• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.51 no.1
• /
• pp.66-72
• /
• 2006

Spikelet proteins expressed at the young microspore stage in rice were separated and analysed by two-dimensional polyacrylamide gel electrophoresis (2DE). The separated proteins were electro blotted onto a polyvinylidene difluoride (PVDF) membrane, and 50 proteins were analyzed by a gas-phase protein sequencer. The N-terminal amino acid sequences of 20 out of 50 proteins were determined. N-terminal regions of the remaining proteins could not be sequenced because of blocking. The internal amino acid sequences of proteins were determined by sequence analysis of peptides obtained by the Cleveland peptide mapping method. Results revealed the presence of the photosynthetic apparatus at rice young microspore stage. Major proteins identified in this study could be used as a marker for various studies on physiological stresses.

• Journal of Microbiology
• /
• v.41 no.4
• /
• pp.340-344
• /
• 2003

The group I intron from Tetrahymena thermophila has been demonstrated to employ splicing reactions with its substrate RNA in the trans configuration. Moreover, we have recently shown that the transsplicing group I ribozyme can replace HCV-specific transcripts with a new RNA that exerts anti-viral activity. In this study, we explored the potential use of RNA replacement for cancer treatment by developing trans-splicing group I ribozymes, which could replace tumor-associated RNAs with the RNA sequence attached to the 3' end of the ribozymes. Thymidine phosphorylase (TP) RNA was chosen as a target RNA because it is known as a valid cancer prognostic factor. By performing an RNA mapping strategy that is based on a trans-splicing ribozyme library, we first determined which regions of the TP RNA are accessible to ribozymes, and found that the leader sequences upstream of the AUG start codon appeared to be particularly accessible. Next, we assessed the ribozyme activities by comparing trans-splicing activities of several ribozymes that targeted different regions of the TP RNA. This assessment was performed to verify if the target site predicted to be accessible is truly the most accessible. The ribozyme that could target the most accessible site, identified by mapping studies, was the most active with high fidelity in vitro. Moreover, the specific trans-splicing ribozyme reacted with and altered the TP transcripts by transferring an intended 3' exon tag sequence onto the targeted TP RNA in mammalian cells with high fidelity. These results suggest that the Tetrahymena ribozyme can be utilized to replace TP RNAs in tumors with a new RNA harboring anti-cancer activity, which would revert the malignant phenotype.

• Journal of Convergence for Information Technology
• /
• v.11 no.2
• /
• pp.25-30
• /
• 2021

In this paper, we studied the coding technique for flicker mitigation and BER performance improvement in visible light communication system. In order to increase the transmission speed of visible light communication, a multi-transmission multi-LED transmission system using a plurality of LEDs is being actively studied. However, when data is transmitted through N LEDs in a multi-LED visible light communication system using N LEDs, there is a continuous zero section in which 0 is transmitted simultaneously according to the data sequence, and since the transmission section of 1 is different, flickering Or, a phenomenon in which the dimming level changes occurs. The visible light communication system is a communication system that simultaneously performs communication and lighting functions. Therefore, transmission efficiency of communication and brightness of lighting must be considered at the same time. To solve this problem, we proposed a flicker reduction mapping that can alleviate flicker and dimming level problems, improve error detection and BER performance through coding mapping of each LED data sequence.

• Investigative Magnetic Resonance Imaging
• /
• v.23 no.4
• /
• pp.328-340
• /
• 2019

