphthalene-1-yl)-N,N′-diphenyl-benzidine interface using ReO3 
Scientific Reports  2014;4:3902.
A perfect ohmic contact is formed at the interface of indium tin oxide (ITO) and N,N′-di(naphthalene-1-yl)-N,N′-diphenyl-benzidine (NPB) using ReO3 as the interfacial layer. The hole injection efficiency is close to 100% at the interface, which is much higher than those for interfacial layers of 1,4,5,8,9,11-hexaazatripheylene hexacarbonitrile (HAT-CN) and MoO3. Interestingly, the ReO3 and MoO3 interfacial layers result in the same hole injection barrier, ≈0.4 eV, to NPB, indicating that the Fermi level is pinned to the NPB polaron energy level. However, a significant difference is observed in the generated charge density in the NPB layer near the interfacial layer/NPB interface, indicating that charge generation at the interface plays an important role in forming the ohmic contact.
PMCID: PMC3904154  PMID: 24469505
3.  Intracellular Reprogramming of Expression, Glycosylation, and Function of a Plant-Derived Antiviral Therapeutic Monoclonal Antibody 
PLoS ONE  2013;8(8):e68772.
Plant genetic engineering, which has led to the production of plant-derived monoclonal antibodies (mAbPs), provides a safe and economically effective alternative to conventional antibody expression methods. In this study, the expression levels and biological properties of the anti-rabies virus mAbP SO57 with or without an endoplasmic reticulum (ER)-retention peptide signal (Lys-Asp-Glu-Leu; KDEL) in transgenic tobacco plants (Nicotiana tabacum) were analyzed. The expression levels of mAbP SO57 with KDEL (mAbPK) were significantly higher than those of mAbP SO57 without KDEL (mAbP) regardless of the transcription level. The Fc domains of both purified mAbP and mAbPK and hybridoma-derived mAb (mAbH) had similar levels of binding activity to the FcγRI receptor (CD64). The mAbPK had glycan profiles of both oligomannose (OM) type (91.7%) and Golgi type (8.3%), whereas the mAbP had mainly Golgi type glycans (96.8%) similar to those seen with mAbH. Confocal analysis showed that the mAbPK was co-localized to ER-tracker signal and cellular areas surrounding the nucleus indicating accumulation of the mAbP with KDEL in the ER. Both mAbP and mAbPK disappeared with similar trends to mAbH in BALB/c mice. In addition, mAbPK was as effective as mAbH at neutralizing the activity of the rabies virus CVS-11. These results suggest that the ER localization of the recombinant mAbP by KDEL reprograms OM glycosylation and enhances the production of the functional antivirus therapeutic antibody in the plant.
PMCID: PMC3744537  PMID: 23967055
4.  Expression of GA733-Fc Fusion Protein as a Vaccine Candidate for Colorectal Cancer in Transgenic Plants 
The tumor-associated antigen GA733 is a cell-surface glycoprotein highly expressed in colorectal carcinomas. In this study, 3 recombinant genes were constructed as follows: GA733 tagged to the ER retention sequence KDEL (GA733K), GA733 fused to the immunoglobulin Fc fragment (GA733-Fc), and GA733-Fc fused to the ER retention sequence (GA733-FcK). Agrobacterium-mediated transformation was used to generate transgenic plants expressing recombinant genes. The presence of transgenes was confirmed by genomic PCR. Western blot, confocal immunofluorescence, and sandwich ELISA showed the expression of recombinant proteins. The stability, flexibility, and bioactivity of recombinant proteins were analyzed and demonstrated through N-glycosylation analysis, animal trials, and sera ELISA. Our results suggest that the KDEL retained proteins in ER with oligomannose glycan structure and enhanced protein accumulation level. The sera of mice immunized with GA733-FcK purified from plants contained immunoglobulins which were at least as efficient as the mammalian-derived GA733-Fc at recognizing human colorectal cancer cell lines. Thus, a plant system can be used to express the KDEL fusion protein with oligomannose glycosylation, and this protein induces an immune response which is comparable to non-KDEL-tagged, mammalian-derived proteins.
PMCID: PMC3366255  PMID: 22675251
5.  High Dose Vitamin D3 Attenuates the Hypocalciuric Effect of Thiazide in Hypercalciuric Rats 
Journal of Korean Medical Science  2010;25(9):1305-1312.
Thiazide is known to decrease urinary calcium excretion. We hypothesized that thiazide shows different hypocalciuric effects depending on the stimuli causing hypercalciuria. The hypocalciuric effect of hydrochlorothiazide (HCTZ) and the expression of transient receptor potential vanilloid 5 (TRPV5), calbindin-D28K, and several sodium transporters were assessed in hypercalciuric rats induced by high calcium diet and vitamin D3. Urine calcium excretion and the expression of transporters were measured from 4 groups of Sprague-Dawley rats; control, HCTZ, high calcium-vitamin D, and high calcium-vitamin D with HCTZ groups. HCTZ decreased urinary calcium excretion by 51.4% in the HCTZ group and only 15% in the high calcium-vitamin D with HCTZ group. TRPV5 protein abundance was not changed by HCTZ in the high calcium-vitamin D with HCTZ group compared to the high calcium-vitamin D group. Protein abundance of NHE3, SGLT1, and NKCC2 decreased in the hypercalciuric rats, and only SGLT1 protein abundance was increased by HCTZ in the hypercalciuric rats. The hypocalciuric effect of HCTZ is attenuated in high calcium and vitamin D-induced hypercalciuric rats. This attenuation seems to have resulted from the lack of HCTZ's effect on protein abundance of TRPV5 in severe hypercalciuric condition induced by high calcium and vitamin D.
