• Korean Journal of Medicinal Crop Science
• /
• v.12 no.5
• /
• pp.401-405
• /
• 2004

Karyotypes were established in the eight Korean native species of the genus Iris. Chromosome numbers were 2n=50 in I. koreana and 2n=42 in I. uniflora var. carinata and their karyotype formulas were K = 2n = 50 = 14m + 28sm + 8st and K = 2n = 42 = 16m + 26sm, respectively. I. dichotoma and I. pseudoacorus were diploids of 2n=34. However, they showed different karyotype formulas: K = 2n = 34 = 26m + 6sm + 2st in I. dichotoma and K = 2n = 34 = 8m + 24sm + 2st in I. pseudoacorus. I. setosa, and I. pallasii var. chinensis carried the same chromosome numbers of 2n=40, but they showed different patterns of karyotype formula: K = 2n = 40 = 22m + 14sm + 4st in I. setosa and K = 2n = 40 = 26m + 12sm + 2st in I. pallasii var. chinensis. I. sanguinea was a diploid of 2n=28 and the karyotype formula was K = 2n = 28 = 14m + 14sm. I. ensata var. spontanea was a diploid of 2n=24 and the karyotype formula was K = 2n = 24 = 10m + 14sm. Each species showed characteristic chromosome composition with a pair of satellite chromosome except I. koreana with three pairs of satellite chromosomes. The chromosomes of I. dichotoma and I. uniflora were comparatively short, while the chromosomes of I. ensata were remarkably bigger than those of other species. These cytological data will give a useful information for the identification and breeding program of the Iris plants.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.9
• /
• pp.1378-1386
• /
• 2020

Objective: Chinese indigenous sheep breeds can be classified into the following three categories by their tail morphology: fat-tailed, fat-rumped and thin-tailed sheep. The typical sheep breeds corresponding to fat-tailed, fat-rumped, and thin-tailed sheep are large-tailed Han, Altay, and Tibetan sheep, respectively. Detection of copy number variation (CNV) and selection signatures provides information on the genetic mechanisms underlying the phenotypic differences of the different sheep types. Methods: In this study, PennCNV software and F-statistics (F_ST) were implemented to detect CNV and selection signatures, respectively, on the X chromosome in three Chinese indigenous sheep breeds using ovine high-density 600K single nucleotide polymorphism arrays. Results: In large-tailed Han, Altay, and Tibetan sheep, respectively, a total of six, four and 22 CNV regions (CNVRs) with lengths of 1.23, 0.93, and 7.02 Mb were identified on the X chromosome. In addition, 49, 34, and 55 candidate selection regions with respective lengths of 27.49, 16.47, and 25.42 Mb were identified in large-tailed Han, Altay, and Tibetan sheep, respectively. The bioinformatics analysis results indicated several genes in these regions were associated with fat, including dehydrogenase/reductase X-linked, calcium voltage-gated channel subunit alpha1 F, and patatin like phospholipase domain containing 4. In addition, three other genes were identified from this analysis: the family with sequence similarity 58 member A gene was associated with energy metabolism, the serine/arginine-rich protein specific kinase 3 gene was associated with skeletal muscle development, and the interleukin 2 receptor subunit gamma gene was associated with the immune system. Conclusion: The results of this study indicated CNVRs and selection regions on the X chromosome of Chinese indigenous sheep contained several genes associated with various heritable traits.

• Korean Journal of Animal Reproduction
• /
• v.21 no.3
• /
• pp.229-238
• /
• 1997

Chromosome condensation and swelling of the donor nucleus have been known as the early morphological indicators of chromatin remodelling after injection of a foreign nucleus into an enucleated recipient cytoplasm. The effects of non-preactivation and electrical preactivation of recipient cytoplasm, prior to fusing a donor nucleus, on the profile of nuclear remodelling in the nuclear transplant rabbit embryos were evaluated. The embryos of 16-cell stage were collected and synchronized to G1 phase of 32-cell stage. The recipient cytoplasms were obtained by removing the first polar body and chromosome mass by non-disruptive microsurgical procedure. The separated G1 phase blastomeres of 32-cell stage were injected into non-preactivated recipient cytoplasms. Otherwise, the enucleated recipient cytoplasms were preactivated by electrical stimulation and the separated G1 phase blastomeres of 32-cell stage were injected. After culture until 20h post-hCG injection, the nuclear transplant oocytes were electrofused by electrical stimulation. The nuclei of nuclear transplant embryos fused into non-preactivated and/or preactivated recipient cytoplasm were stained by Hoechst 33342 at 0, 1.5, 2, 4, 6, 8, 10 hrs post-fusion and were observed under an fluorescence microscopy. Accurate measurements of nuclear diameter were revealed with an ocular micrometer at 200$\times$. Upon blastomere fusion into non-preactivated recipient cytoplasm, a prematurely chromosome condensation at 1.5 hrs post-fusion and nuclear swelling at 8 hrs post-fusion were occurred as 91.6% and 86.1%, respectively. But the nuclei of nuclear transplant embryos fused into preactivated recipient cytoplasm, as o, pp.sed to non-preactivated recipient cytoplasm, were not occurred chromosome condensation and extensive nuclear swelling. Nuclear diameter fused into non-preactivated and preactivated recipient cytoplasm at hrs post-fusion was 30.2$\pm$0.74 and 15.2$\pm$1.32${\mu}{\textrm}{m}$, respectively. These results indicated that onset of unclear condensation and swelling which was associated with oocytes activation were critical steps in the process of chromatin swelling. Futhermore, complete reprogramming seemed only possible after remodelling of the donor nucleus by chromosome condensation and nuclear swelling.

