• International Journal of Stem Cells
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• 제16권2호
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• pp.234-243
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• 2023

The recent advances in human pluripotent stem cells (hPSCs) enable to precisely edit the desired bases in hPSCs to be used for the establishment of isogenic disease models and autologous ex vivo cell therapy. The knock-in approach based on the homologous directed repair with Cas9 endonuclease, causing DNA double-strand breaks (DSBs), produces not only insertion and deletion (indel) mutations but also deleterious large deletions. On the contrary, due to the lack of Cas9 endonuclease activity, base editors (BEs) such as adenine base editor (ABE) and cytosine base editor (CBE) allow precise base substitution by conjugated deaminase activity, free from DSB formation. Despite the limitation of BEs in transition substitution, precise base editing by BEs with no massive off-targets is suggested to be a prospective alternative in hPSCs for clinical applications. Considering the unique cellular characteristics of hPSCs, a few points should be considered. Herein, we describe an updated and optimized protocol for base editing in hPSCs. We also describe an improved methodology for CBE-based C to T substitutions, which are generally lower than A to G substitutions in hPSCs.

• 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.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2003년도 제2차 연례학술대회 발표논문집
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• pp.183-192
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• 2003

With the availability of complete whole-genomes such as the human, mouse, fugu and chimpanzee chromosome 22, comparative analysis of large genomes from cross-species at varying evolutionary distances is considered one of a powerful approach for identifying coding and functional non-coding sequences. Here we describe a fast and efficient global alignment method especially for large genomic regions over mega bases pair. We used an approach for identifying all similarity regions by HSP (Highest Segment Pair) regions using local alignments and then large syntenic genome based on the both extension of anchors at HSP regions in two species and global conservation map. Using this alignment approach, we examined rearrangement loci in human chromosome 21 and chimpanzee chromosome 22. Finally, we extracted syntenic genome 30 Mb of human chromosome 21 with chimpanzee chromosome 22, and then identified genomic rearrangements (deletions and insertions ranging h size from 0.3 to 200 kb). Our experiment shows that all jnsertion/deletion (indel) events in excess of 300 bp within chimpanzee chromosome 22 and human chromosome 21 alignments in order to identify new insertions that had occurred over the last 7 million years of evolution. Finally we also discussed evolutionary features throughout comparative analyses of Ka/ks (non-synonymous / synonymous substitutions) rate in orthologous 119 genes of chromosome 21 and 53 genes of MHC-I class in human and chimpanzee genome.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1066-1074
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• 2015

In contrast to high genetic diversity of mitochondrial DNA (mtDNA), equine Y chromosome shows extremely low variability, implying limited patrilines in the domesticated horse. In this study, we applied direct sequencing and restriction fragment length polymorphism (RFLP) methods to investigate the polymorphisms of 33 Y chromosome specific loci in 304 Chinese indigenous horses from 13 breeds. Consequently, two Y-single nucleotide polymorphisms (SNPs) (Y-45701/997 and Y-50869) and one Y-indel (Y-45288) were identified. Of those, the Y-50869 (T>A) revealed the highest variation frequency (24.67%), whereas it was only 3.29% and 1.97% in Y-45288 (T/-) and Y-45701/997 (G>T) locus, respectively. These three mutations accounted for 27.96% of the total samples and identified five Y-SNP haplotypes, demonstrating genetic diversity of Y chromosome in Chinese horses. In addition, all the five YSNP haplotypes were shared by different breeds. Among 13 horse breeds analyzed, Balikun horse displayed the highest nucleotide diversity (${\pi}=5.6{\times}10^{-4}$) and haplotype diversity (h = 0.527), while Ningqiang horse showed the lowest nucleotide diversity (${\pi}=0.00000$) and haplotype diversity (h = 0.000). The results also revealed that Chinese horses had a different polymorphic pattern of Y chromosome from European and American horses. In conclusion, Chinese horses revealed genetic diversity of Y chromosome, however more efforts should be made to better understand the domestication and paternal origin of Chinese indigenous horses.

