• 식물분류학회지
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• 제48권4호
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• pp.260-277
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• 2018

The evolution of chromosome numbers and the karyotype structure is a prominent feature of plant genomes contributing to or at least accompanying plant diversification and eventually leading to speciation. Polyploidy, the multiplication of whole chromosome sets, is widespread and ploidy-level variation is frequent at all taxonomic levels, including species and populations, in angiosperms. Analyses of chromosome numbers and ploidy levels of 252 taxa of Korean non-commelinid monocots indicated that diploids (ca. 44%) and tetraploids (ca. 14%) prevail, with fewer triploids (ca. 6%), pentaploids (ca. 2%), and hexaploids (ca. 4%) being found. The range of genome sizes of the analyzed taxa (0.3-44.5 pg/1C) falls well within that reported in the Plant DNA C-values database (0.061-152.33 pg/1C). Analyses of karyotype features in angiosperm often involve, in addition to chromosome numbers and genome sizes, mapping of selected repetitive DNAs in chromosomes. All of these data when interpreted in a phylogenetic context allow for the addressing of evolutionary questions concerning the large-scale evolution of the genomes as well as the evolution of individual repeat types, especially ribosomal DNAs (5S and 35S rDNAs), and other tandem and dispersed repeats that can be identified in any plant genome at a relatively low cost using next-generation sequencing technologies. The present work investigates chromosome numbers (n or 2n), base chromosome numbers (x), ploidy levels, rDNA loci numbers, and genome size data to gain insight into the incidence, evolution and significance of polyploidy in Korean monocots.

• 한국환경성돌연변이발암원학회지
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• 제18권2호
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• pp.109-115
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• 1998

Fluorscence in situ hybridization with chromosome-specific probe has been shown to be a valid and rapid method for detection of chromosome rearrangements induced by chemical and physical agents. This method is useful for quantifying structural aberrations, expecially for stable ones, such as translocation and insertion, which are difficult to detect with conventional method in human lymphocyte. In order to use the FISH method as a biodosimeter for monitoring human population exposed to various chemical and physical agent, baseline level of chromosome rearragement was established. Blood from forty four healthy adults were collected and analysed with whole chromosome-specific probes by human chromosome 1,2 and 4. The frequencies of stable translocation were 2.45 per 100 cell equivalent and those of insertion, color juction, acentric and dicentric were 0.32, 3.28, 0.23 and 0.27 per 100 cell equivalent respectively. The frequencies of chromosome rearragements increased with age in both sexes except for dicenrics. From above result, stable aberrations accumulate with age and it may reflect integrated lifetime exposure of adverse environment.

• 한국동물학회지
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• 제6권2호
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• pp.21-27
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• 1963

This study is concerned with alterations in chromosomes (numbers and morphology) when the culture of Chinese hamster cells (FAF-28 strain) was treated by steroids, testosterone and DOC. 1. In 200 cells of normal untreated cells as control population the chromosome of stemline was decided as which was contained in 158 cells ; that is , in 79 percent of the population. The average chromosome number in above 20 cells observed was calculated as 23.95 with minimum limit at 20 and maximum limit at 70. 2. Many different chromosome numbers, ranging from 19 to 352 were observed in the 200 cells treated by testosterone. The diploid number of 22 showed the peak of variation curve was counted in 71 cells (35.5%) and an average chromosome number of stemline was 22 which was counted in 74 cells (37%). While all of the chromosome number of stemline was 22 which was counted in 74 cells (37%). While all of the chromosome numbers in the 200 cells observed ranged from 20 to 181 , an average chromosome number was also found to be 30.09. 4. The chromosome component in the cultured normal FAF-28 cells with 22 diploid chromosomeswas as follows ; 9a) 2 paris were long and metacentric (LM), (b) 3 pairs were medium length and metacentric (MM), (c) 3 pairs were small and subtelocentric (SS) and (d) 3 pairs were small and metacentric (SM). 5. The twenty cells with 44 chromosomes were selected at random from each cell population treated with testosterone and DOC , so that chromosome idiogram and morphology could be studies. In the twenty cells of the testosterone treated population the average ratio of above four groups, LM ; MM;Ss:SM, was found to be 8.6 : 10.8:13.5:10.7. On the other hand, the average ratio in the same number of cells of the DOC treated one was 7.7 :11.4:12.5:12.7. 6. The five types of the altered chromosomes morphologically in the hundred cells selected at random from each cell population treated by testosterone and DOC were observed (Type I-V). The thirty-one altered chromosomes were found to be in the testosterone treated cell population and the sixteen in DOC treated.

• Parasites, Hosts and Diseases
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• 제36권4호
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• pp.277-279
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• 1998

우리 나라 인체 장흡충의 하나인 서울주걱흡충의 염색체 핵형 분석을 위하여 고환에서 압착법으로 염색체를 분리하여 관찰하였다. 분석 결과 n=10, 2n=20이며, 2쌍의 중앙중심절 염색체 (metacentric chromosome), 5쌍의 아래중앙중심절/아래끝중심절 염색체 (submetacentr$ic_telocentric chromosome), 3쌍의 끝중심절 염색체 (telocentric chromosomes)로 구성되어 있었다. 이 결과는 앞으로 게놈 연구 등의 기본 자료로 쓰일 수 있을 것이다.이다.

