• BMB Reports
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• 제52권8호
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• pp.482-489
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• 2019

Reproductive biotechnology has developed rapidly and is now able to overcome many birth difficulties due to infertility or the transmission of genetic diseases. Here we introduce the next generation of assisted reproductive technologies (ART), such as mitochondrial replacement technique (MRT) or genetic correction in eggs with micromanipulation. Further, we suggest that the transmission of genetic information from somatic cells to subsequent generations without gametes should be useful for people who suffer from infertility or genetic diseases. Pluripotent stem cells (PSCs) can be converted into germ cells such as sperm or oocytes in the laboratory. Notably, germ cells derived from nuclear transfer embryonic stem cells (NT-ESCs) or induced pluripotent stem cells (iPSCs) inherit the full parental genome. The most important issue in this technique is the generation of a haploid chromosome from diploid somatic cells. We hereby examine current science and limitations underpinning these important developments and provide recommendations for moving forward.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.256-263
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• 2006

In the model legume Medicago truncatula, two mutants, sickle and sunn, exhibit morphologically and genetically distinct hypernodulation phenotypes. However, efforts to isolate the single recessive and single semidominant genes for sickle and sunn, respectively, by map-based cloning have so far been unsuccessful, partly due to the absence of clones that enable walks from linked marker positions. To help resolve these difficulties, a new bacterial artificial chromosome (BAC) library was constructed using BamHI-digested genomic fragments. A total of 23,808 clones were collected from ligation mixtures prepared with double-size-selected high-molecular-weight DNA. The average insert size was 116 kb based on an analysis of 88 randomly selected clones using NotI digestion and pulsed-field gel electrophoresis. About 18.5% of the library clones lacked inserts. The frequency of the BAC clones carrying chloroplast or mitochondrial DNA was 0.98% and 0.03%, respectively. The library represented approximately 4.9 haploid M. truncatula genomes. Hybridization of the BAC clone filters with a $C_{0}t-l$ DNA probe revealed that approximately 37% of the clones likely carried repetitive sequence-enriched DNA. An ordered array of pooled BAC DNA was screened by polymerase chain reactions using 13 sequence-characterized molecular markers that belonged to the eight linkage groups. Except for two markers, one to five positive BAC clones were obtained per marker. Accordingly, the sickle- and sunn-linked BAC clones identified herein will be useful for the isolation of these biotechnologically important genes. The new library will also provide clones that fill the gaps between preexisting BAC contigs, facilitating the physical mapping and genome sequencing of M. truncatula.

• IMMUNE NETWORK
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• 제11권1호
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• pp.1-10
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• 2011

Interleukin-7 (IL-7) is an essential cytokine for T cells. However, IL-7 is not produced by T cells themselves such that T cells are dependent on extrinsic IL-7. In fact, in the absence of IL-7, T cell development in the thymus as well as survival of naive T cells in the periphery is severely impaired. Furthermore, modulating IL-7 availability in vivo either by genetic means or other experimental approaches determines the size, composition and function of the T cell pool. Consequently, understanding IL-7 expression is critical for understanding T cell immunity. Until most recently, however, the spatiotemporal expression of in vivo IL-7 has remained obscured. Shortage of such information was partly due to scarce expression of IL-7 itself but mainly due to the lack of adequate reagents to monitor IL-7 expression in vivo. This situation dramatically changed with a recent rush of four independent studies that describe the generation and characterization of IL-7 reporter mice, all utilizing bacterial artificial chromosome transgene technology. The emerging consensus of these studies confirmed thymic stromal cells as the major producers of IL-7 but also identified IL-7 reporter activities in various peripheral tissues including skin, intestine and lymph nodes. Strikingly, developmental and environmental cues actively modulated IL-7 reporter activities in vivo suggesting that IL-7 regulation might be a new mechanism of shaping T cell development and homeostasis. Collectively, the availability of these new tools opens up new venues to assess unanswered questions in IL-7 biology in T cells and beyond.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅲ
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• pp.1303-1306
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• 2003

In this paper, In this paper, we modeled a virtual life(VL) that react to the user's action according to its own behavioral characteristics and grows itself. We established some conditions with which such a VL is designed. Genetic Algorithm is used for the growth process that changes the VL's properties. In this process, the parameter values of the VL's properties are encoded as one chromosome, and the GA operations change this chromosome. The VL's reaction to the user's action is determined by these properties as well as the general expectation of each reaction. These properties are evaluated through 5 fitness measures so as to deal with multi-objective criteria. Here, we present the simulation of the growth process, and show some experimental results.

• Journal of Animal Science and Technology
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• 제64권1호
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• pp.183-186
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• 2022

Lactiplantibacillus plantarum (L. plantarum) ST was isolated from De'ang pickled tea in Yunnan Province, China. The genomes of strain ST were fully sequenced and analyzed using the PacBio RS II sequencing system. Our previous study has shown that L. plantarum ST is a potential probiotic strain. It had strong tolerance in the simulated artificial gastrointestinal tract, and in the antagonism tests, this strain showed strong antibacterial activity. Therefore, as a probiotic, it may be used in animal breeding. L. plantarum ST genome was composed of 1 circular chromosome and 7 plasmids. The length of the whole genome was 3320817 bp, and the annular chromosome size was 3058984 bp, guanine + cytosine (G ± C) content (%) was 44.76%, which contained 2945 protein-coding sequences (CDS). This study will contribute to a further comprehensive understanding of L. Plantarum ST at the genomic level and provide a theoretical basis for its future application in animal breeding.

