• Asian-Australasian Journal of Animal Sciences
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• 제14권3호
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• pp.302-306
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• 2001

This study was carried out to construct mapping population and to evaluate the methods involved, including polymorphic DNA marker system and appropriate statistical analysis. As an initial step to establish chicken genome mapping project, White Leghorn (WL) and Korean Ogol chicken (KOC) were used for generating backcross population. From 8 initial parents, total 280 backcross progenies were obtained and 40 were used for genotyping and linkage analysis. For development of novel polymorphic markers for KOC, Random Amplified Polymorphic DNA (RAPD) markers specific for this chicken line were generated. Also included in this study were six microsatellite markers from East Lansing map as reference loci. For segregation analysis, 15 RAPD markers and 6 microsatellites were used to genotype the backcross population. Among the RAPD markers that we developed, 2 pairs of markers were identified to be linked and another 4 RAPD markers showed linkage with microsatellites of known map. In summary, this study showed that our backcross population generated from the mating of KOC to WL serves as a valuable genetic resource for genotyping. Furthermore, RAPD markers are proved to be valuable in linkage mapping analysis.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.598-605
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• 2015

The cohesin complex holds sister chromatids together and prevents premature chromosome segregation until the onset of anaphase. Mcd1 (also known as Scc1), the α-kleisin subunit of cohesin, is a key regulatory subunit of the mitotic cohesin complex and is required for maintaining sister chromatid cohesion, chromosome organization, and DNA repair. We investigated the function of Mcd1 in meiosis by ectopically expressing Mcd1 during early meiotic prophase I in Saccharomyces cerevisiae. Mcd1 partially regulated the progression of meiotic recombination, sister chromatid separation, and nuclear division. DNA physical analysis during meiotic recombination showed that Mcd1 induced double-strand breaks (DSBs) but negatively regulated homologous recombination during DSB repair; Mcd1 expression delayed post-DSB stages, leading to inefficiencies in the DSB-to-joint molecule (JM) transition and subsequent crossover formation. These findings indicate that meiotic cells undergo Mcd1-mediated DSB formation during prophase I, and that residual Mcd1 could regulate the progression of JM formation during meiotic recombination.

• 한국미생물·생명공학회지
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• 제18권6호
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• pp.560-565
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• 1990

Trichocderma koningii의 영양요구성 돌연변이주인 CUT 121로부터 얻은 원형질체를 야생형인 ATCC 26113의 핵과 혼합하여 PEG 용액을 처리한 결과, 독립 영양형의 형질전환체가 30 이상의 빈도로 생성되었다. 이 독립영양형 군체로부터 얻은 분리체 중의 하나는 xylanase의 활성이 야생형보다 3배 가량 증진되었으며, 다른 세포의 다당류 분해효소는 야생형과 유사한 수준을 나타내었다. 분리체의 DNA 함량, 인위적인 불리양상 및 동위효소 양상 등을 조사 분석한 결과, 독립영양형의 형질전환체는 실험에 사용된 형질전환체로 판명되었다. 이상의 결과로 Trichoderma속 균류의 균주개량법으로, 핵전이법이 통상의 원형질체 융합법보다 효율적인 것으로 판명되었다.

• KSBB Journal
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• 제5권3호
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• pp.255-261
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• 1990

Astaxanthin을 생산하는 효모 Phaffia rhodozyma로부터 제조된 상보적 돌연변이 균주간의 세포융합을 통하여 astaxanthin을 대량 생산하는 균주를 얻고자 시도하였다. 이들의 원형질체 융합빈도는 $1.3$\times$10^-^5-6.0$\times$10^-^5$이었고 DNA함량, 핵염색, UV조사에 대한 생존력 비교 그리고 형질분리분석등으로 핵융합을 확인하였다. 융합체 중 F1은 야생형의 모 균주와 비교했을때 astaxanthin생성량이 약 3배 증가하였다.

• Molecules and Cells
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• 제20권2호
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• pp.201-209
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• 2005

We have constructed an AFLP-based linkage map of Japanese red pine (Pinus densiflora Siebold et Zucc.) using haploid DNA samples of 96 megagametophytes from a single maternal tree, selection clone Kyungbuk 4. Twenty-eight primer pairs generated a total of 5,780 AFLP fragments. Five hundreds and thirteen fragments were verified as genetic markers with two alleles by their Mendelian segregation. At the linkage criteria LOD 4.0 and maximum recombination fraction 0.25(${\theta}$), a total of 152 markers constituted 25 framework maps for 19 major linkage groups. The maps spanned a total length of 2,341 cM with an average framework marker spacing of 18.4 cM. The estimated genome size was 2,662 cM. With an assumption of equal marker density, 82.2% of the estimated genome would be within 10 cM of one of the 230 linked markers, and 68.1% would be within 10 cM of one of the 152 framework markers. We evaluated map completeness in terms of LOD value, marker density, genome length, and map coverage. The resulting map will provide crucial information for future genomic studies of the Japanese red pine, in particular for QTL mapping of economically important breeding target traits.