• 한국환경성돌연변이발암원학회지
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• 제16권2호
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• pp.88-96
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• 1996

Fluorescence in situ hybridization (FISH) with the DNA probe for human chromosome 4 was used to analyse in vitro radiation induced chromosome rearrangement in peripheral lymphocyte. Translocations, dicentrics, acentrics and color junctions involving the painted chromosome were scored according to the Protocol for Aberration Identification and Nomenclature Terminology (PAINT) system. The frequency of chromosome rearrangements including reciprocal translocation, dicentric, acentric fragment and color junction increased with radiation dose. The frequency of dicentric chromosome reduced by the fixation time following irradiation, whereas that of translocation was relatively persistent. The applicability of FISH for scoring stable translocation for biological dosimetry was demonstrated.

• Journal of Plant Biology
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• 제36권3호
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• pp.281-284
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• 1993

A karyotype of cytotype BB plant in Scilla scilloides Complex was established and the frequency of B-chromosomes were investigated. Chromosome complements of BB genome were composed of five pairs of subtelocentric and four pairs of metacentric chromosomes. Chromosome 1 has satellite with nucleolar organizer. Polymorphism was found in chromosome 2. The karyotype of cytotype BB will be available for analysis of genome composition in various cytotypes of S. scilloides Complex. The frequency of B-chromosome was 78.6%. Numbers of B-chromosome ranged from 1 to 4 and plants with 2B-chromosomes were predominant (57.2%). Two type of B-chromosomes, F and F', were found; F is a large iso-chromosome and F' a small one.

• 미생물학회지
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• 제29권1호
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• pp.69-73
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• 1991

The chromosome of Fusarium species during the vegetatve nuclear divisions in hyphae were observed by use of HCl-Giemsa technique on light microscope. The haploid chromosome number of Fusarium anthophilum 7472 was n=7, n=6 in F. anthophilum 7481 and n=6 in F. oxysporum 7500. The haploid chromosome number was 7 in F. napiforme 6129 and F. napiforme 6144. Those of F. caucasicum F. caucasicum ATCC 18791 and F. aquaeductuum ATCC 15612 were n=5. F. coeruleum ATCC 20088 was n=6, n=8 in F. camptoceras ATCC 16065 and n=7 in F. sambucinum NRRL 13451. From these results and previous papers, it may be concluded that the basic haploid chromosome number of the genus Fusarium is n=4.

• Genomics & Informatics
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• 제4권2호
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• pp.80-86
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• 2006

It is clear that the construction of large insert DNA libraries is important for map-based gene cloning, the assembly of physical maps, and simple screening for specific genomic sequences. The bacterial artificial chromosome (BAC) system is likely to be an important tool for map-based cloning of genes since BAC libraries can be constructed simply and analyzed more efficiently than yeast artificial chromosome (YAC) libraries. BACs have significantly expanded the size of fragments from eukaryotic genomes that can be cloned in Escherichia coli as plasmid molecules. To facilitate the isolation of molecular-biologically important genes in Ashbya gossypii, we constructed Ashbya chromosome-specific BAC libraries using pBeloBAC11 and pBACwich vectors with an average insert size of 100 kb, which is equivalent to 19.8X genomic coverage. pBACwich was developed to streamline map-based cloning by providing a tool to integrate large DNA fragments into specific sites in chromosomes. These chromosome-specific libraries have provided a useful tool for the further characterization of the Ashbya genome including positional cloning and genome sequencing.

• 한국가축번식학회지
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• 제15권2호
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• pp.87-95
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• 1991

The chromosome analyses of blood culture were made of 11 Korean native and 53 crossbred males between the Korean native cattles(K) and Charolais(C), which consisted of $K\times$K, $C\times$K, $C\times$CK, CK$\times$CCK and Charolais synthetic males(CK$\times$CCK or CCK$\times$CK). 1. The diploid(2n=60, XY) Charolais synthetic male has the 29 pairs of acrocentric autosomes, a single large submetacentric X and a small metacentric Y chromosome. 2. The numbers of G-band of karyotype in these males were a few differences in the 8 pairs of autosomes(chromosome 2, 4, 5, 6, 9, 11, 19 and 26) compared to those of purebred Korean native ones. G-banding qualities were not matched in chromosome 16, 19 and 29 with the Korean native males and also in chromosome 14, 20 and 22 with other domestic cattles. 3. The G-banding pattern between chromosome 4-6-7 and 24-25-27 was alomost similar together and the possibilityof misidentification was greater in the G-banded preparations. 4. 1/29 Robertsonian translocation and other abnormalities were not observed among 11 Korean native and 53 crossbred males. This result is considered in relation to limited data and further investigation based on larger samples may be necessary for definite conclusion.

• Journal of Microbiology and Biotechnology
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• 제25권7호
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• pp.1026-1035
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• 2015

Condensin is not only responsible for chromosome condensation, but is also involved in double-strand break (DSB) processing in the cell cycle. During meiosis, the condensin complex serves as a component of the meiotic chromosome axis, and mediates both proper assembly of the synaptonemal complex and DSB repair, in order to ensure proper homologous chromosome segregation. Here, we used the budding yeast Saccharomyces cerevisiae to show that condensin participates in a variety of chromosome organization processes and exhibits crucial molecular functions that contribute to meiotic recombination during meiotic prophase I. We demonstrate that Ycs4 is required for efficient DSB formation and establishing homolog bias at the early stage of meiotic prophase I, which allows efficient formation of interhomolog recombination products. In the Ycs4 meiosis-specific allele (ycs4S), interhomolog products were formed at substantial levels, but with the same reduction in crossovers and noncrossovers. We further show that, in prophase chromosomal events, ycs4S relieved the defects in the progression of recombination interactions induced as a result of the absence of Rec8. These results suggest that condensin is a crucial coordinator of the recombination process and chromosome organization during meiosis.