• Archives of Pharmacal Research
• /
• v.16 no.3
• /
• pp.196-204
• /
• 1993

Flavonol derivatives were tested for their anticlastogenic effect against induction of micronuclei by n-methyl-n'-nitor-n-nitorsoguanidine(MNNG), and against induction of chromosome aberration by bleomycin or MNNG.belomycin. For micronudeus assay, each flavonol derivative (0, 0.001, 0.01, 0.1, 1, 10 and 100 mg/kg) was administered orally twice with 24 h interval, together with intraperitioneally administered MNNG(150 mg/kg). The result showed that msot flavonol derivatives tested were effective in suppresing the frequencies of micronude induced by MNNG. For chromosome aberration assy, each flavonol derivative (0, 0.1, 1, 10m and 100 mg/kg)was administered to mice orally in vivo, and then mice were sacrificed and spleen lymphocyte cultures were made. Bleomycin $(3\;\mu$g/ml) was treated to the mouse spleen hymphocyte cultures at 24 h after con A initiation. There wre nomarked decrease tendencies in chromosome aberration unless all doses of galangin and some doses of several flavonol derivatives tested. In the another experiment, we have evaluated the effect of flavonol derivatives on the enhancement of bleomycin-induced chromsome aberration by MNNG. Most of flavonol derivtives reduced the incidence of chromosome aberration induced by in vitro treatment of bleomycin followed by in vivo treatment of MNNG. Galangin particulary showed a dose-dependent decrease tendency. Other flavonol derivative showed slightly suggest that most of flavonol derivatives may be capable of protecting the inhibition of suggest that most of flavonol derivatives may be capable of protecting the inhibition of DNA-repair by MNNG. Our data indicate clearly that flavonol derivatives can suppress MNNG-induced genotoxicity such as an induction of MNPCEs. Therfore, our results could suggest that flavonol derivtives may be useful as a chemopreventive agent of MNNG.

• Journal of Microbiology and Biotechnology
• /
• v.22 no.2
• /
• pp.184-189
• /
• 2012

We sought to breed an industrially useful yeast strain, specifically an ethanol-tolerant yeast strain that would be optimal for ethanol production, using a novel breeding method, called genome reconstruction, based on chromosome splitting technology. To induce genome reconstruction, Saccharomyces cerevisiae strain SH6310, which contains 31 chromosomes including 12 artificial mini-chromosomes, was continuously cultivated in YPD medium containing 6% to 10% ethanol for 33 days. The 12 mini-chromosomes can be randomly or specifically lost because they do not contain any genes that are essential under high-level ethanol conditions. The strains selected by inducing genome reconstruction grew about ten times more than SH6310 in 8% ethanol. To determine the effect of mini-chromosome loss on the ethanol tolerance phenotype, PCR and Southern hybridization were performed to detect the remaining mini-chromosomes. These analyses revealed the loss of mini-chromosomes no. 11 and no. 12. Mini-chromosome no. 11 contains ten genes (YKL225W, PAU16, YKL223W, YKL222C, MCH2, FRE2, COS9, SRY1, JEN1, URA1) and no. 12 contains fifteen genes (YHL050C, YKL050W-A, YHL049C, YHL048C-A, COS8, YHLComega1, ARN2, YHL046W-A, PAU13, YHL045W, YHL044W, ECM34, YHL042W, YHL041W, ARN1). We assumed that the loss of these genes resulted in the ethanol-tolerant phenotype and expect that this genome reconstruction method will be a feasible new alternative for strain improvement.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2019.10a
• /
• pp.24-24
• /
• 2019

Iris L. is a perennial genus comprising approximately 300 species worldwide, with the greatest number of endemic species occurring in Asia. Iris is one of the largest genera in the family Iridaceae and includes ca. 15 species native to Korea. Although chromosome number change, karyotype restructuring, and genome size variation play an important role in plant genome diversification, understanding the karyotype variation in Korean Iris species has been hampered by the wide range of base chromosome number (x = 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22) reported to date. This study documents the chromosome numbers, karyotype structure and genome size variation in Iris ruthenica K. Gawl., an endangered species in Korea obtained using classic Feulgen staining and flow cytometry. The chromosome number of all investigated plants from the nine populations was 2n = 42. All individuals studied possessed metacentric and submetacentric chromosomes. The genome size of the I. ruthenica in eight wild populations ranged from 2.39 pg/1C to 2.45 pg/1C ($2.42{\pm}0.02pg/1C$: $mean{\pm}SD$). This study provides the first report of genome size variation in Iris ruthenica in Korea. This study lays foundation for cytogenetic further analyses employing by fluorescence in situ hybridization (FISH) to better understand the chromosomal evolution in this species and in the whole genus.