• 한국양식학회지
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• 제9권2호
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• pp.133-140
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• 1996

경제성이 높은 어종인 무지개송어와 은연어를 대상으로 두 종간의 장점을 갖춘 신품종을 개발하기 위하여 종간 잡종 및 잡종 3배체를 유도하였다. 그 결과, 잡종의 부화율은 $51.7\%$로 여타 대조군에 비해 낮았으나 잡종 3배체의 부화율은 $77.6\%$로 무지개송어 3배체와 유사한 부화율을 보였다. 또한 부화 2개월후의 생존율은 잡종인 경우 $1.7\%$로 매우 낮았으나 잡종 3배체는 $54.5\%$로 무지개송어 3배체의 $56.6\%$ 생존율과 유사하였다. 잡종의 세포 및 핵의 평균 크기는 양친으로 사용된 두 종의 중간을 보였으며 잡종 3배체의 세포 및 핵의 크기는 잡종에 비해 크게 나타났다. 잡종의 염색체수는 60개로 나타나 n=30의 염색체수를 가진 무지개송어 난자와 n= 30의 염색체수를 가진 은연어 정자와 교배된 개체만이 생존력을 갖는 것으로 나타났다. 잡종 3배체의 경우 그의 염색 체수는 $90\~93$개로 Robertsonian형의 전좌에 의한 염색체 다형현상을 보여주었다.

• Journal of Animal Science and Technology
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• 제51권2호
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• pp.123-128
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• 2009

최근 한우의 유전체 연구의 핵심 소재인 박테리아인공염색체(BAC; Bacterial Artificial Chromosome) 클론이 제작되었고 이에 대한 염기서열의 해독과 이를 NCBI (National Center for Biotechnology Information)의 소 유전체 데이터(B_tau 2.1)와 비교 분석하여 한우의 유전체지도 초안(제2 세대 한우유전체지도)이 제작되었다. 본 연구에서는 기존에 확보한 한우의 박테리아인공염색체 클론의 염기서열을 최근에 공개된 소유전체 데이터(B-tau 3.1)와 비교 분석하여 한우 유전체 지도를 최신화하기 위해 실시하였다. 제2 세대 한우유전체지도에서 총 5,105개의 클론에 대한 염색체상 위치가 결정된 반면에 제3세대 한우유전체지도에서는 총 9,595개의 클론에 대한 염색체 위치가 결정되어 약 2배 정도로 향상되었다. 또한 겹치는 부분을 제외했을 때 제3세대 한우유전체지도에 사용된 클론은 소 전체 염색체의 약 37.27%에 해당되는 부분을 커버하는 것으로 나타났다. 앞으로 추가적인 한우 클론의 염기서열 해독을 통해 얻어진 데이터를 확보한다면 한우염색체 정밀 지도의 완성과 이를 이용한 한우 개량에 유용한 유전자 발굴에 활용될 수 있을 것으로 판단되다.

• 한국지능시스템학회논문지
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• 제8권3호
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• pp.1-8
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• 1998

본 논문에서는 유전자 프로그래밍의 성능을 향상시키기 위하여 강화학습법에 기반한 강화 유전자 프로그래밍을 제안한다. 트리구조와 프로그램을 염색체로 가지는 유전자 프로그래밍(GP)은 다른 진화 알고리즘에 비해 염색체의 크기에 제한이 없기 때문에 표현력에 융통성이 많다는 장점이 있다. 그러나 이러한 특징은 반대고 교차 및 돌연변이 연산에 있어서 수렴성을 떨어뜨리는 단점을 나타낸다. 따라서 유전자 프로그래밍은 다른 진화알고리즘에 비해 개체군의 크기 및 진화 세대수를 크게 잡는 것이 일반적이다. 본 논문에서는 유전자 프로그래밍의 이러한 성질을 개선하기 위해서 프로그램에 강화신호를 주어 이것의 보답/벌칙의 정도에 기반한 교차 및 돌연번이 연산을 실행하는 방법을 제안한다. 제안된 방법은 인공개미(Artificial Ant)문제에 적용하여 그 유효성을 입증한다.

• BMB Reports
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• 제44권2호
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• pp.113-117
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• 2011

Previous studies suggest that EphA7 plays a critical role in neural tube closure or cortical progenitor apoptosis. In this report, enhancer trap assay was used to modify various EphA7 BAC clones and screen a large genomic region spanning 570 kb downstream of the EphA7 gene. We found that the dorsal midline-specific EphA7 enhancer resides on the 457D20 EphA7 BAC clone and is localized to a 35 kb genomic region in between +345.7 kb to +379.8 kb downstream of the EphA7 transcription start site. Identification of the EphA7 BAC clone containing a long-range dorsal midline enhancer may constitute a useful tool for investigating the biological functions of EphA7 in vivo.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2003년도 제2차 연례학술대회 발표논문집
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• pp.179-182
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• 2003

The Development of promoter recognition systems is a interesting problem in computational biology. In this paper, we introduce a intelligent system fur promoter recognition with multiple decision models using artificial neural networks. We have trained this models with 1871 human promoter sequences and 5230exon and intron sequences. Our system is found to perform better than other promoter finding systems insensitivity and specificity measures. We have tested our system with Chromosome 22 dataset.