• Molecules and Cells
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• 제20권2호
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• pp.297-302
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• 2005

The integrity and proper functioning of telomeres require association of telomeric DNA sequences with specific binding proteins. We have characterized PLP-1, a $PUR{\alpha}$ homolog encoded by F45E4.2, which we previously identified as a candidate double stranded telomere binding protein, by affinity chromatography followed by mass spectrometry. PLP-1 bound double-stranded telomeric DNA in vitro as shown by competition assays. Core binding was provided by the third and fourth nucleotides of the TTAGGC telomeric repeat. This is quite different from the binding sequence of CEH-37, another C. elegans telomere binding protein, suggesting that multiple proteins may bind nematode telomeric DNA simultaneously in vivo.

• Genomics & Informatics
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• 제12권4호
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• pp.261-267
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• 2014

MicroRNAs (miRNAs) are known for their role in mRNA silencing via interference pathways. Repetitive elements (REs) share several characteristics with endogenous precursor miRNAs. In this study, 406 previously identified and 1,494 novel RE-derived miRNAs were sorted from the GENCODE v.19 database using the RepeatMasker program. They were divided into six major types, based on their genomic structure. More novel RE-derived miRNAs were confirmed than identified as RE-derived miRNAs. In conclusion, many miRNAs have not yet been identified, most of which are derived from REs.

• Horticulture, Environment, and Biotechnology : HEB
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• 제59권6호
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• pp.889-897
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• 2018

Currently, there is a lack of genetic markers capable of effectively detecting polymorphisms in Clematis. Therefore, we developed new markers to investigate inter- and intraspecific diversity in Clematis. Based on the complete chloroplast genome of Clematis terniflora, simple sequence repeats were explored and primer pairs were designed for all ten adequate repeat regions (cpSSRs), which were tested in 43 individuals of 11 Clematis species. In addition, the nuclear ITS region was sequenced in 11 Clematis species. Seven cpSSR loci were found to be polymorphic in the genus and serve as markers that can distinguish different species and be used in different genetic analyses, including cultivar identification to assist the breeding of new ornamental cultivars.

• 전자통신동향분석
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• 제34권6호
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• pp.87-99
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• 2019

Reinforcement learning is a type of machine learning paradigm that forces agents to repeat the observation-action-reward process to assess and predict the values of possible future action sequences. This allows the agents to incrementally reinforce the desired behavior for a given observation. Thanks to the recent advancements of deep learning, reinforcement learning has evolved into deep reinforcement learning that introduces promising results in various control and optimization domains, such as games, robotics, autonomous vehicles, computing, industrial control, and so on. In addition to this trend, a number of programming libraries have been developed for importing deep reinforcement learning into a variety of applications. In this article, we briefly review and summarize 10 representative deep reinforcement learning libraries and compare them from a development project perspective.

• 식물분류학회지
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• 제52권3호
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• pp.156-172
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• 2022

Campsis grandiflora (Thunb.) K. Schum is an ornamental species with various useful biological effects. The chloroplast genome of C. grandiflora isolated in Korea is 154,293 bp long (GC ratio: 38.1%) and has four subregions: 84,121 bp of large single-copy (36.2%) and 18,521 bp of small single-copy (30.0%) regions are separated by 24,332 bp of inverted repeat (42.9%) regions including 132 genes (87 protein-coding genes, eight rRNAs, and 37 tRNAs). One single-nucleotide polymorphism and five insertion and deletion (INDEL) regions (40-bp in total) were identified, indicating a low level of intraspecific variation in the chloroplast genome. All five INDEL regions were linked to the repetitive sequences. Seventy-two normal simple sequence repeats (SSRs) and 47 extended SSRs were identified to develop molecular markers. The phylogenetic trees of 29 representative Bignoniaceae chloroplast genomes indicate that the tribe-level phylogenic relationship is congruent with the findings of previous studies.

• 한국균학회지
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• 제42권1호
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• pp.50-56
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• 2014

본 연구에서는 큰느타리버섯 유전체내에 있는 retrotransposon의 탐색을 위하여 degenerated primer를 이용하여, retrotransposon library를 대장균에 제작하였다. 제작된 library에서 총 256개의 콜로니를 선택하여 염기서열을 결정한 결과, 71개가 LTR retrotransposon이며, 이들 중 70개가 Gypsy-type LTR retrotransposon임을 염기서열분석을 통하여 확인하였다. 특히 송이에서 발견된 MarY1_TM과 진황녹슨버짐버섯의 Gypsy-8_SLL이 각각 14, 18 copy 이상 큰느타리버섯 유전체에 삽입되어 있음을 Southern blot 분석을 통하여 밝혔다. 이와 더불어, 이들이 full length retrotransposon mRNA을 생산하고 있음을 RT-PCR과 northern blot을 통하여 밝힘으로서 활성이 있는 LTR retrotransposon임을 증명하였다.