PMCID: PMC2923802  PMID: 20808673
Hypercalciuria; TRPV5; Sodium Transporters; Cholecalciferol; Thiazides
6.  Genetic framework for flowering-time regulation by ambient temperature-responsive miRNAs in Arabidopsis 
Nucleic Acids Research  2010;38(9):3081-3093.
Flowering is the primary trait affected by ambient temperature changes. Plant microRNAs (miRNAs) are small non-coding RNAs playing an important regulatory role in plant development. In this study, to elucidate the mechanism of flowering-time regulation by small RNAs, we identified six ambient temperature-responsive miRNAs (miR156, miR163, miR169, miR172, miR398 and miR399) in Arabidopsis via miRNA microarray and northern hybridization analyses. We also determined the expression profile of 120 unique miRNA loci in response to ambient temperature changes by miRNA northern hybridization analysis. The expression of the ambient temperature-responsive miRNAs and their target genes was largely anticorrelated at two different temperatures (16 and 23°C). Interestingly, a lesion in short vegetative phase (SVP), a key regulator within the thermosensory pathway, caused alteration in the expression of miR172 and a subset of its target genes, providing a link between a thermosensory pathway gene and miR172. The miR172-overexpressing plants showed a temperature-independent early flowering phenotype, suggesting that modulation of miR172 expression leads to temperature insensitivity. Taken together, our results suggest a genetic framework for flowering-time regulation by ambient temperature-responsive miRNAs under non-stress temperature conditions.
PMCID: PMC2875011  PMID: 20110261
7.  Structure-Based Design of Pteridine Reductase Inhibitors Targeting African Sleeping Sickness and the Leishmaniases† 
Journal of Medicinal Chemistry  2009;53(1):221-229.
Pteridine reductase (PTR1) is a target for drug development against Trypanosoma and Leishmania species, parasites that cause serious tropical diseases and for which therapies are inadequate. We adopted a structure-based approach to the design of novel PTR1 inhibitors based on three molecular scaffolds. A series of compounds, most newly synthesized, were identified as inhibitors with PTR1-species specific properties explained by structural differences between the T. brucei and L. major enzymes. The most potent inhibitors target T. brucei PTR1, and two compounds displayed antiparasite activity against the bloodstream form of the parasite. PTR1 contributes to antifolate drug resistance by providing a molecular bypass of dihydrofolate reductase (DHFR) inhibition. Therefore, combining PTR1 and DHFR inhibitors might improve therapeutic efficacy. We tested two new compounds with known DHFR inhibitors. A synergistic effect was observed for one particular combination highlighting the potential of such an approach for treatment of African sleeping sickness.
PMCID: PMC2804273  PMID: 19916554
8.  An Evaluation of Relative Damage to the Powertrain System in Tracked Vehicles 
Sensors (Basel, Switzerland)  2009;9(3):1845-1859.
The objective of this study was to improve the reliability of the endurance test for the powertrain system of military tracked vehicles. The measurement system that measures the driving duty applied to the powertrain system caused by mobility on roads consists of eight analog channels and two pulse channels, including the propeller shaft output torques for the left and right sides. The data obtained from this measurement system can be used to introduce a new technology that produces the output torque of a torque converter and that can be applied to analyze the revolution counting for the endurance and road mobility in the front unit and represent the relative fatigue damages analysis technique and its results according to the driven roads through a cumulative fatigue method.
PMCID: PMC3345845  PMID: 22573990
Relative damage; driving duty; revolution counting; fatigue life
9.  Effects of Thiazide on the Expression of TRPV5, Calbindin-D28K, and Sodium Transporters in Hypercalciuric Rats 
Journal of Korean Medical Science  2009;24(Suppl 1):S161-S169.
TRPV5 is believed to play an important role in the regulation of urinary calcium excretion. We assessed the effects of hydrochlorothiazide (HCTZ) on the expression of TRPV5, calbindin-D28K, and several sodium transporters in hypercalciuric rats. Sprague-Dawley rats were divided into 4 groups; control, HCTZ, high salt, and high salt with HCTZ group in experiment 1; control, HCTZ, high calcium (Ca), and high Ca with HCTZ group in experiment 2. To quantitate the expression of TRPV5, calbindin-D28K, and sodium transporters, western blotting was performed. In both experiments, HCTZ significantly decreased urinary calcium excretion. TRPV5 protein abundance decreased in all hypercalciuric rats, and restored by HCTZ in both high salt with HCTZ and high Ca with HCTZ group. Calbindin-D28K protein abundance increased in the high salt and high salt with HCTZ groups, but did not differ among groups in experiment 2. Protein abundance of NHE3 and NKCC2 decreased in all hypercalciuric rats, and were restored by HCTZ in only high Ca-induced hypercalciuric rats. In summary, protein abundance of TRPV5, NHE3, and NKCC2 decreased in all hypercalciuric rats. The hypocalciuric effect of HCTZ is associated with increased protein abundance of TRPV5 in high salt or calcium diet-induced hypercalciuric rats.
PMCID: PMC2633179  PMID: 19194547
Hypercalciuria; Thiazides; Transporters

Results 1-9 (9)