Purpose: To generate phase images with free of motion-induced artifact and susceptibility-induced distortion using 3D radial ultrashort TE (UTE) MRI. Materials and Methods: The field map was theoretically derived by solving Laplace's equation with appropriate boundary conditions, and used to simulate the image distortion in conventional spin-warp MRI. Manufacturer's 3D radial imaging sequence was modified to acquire maximum number of radial spokes in a given time, by removing the spoiler gradient and sampling during both rampup and rampdown gradient. Spoke direction randomly jumps so that a readout gradient acts as a spoiling gradient for the previous spoke. The custom raw data was reconstructed using a homemade image reconstruction software, which is programmed using Python language. The method was applied to a phantom and in-vivo human brain and abdomen. The performance of UTE was compared with 3D GRE for phase mapping. Local phase mapping was compared with T₂* mapping using UTE. Results: The phase map using UTE mimics true field-map, which was theoretically calculated, while that using 3D GRE revealed both motion-induced artifact and geometric distortion. Motion-free imaging is particularly crucial for application of phase mapping for abdomen MRI, which typically requires multiple breathold acquisitions. The air pockets, which are caught within the digestive pathway, induce spatially varying and large background field. T₂* map, that was calculated using UTE data, suffers from non-uniform T₂* value due to this background field, while does not appear in the local phase map of UTE data. Conclusion: Phase map generated using UTE mimicked the true field map even when non-zero susceptibility objects were present. Phase map generated by 3D GRE did not accurately mimic the true field map when non-zero susceptibility objects were present due to the significant field distortion as theoretically calculated. Nonetheless, UTE allows for phase maps to be free of susceptibility-induced distortion without the use of any post-processing protocols.

• Journal of Plant Biotechnology
• /
• v.35 no.4
• /
• pp.265-274
• /
• 2008

Glutathione S-transferases (GSTs) are multifunctional proteins encoded by a large gene family divided into Phi, Tau, Theta, Zeta, Lambda and DHAR classes on the basis of sequence identity. The Phi(F) and Tau(U) classes are plant-specific and ubiquitous. Their roles have been defined as herbicide detoxification and responses to biotic and abiotic stresses. Fifty-two members of the GST super-family were identified in the Arabidopsis thaliana genome, 13 members of which belong to the Phi class of GSTs (AtGSTFs). Based on the sequence similarities of AtGSTFs, 11 BAC clones were identified from Brassica rapa. Seven unique sequences of ORFs designated the Phi class candidates of GST derived from B. rapa (BrGSTFs) were detected from these 11 BAC clones by blast search and sequence alignment. Some of BrGSTFs were present in the same BAC clones indicating that BrGSTFs could also be clustered as usual in plant. They were mapped on B. rapa linkage group 2, 3, 9 and 10 and their nucleotide and amino acid sequences were highly similar to those of AtGSTFs. In addition, in silico analysis of BrGSTFs using Korea Brassica Genome Project 24K oligochip and microarray database for cold, salt and drought stresses revealed 15 unigenes to be highly similar to AtGSTFs and six of these were identical to one of BrGSTFs identified in the BAC clones indicating their expression. The sequences of BrGSTFs and unigenes identified in this study will facilitate further studies to apply GST genes to medical and agriculture purposes.

• The Plant Pathology Journal
• /
• v.18 no.2
• /
• pp.85-92
• /
• 2002

A new isolate of Cucumber mosaic virus (CMV), identified as Li-CMV was isolated from a diseased Korean native lily (Lithium tsingtauense Gilg). Biological and serological properties of Li-CMV were characterized, and reverse transcription-polymerase chain reaction (RT-PCR) analysis, restriction enzyme profiling of RT-PCR products, and nucleotide sequence analysis of RNA3 of the virus were performed in this study. Remarkable differences in symptoms between Li-CMV and ordinary CMV strains were found in tobacco plants and Datura stramonium. Li-CMV-infected tobacco plants (cv. Xanthi-nc and cv. Samsun) induced chlorotic ringspots on uninoculated upper leaves, and the symptom expression was delayed or faint whereas, ordinary CMV strains induced green mosaic symptoms on the plant. Systemic infections were observed on Nicotiana benthamiana with severe mosaic symptom. Restriction mapping analysis of RT-PCR products using MspI showed that Li-CMV belonged to CMV subgroup I. A full-length CDNA copy of RNA3 for the virus was amplified by RT-PCR, cloned, and its complete nucleotide sequence was determined. The RNA3 of Li-CMV was 2, 232 nucleotides long, and consisted of two open reading frames of 843 and 657 bases encoding 3a protein (movement protein) and coat protein, respectively. Results of this study indicate that Li-CMV is a novel strain and belongs to subgroup I of CMV in the genus Cucumovirus.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.4A
• /
• pp.288-295
• /
• 2005