• 식물분류학회지
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• 제44권4호
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• pp.250-256
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• 2014

본 연구는 3개의 색소체 matK, trnL-F, rbcL DNA 염기서열과 1개의 핵 ITS DNA 염기서열을 근거로 한국산 Aloe 3종 A. arborescens, A. vera 그리고 A. saponaria 등과 하나의 변이종 알로에의 유전적 상관관계를 알고자 수행되었다. 전체 2,420 bp 서열이 증폭되었다. 두 개의 삽인-결실(indel)이 trnL 지역에서 확인되었고, 또한 여러 개의 종 특이적인 염기자위가 전체 29개의 최소변이 정보지역(parsimonious informative site)에서 확인되었다. 조사된 한국산 4 종간에는 148 염기변이 지역이 있었으며, 세계산 Aloe 종들을 포함한 비교해서는 170개의 변이지역 중 75개의 최소변이 지역이 확인되었다. UPGMA를 이용한 phenogram에서 새로운 변이종 알로에는 A. vera와 가장 가깝게 유집되었다. 변이종 알로에는 아직까지 보고된 어떤 종류의 Aloe속내 종과 형태적 및 유전적으로 일치하지 않았다. 조사된 알로에 종들의 유집분석 결과는 기존의 연구결과와 일치하였다.

• 한국발생생물학회지:발생과생식
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• 제18권4호
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• pp.275-286
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• 2014

To successful molecular breeding, identification and functional characterization of breeding related genes and development of molecular breeding techniques using DNA markers are essential. Although the development of a useful marker is difficult in the aspect of time, cost and effort, many markers are being developed to be used in molecular breeding and developed markers have been used in many fields. Single nucleotide polymorphisms (SNPs) markers were widely used for genomic research and breeding, but has hardly been validated for screening functional genes in olive flounder. We identified single nucleotide polymorphisms (SNPs) from expressed sequence tag (EST) database in olive flounder; out of a total 4,327 ESTs, 693 contigs and 514 SNPs were detected in total EST, and these substitutions include 297 transitions and 217 transversions. As a result, 144 SNP markers were developed on the basis of 514 SNP to selection of useful gene region, and then applied to each of eight wild and culture olive flounder (total 16 samples). In our experimental result, only 32 markers had detected polymorphism in sample, also identified 21 transitions and 11 transversions, whereas indel was not detected in polymorphic SNPs. Heterozygosity of wild and cultured olive flounder using the 32 SNP markers is 0.34 and 0.29, respectively. In conclusion, we identified SNP and polymorphism in olive flounder using newly designed marker, it supports that developed markers are suitable for SNP detection and diversity analysis in olive flounder. The outcome of this study can be basic data for researches for immunity gene and characteristic with SNP.

• 생명과학회지
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• 제23권7호
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• pp.847-853
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• 2013

원추리속 식물은 초본류이며 이 속의 일부 종은 약용으로 중요하다. 이 속의 8개 분류군에 대해 엽록체의 rps16-trnK 부위로 계통관계를 평가하였다. 배당된 서열은 원추리(H. aurantiaca)에서 729 핵산 수로 가장 적었으며 왕원추리(H. fulva var. kwanso)에서 742 핵산 수로 가장 많았다. 그 차이는 염기 삽입에 기인하였다. 비록 일부 인델(indel)과 20개 염기의 삽입이 발견되었지만 서열 내 변이는 염기 치환이 많았다. rps16 - trnK에 의한 한국내 원추리속 분류군들은 높은 지지도로 잘 분리되었다. 애기원추리(H. minor)와 홍도원추리(H. littorea)는 높은 지지도로 같은 분지군을 형성하였으며 이 분지군은 노랑원원추리와 자매군을 형성하였다. 염색체의 수는 기존 보고된 RAPD의 결과와는 일치하지 않으나 본 연구와는 일치하였다.