• Reproductive and Developmental Biology
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• 제35권1호
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• pp.93-97
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• 2011

Previously, we reported that the osmolarity conditions in the satellite region were affected CpG DNA methylation status while Pre-1 sequence was not affected CpG DNA methylation in pNT blastocyst stage. This study was conducted to investigate the DNA methylation status of repeat sequences in pig nuclear transfer (pNT) embryos produced under different osmolarity culture conditions. Control group of pNT embryos was cultured in PZM-3 for six days. Other two treatment groups of pNT embryos were cultured in modified PZM-3 with 138 mM NaCl or 0.05 M sucrose (mPZM-3, 320 mOsmol) for two days, and then cultured in PZM-3 (270 mOsmol) for four days. The DNA methylation status of the Pre-1 sequences in blastocysts was characterized using a bisulfite-sequencing method. Intriguingly, in the present study, we found the unique DNA methylation at several non-CpG sequences at the Pre-1 sequences in all groups. The non-CpG methylation was hypermethylated in all three groups, including in vivo group (86.90% of PZM-3; 83.87% of NaCl; 84.82% of sucrose; 90.94% of in vivo embryos). To determine whether certain non-CpG methylated sites were preferentially methylated, we also investigated the methylation degree of CpA, CpT and CpC. Excepting in vivo group, preference of methylation was CpT>CpC>CpA in all three groups investigated. These results indicate that DNA methylation of Pre-1 sequences was hypermethylated in CpG as well as non-CpG site, regardless modification of osmolarity in a culture media.

• BMB Reports
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• 제40권4호
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• pp.577-587
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• 2007

Single-copy chloroplast loci are used widely to infer phylogenetic relationship at different taxonomic levels among various groups of plants. To test the utility of chloroplast loci and to provide additional data applicable to hybrid evolution in Musa, we sequenced two introns, rpl16 and ndhA, and two intergenic spacers, psaA-ycf3 and petA-psbJ-psbL-psbF and combined these data. Using these four regions, Musa acuminata Cola(A)- and M. balbisiana Colla (B)-containing genomes were clearly distinguished. Some triploid interspecific hybrids contain A-type chloroplasts (the AAB/ABB) while others contain B-type chloroplasts (the BBA/BBB). The chloroplasts of all cultivars in 'Namwa' (BBA) group came from the same wild maternal origin, but the specific parents are still unrevealed. Though, average sequence divergences in each region were little (less than 2%), we propose that petA-psbJ intergenic spacer could be developed for diversity assessment within each genome. This segment contains three single nucleotide polymorphisms (SNPs) and two indels which could distinguish diversity within A genome whereas this same region also contains one SNP and an indel which could categorize B genome. However, an inverted repeat region which could form hairpin structure was detected in this spacer and thus was omitted from the analyses due to their incongruence to other regions. Until thoroughly identified in other members of Musaceae and Zingiberales clade, utility of this inverted repeat as phylogenetic marker in these taxa are cautioned.

• BMB Reports
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• 제51권11호
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• pp.578-583
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• 2018

Telomeres are specialized nucleoprotein complexes that function to protect eukaryotic chromosomes from recombination and erosion. Several telomere binding proteins (TBPs) have been characterized in higher plants, but their detailed in vivo functions at the plant level are largely unknown. In this study, we identified and characterized OsTRFL1 (Oryza sativa Telomere Repeat-binding Factor Like 1) in rice, a monocot model crop. Although OsTRFL1 did not directly bind to telomere repeats $(TTTAGGG){_4}$ in vitro, it was associated with telomeric sequences in planta. OsTRFL1 interacted with rice TBPs, such as OsTRBF1 and RTBP1, in yeast and plant cells as well as in vitro. Thus, it seems likely that the association of OsTRFL1 with other TBPs enables OsTRFL1 to bind to telomeres indirectly. T-DNA inserted OsTRFL1 knock-out mutant rice plants displayed significantly longer telomeres (6-25 kb) than those (5-12 kb) in wild-type plants, indicating that OsTRFL1 is a negative factor for telomere lengthening. The reduced levels of OsTRFL1 caused serious developmental defects in both vegetative and reproductive organs of rice plants. These results suggest that OsTRFL1 is an essential factor for the proper maintenance of telomeres and normal development of rice.

• 한국미생물·생명공학회지
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• 제13권1호
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• pp.19-25
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• 1985

Saccharomyces cerevisiae HIS 5 유전자는 histidinol phosphate aminotransferase (EC: 2, 6, 1,9)를 code하는 아미노산 합성유전자이다. 이 유전자는 plasmid pSH 530에 cloning되어 E. coli와 Saccharomyces cerevisiae 숙주에서 promoter로서 전사하였다. HIS 5 유전자의 총염기 수는 736개이였고 5' 상류영역에는 긴 reading frame, directed repeat, 전사개시점, 그리고 Pribnow box염기배열이 있었다. 특히 HIS 5 유전자의 ATG 주변 염기배열은 -A-A-A-T-T-A-C-A-C-T-A-T-G-G-T-T-T-T-T-G-A-T-였으며 C block은 없었다.