• Korean Journal of Plant Resources
• /
• v.16 no.1
• /
• pp.55-60
• /
• 2003

The genetic variation of random amplified polymorphic DNA (RAPD) patterns of genomic DNAs was investigated in dioecious plant Rumex acetosa L., which carries different sex chromosome complements in female (2n=12A+XX) and male (2n=12A+XY$_1$Y$_2$). One hundred and twenty random primers consisted of 10-mer were used for PCR amplification. Polymorphic bands were found in 24 primers. Specific bands for female and male were 16 and 18, respectively. Especially, a band of 1,440 bp from the OPC-10 primer was male specific. These sex specific RAPD markers are used to understanding the sex determination mechanism in plants.

• Korean Journal of Poultry Science
• /
• v.16 no.4
• /
• pp.201-207
• /
• 1989

This study was carried out to identify the chromosome morphological structure and G-, C-banding pattern of Korean native fowl. The samples used in this study were early chick embryos, and the method of chromosomal analysis quoted from the protocal of Ohio univ. with more or less modified. The results were summerized as follow as； 1. In each of macrochromosomal morphology, the arm-ratio, centromeric index, and relative length of Korean native fowl were more or less different from improved breeds, but the designations were the same. 2. The graphical pecks, by densitometric recordings, in each macrochromosome number of 1, 2, 3, 4, Z, and 5, numbered 21, 14, 12, 8, 11, and 4 in G-banded, and 16, 13, 9, 9, 9, and 4 in C-banded, respectively. Those pecks could be explained as a consequence of chromosome condensation during mitosis and of genetic material differences.

• Korean Journal of Medicinal Crop Science
• /
• v.12 no.6
• /
• pp.490-493
• /
• 2004

Karyotypes were established in five Pulsatilla species from Korea : P. cernua, P. davurica, P. koreana, P. chinensis and P. tongkangensis. The somatic chromosome numbers of five species were all 2n=2x=16 with the basic number of x=8. The chromosome complement of P. cernua consisted of 5 pairs of metacentric, 1 pair of submetacentric and 2 pairs of subtelocentric. P. davurica, P. koreana and P. chinensis consisted of 5 pairs of metacentric and 3 pairs of subtelocentric. P. tongkangensis consisted of 5 pairs of metacentric, 2 pairs of submetacentric, and 1 pair of subtelocentric. Karyotype formulas of P. davurica, P. koreana, and P. chinensis were the same as K (2n) = 2x = 16 = 10m + 6st, while those of P. cernua was K (2n) = 2x = 16 = 10m + 2sm + 4st and P. tongkangensis was K (2n) = 2x = 16 = 10m + 4sm + 2st, respectively.

• Horticultural Science & Technology
• /
• v.33 no.6
• /
• pp.900-910
• /
• 2015

This study aimed to investigate the efficiency of colchicine and oryzalin in inducing polyploidy in two Cymbidium hybrids [Showgirl 'Silky' and Mystery Island 'Silk Road' (Silk Road-4)]. Colchicine was used at concentrations ranging from 50 to $500mg{\cdot}L^{-1}$, with treatments lasting 1 to 3 weeks. Oryzalin was used at concentrations ranging from 3 to $20mg{\cdot}L^{-1}$, with treatments lasting 3 to 6 days or 1 to 3 weeks. The survival rate of PLBs was better in colchicine than in oryzalin solutions. The ploidy levels were screened using flow cytometry. In C. Showgirl 'Silky', the highest chromosome doubling efficiencies were obtained with the 1-week treatment in $50mg{\cdot}L^{-1}$ colchicine (60%) and the 2-week treatment in $5mg{\cdot}L^{-1}$ oryzalin (46.7%). In C. Mystery Island 'Silk Road' (Silk Road-4), the highest chromosome doubling efficiencies were obtained with the 1-week treatment in $50mg{\cdot}L^{-1}$ colchicine (16.7%) and the 3-day treatment in $10mg{\cdot}L^{-1}$ oryzalin (6.7%). Colchicine was more efficient than oryzalin in terms of polyploidy induction. Furthermore, pre-treatment, which entailed poking 10 times with forceps, improved the efficiency of chromosome doubling.