• Genomics & Informatics
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• 제3권4호
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• pp.142-148
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• 2005

The immune response-related genes have been suggested to be the most favorable genes for positive selection during evolution. Comparing the entire DNA sequence of chimpanzee chromosome 22 (PTR22) with human chromosome 21 (HSA21), we have identified 15 orthologs having indel in their coding sequences. Among them, interferon-${\alpha}$ receptor-1 gene (IFNAR1), an immuneresponse-related gene, is subjected to comparative genomic analysis. Chimpanzee IFNAR1 showed the same genomic structure as human IFNAR1 (11 exons and 10 introns) except the 3 bp insertion in exon 4. The sequence alignment of IFNAR1 coding sequence indicated that 'ISPP' amino acid sequence motif is highly conserved in chimpanzee and other animals including mouse and chicken. However, the human IFNAR1 shows that one proline residue is missing in the sequence motif. The homology modeling of the IFNAR1 structures suggests that the proline deletion in human IFNAR1 leads to the formation of the following ${\alpha}$-helix, whereas two sequential prolines in chimpanzee IFNAR1 inhibit it. As a result, human IFNAR1 may adopt a characteristic structure distinct from chimpanzee IFNAR1. This human specific trait could contribute to specific immune response in the most optimized manner for humans. Further molecular biological studies on the IFNAR1 will help us to gain insights into the molecular implication of species-specific host-pathogen interaction in primate evolution.

• 한국균학회지
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• 제49권1호
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• pp.33-44
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• 2021

본 연구에서는 국내에 유통되고 있는 40개 표고 품종들로부터 산백향과 설백향의 구분이 가능한 CAPS 마커를 개발하였다. 제한효소 Hha I 과 HpyCH4IV를 이용한 밴드 패턴 분석을 통해 각각 산백향과 설백향을 다른 균주들과 구분하여 구별성을 확보할 수 있었다. 본 연구에서 개발된 CAPS 마커는 표고의 품종들 간에 유전적 다양성을 부여함으로써, 품종을 보호할 수 있는 분자생물학적 근거가 될 수 있다. 이로써 향후 유전자원에 대한 국가간 분쟁을 미연에 방지할 수 있을 것이다.

• 대한본초학회지
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• 제34권6호
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• pp.91-97
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• 2019

Objective : To establish a reliable tool between for the distinction of original plants of Sanguisorbae Radix, we analyzed the complete chloroplast genome sequence of Sanguisorbae Radix and identified single nucleotide polymorphisms (SNPs). Materials and methods : The chloroplast genome sequence of Sanguisorba officinalis, Sanguisorba tenuifolia f. alba (Trautv. & Mey.) Kitam and Sanguisorba tenuifolia Fisch. ex Link obtained using next-generation sequencing technology were described and compared with those of other species to develop specific markers. Candidate genetic markers were identified to distinguish species from the chloroplast sequences of each species using Modified Phred Phrap Consed and CLC Genomics Workbench programs. Results : The structure of the chloroplast genome of each sample that had been assembled and verified was circular, and the length was about 155 kbp. Through comparative analysis of the chloroplast sequences, we found 220 nucleotides, 158 SNPs, and 62 Indel (insertion and/or deletion), to distinguish Sanguisorba officinalis, Sanguisorba tenuifolia f. alba (Trautv. & Mey.) Kitam and Sanguisorba tenuifolia Fisch. ex Link. Finally, 15 specific SNP genetic markers were selected for the verification at positions. Avaliable primers for the dried herb, which is used as medicine, were used to develop the PCR amplification product of Sanguisorbae Radix to assess the applicability of PCR analysis. Conclusion : In this study, we found that Fendel-qPCR analysis based on the chloroplast DNA sequences can be an efficient tool for discrimination of Sanguisorba officinalis, Sanguisorba tenuifolia f. alba (Trautv. & Mey.) Kitam and Sanguisorba tenuifolia Fisch. ex Link.