• BMB Reports
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• 제47권6호
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• pp.299-310
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• 2014

Cohesin is a multi-protein complex composed of four core subunits (SMC1A, SMC3, RAD21, and either STAG1 or STAG2) that is responsible for the cohesion of sister chromatids following DNA replication until its cleavage during mitosis thereby enabling faithful segregation of sister chromatids into two daughter cells. Recent cancer genomics analyses have discovered a high frequency of somatic mutations in the genes encoding the core cohesin subunits as well as cohesin regulatory factors (e.g. NIPBL, PDS5B, ESPL1) in a select subset of human tumors including glioblastoma, Ewing sarcoma, urothelial carcinoma, acute myeloid leukemia, and acute megakaryoblastic leukemia. Herein we review these studies including discussion of the functional significance of cohesin inactivation in tumorigenesis and potential therapeutic mechanisms to selectively target cancers harboring cohesin mutations.

• Journal of Microbiology and Biotechnology
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• 제2권1호
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• pp.46-49
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• 1992

The availability of Phaffia rhodozyma as an astaxanthin sources in the aquaculture industry is limited because of the low carotenoid content of natural isolate. In this study, we have used the protoplast fusion technique to construct cell hybrids with an increased content of astaxanthin from P. rhodozyma. Cell hybrids (F307 and F406) obtained were very stable and produced considerably more astaxanthin (> 1 mg/g yeast) than the wild parent. Karyogamy was confirmed by the isolation of recombinants after mitotic segregation of parental auxotrophic genetic markers, the increased amount of chromosomal DNA/cell and the presence of single nucleus/cell.

• 한국자원식물학회지
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• 제10권3호
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• pp.247-249
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• 1997

Seed protein and oil content is important trait in the soybean. Both seed protein and oil content in this plant species is inherited quantitatively. A 68-plant $F_2$ segregation population derived from a mating between Mercury and PI 467.468 was evaluated with random amplified polymorphic DNA (RAPD) markers to identify QTL related to seed protein and oil content. Marker OPB12 was found to be associated with differences in seed protein content. Four markers, OPA09b, OPM07b, OPC14, and OPN11b had highly significant effects on seed oil content. By interval mapping, the interval between marker OPK3c and OPQ1b on linkage group 13 contained a QTL that explained 25.7% variation for seed oil content.

• Molecules and Cells
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• 제27권2호
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• pp.135-142
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• 2009

The centrosome, an organelle comprising centrioles and associated pericentriolar material, is the major microtubule organizing center in animal cells. For the cell to form a bipolar mitotic spindle and ensure proper chromosome segregation at the end of each cell cycle, it is paramount that the cell contains two and only two centrosomes. Because the number of centrosomes in the cell is determined by the number of centrioles, cells have evolved elaborate mechanisms to control centriole biogenesis and to tightly coordinate this process with DNA replication. Here we review key proteins involved in centriole assembly, compare two major modes of centriole biogenesis, and discuss the mechanisms that ensure stringency of centriole number.

• Molecules and Cells
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• 제45권5호
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• pp.273-283
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• 2022

During meiosis, homologous chromosomes (homologs) pair and undergo genetic recombination via assembly and disassembly of the synaptonemal complex. Meiotic recombination is initiated by excess formation of DNA double-strand breaks (DSBs), among which a subset are repaired by reciprocal genetic exchange, called crossovers (COs). COs generate genetic variations across generations, profoundly affecting genetic diversity and breeding. At least one CO between homologs is essential for the first meiotic chromosome segregation, but generally only one and fewer than three inter-homolog COs occur in plants. CO frequency and distribution are biased along chromosomes, suppressed in centromeres, and controlled by pro-CO, anti-CO, and epigenetic factors. Accurate and high-throughput detection of COs is important for our understanding of CO formation and chromosome behavior. Here, we review advanced approaches that enable precise measurement of the location, frequency, and genomic landscapes of COs in plants, with a focus on Arabidopsis thaliana.