OFDM communications system is very attractive for the high data rate wireless transmission. However, it may be distorted in the nonlinear HPA since OFDM signal has high PAPR. So, a new SLM method using dummy sequence is studied for reducing the PAPR, and we call it DSI-SLM method. Unlike the conventional SLM method using the phase rotation, dummy sequences for PAPR reduction are assigned at the predefined sub-carriers. After IFFT, the OFDM data signal of the lowest PAPR is selected to transmit. So, it can cut down the computational complexity because it does not require the transmission and demodulation process of side information about the phase rotation. This proposed method can solve the time delay problem so that PAPR reduction can be made in real time processing.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.11
• /
• pp.4005-4010
• /
• 2011

We investigated thermal behavior of spin-coated films of P(HB-co-HHx)/PEG blends by using infraredreflection absorption (IRRAS) spectroscopy and 2D correlation spectroscopy. Based on 2D IRRAS correlation spectra, we could determine the sequence of spectral intensity changes with increasing temperature that PEG band changes first and then a band for crystalline component of P(HB-co-HHx) changes before a band for amorphous component. The intensities of bands for PEG and amorphous P(HB-co-HHx) were changed greatly as PEG weigh % of P(HB-co-HHx)/PEG blends increased. Transition temperatures of P(HB-co-HHx)/PEG blends were successfully determined by 2D gradient mapping method. The transition temperature of spincoated films of 98/2 and 90/10 P(HB-co-HHx)/PEG blends and 80/20 P(HB-co-HHx)/PEG blend determined by 2D gradient map are, respectively, about 137.5 and $132.5^{\circ}C$. Furthermore, P(HB-co-HHx)/PEG blends show an additional transition temperature that have been interpreted in terms of different lamellar thicknesses in spin coated films.

• Horticultural Science & Technology
• /
• v.35 no.2
• /
• pp.149-164
• /
• 2017

Next generation sequencing (NGS) technologies have led to the rapid accumulation of genome sequences through whole-genome sequencing and re-sequencing of crop species. Genomic resources provide the opportunity for a new revolution in plant breeding by facilitating the dissection of complex traits. Among vegetable crops, reference genomes have been sequenced and assembled for several species in the Solanaceae and Cucurbitaceae families, including tomato, pepper, cucumber, watermelon, and melon. These reference genomes have been leveraged for re-sequencing of diverse germplasm collections to explore genome-wide sequence variations, especially single nucleotide polymorphisms (SNPs). The use of genome-wide SNPs and high-throughput genotyping methods has led to the development of new strategies for dissecting complex quantitative traits, such as genome-wide association study (GWAS). In addition, the use of multi-parent populations, including nested association mapping (NAM) and multiparent advanced generation intercross (MAGIC) populations, has helped increase the accuracy of quantitative trait loci (QTL) detection. Consequently, a number of QTL have been discovered for agronomically important traits, such as disease resistance and fruit traits, with high mapping resolution. The molecular markers for these QTL represent a useful resource for enhancing selection efficiency via marker-assisted selection (MAS) in vegetable breeding programs. In this review, we discuss current genomic resources and marker-trait association analysis to facilitate genome-assisted breeding in vegetable species in the Solanaceae and Cucurbitaceae families.

• Molecules and Cells
• /
• v.39 no.6
• /
• pp.460-467
• /
• 2016

Bacteriophytochromes are phytochrome-like light-sensing photoreceptors that use biliverdin as a chromophore. To study the biochemical properties of the Deinococcus radiodurans bacteriophytochrome (DrBphP) protein, two anti-DrBphP mouse monoclonal antibodies (2B8 and 3H7) were generated. Their specific epitopes were identified in our previous report. We present here fine epitope mapping of these two antibodies by using truncation and substitution of original epitope sequences in order to identify minimized epitope peptides. The previously reported original epitope sequences for 2B8 and 3H7 were truncated from both sides. Our analysis showed that the minimal peptide sequence lengths for 2B8 and 3H7 antibodies were nine amino acids (RDPLPFFPP) and six amino acids (PGEIEE), respectively. We further characterized these peptides in order to investigate their reactivity after single deletion and single substitution of the original peptides. We found that single-substituted 2B8 epitope (RDPLPAFPP) and dual-substituted 3H7 epitope (PGEIAD) showed significantly increased reactivity. These two antibodies with high reactivity for the short modified peptide sequences are valueble for developing new peptide tags for protein research.