• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.1017-1025
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• 2006

Hantaviruses possess three RNA segments of negative sense. Co-infection of closely related hantaviruses may result in generation of a progeny virus with genomic polyploidy, containing a partial or complete set of genome originated from more than one parental virus. To characterize the formation of viral genomic polyploidy, cultured Vero-E6 cells were co-infected with two closely related hantaviruses, Hantaan and Maaji, and the progeny viruses examined. The genotype of plaque-purified viruses was analyzed by a virus-specific RT-PCR. Seventy percent (67/96) of the progeny virus was categorized as Hantaan and 3.3% (2/96) was classified as Maaji, whereas 20% (21/96) was considered polyploidy as they contained both types of the S RNA segment. Most of the polyploidy progeny viruses were unstable and gave rise to either one of the parental viruses or a reassortant after several rounds of plaque purification. No recombination between the heterologous pair of S RNA was observed for those polyploid viruses during three consecutive plaque-to-plaque passages. These data suggest that the viral polyploidy formation constitutes a primary mechanism underlying the generation of a newly emerged hantavirus.

• 한국발생생물학회지:발생과생식
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• 제21권4호
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• pp.425-434
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• 2017

Polyploidy is occurred by the process of endomitosis or cell fusion and usually represent terminally differentiated stage. Their effects on the developmental process were mainly investigated in the amphibian and fishes, and only observed in some rodents as mammalian model. Recently, we have established tetraploidy somatic cell nuclear transfer-derived human embryonic stem cells (SCNT-hESCs) and examined whether it could be available as a research model for the polyploidy cells existed in the human tissues. Two tetraploid hESC lines were artificially acquired by reintroduction of remained 1st polar body during the establishment of SCNT-hESC using MII oocytes obtained from female donors and dermal fibroblasts (DFB) from a 35-year-old adult male. These tetraploid SCNT-hESC lines (CHA-NT1 and CHA-NT3) were identified by the cytogenetic genotyping (91, XXXY,-6, t[2:6] / 92,XXXY,-12,+20) and have shown of indefinite proliferation, but slow speed when compared to euploid SCNT-hESCs. Using the eight Short Tendem Repeat (STR) markers, it was confirmed that both CHA-NT1 and CHA-NT3 lines contain both nuclear and oocyte donor genotypes. These hESCs expressed pluripotency markers and their embryoid bodies (EB) also expressed markers of the three embryonic germ layers and formed teratoma after transplantation into immune deficient mice. This study showed that tetraploidy does not affect the activities of proliferation and differentiation in SCNT-hESC. Therefore, tetraploid hESC lines established after SCNT procedure could be differentiated into various types of cells and could be an useful model for the study of the polyploidy cells in the tissues.

• 식물분류학회지
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• 제41권3호
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• pp.215-222
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• 2011

Various aneuploidy and polyploidy have been reported in the genus Aconitum L. (ca. 300 species worldwide, Ranunculaceae), and there is a demonstrated association between major lineage diversification and polyploidy. This study reports chromosome counts of eight Aconitum from Korea, including the first counts for A. japonicum Thunb. subsp. napiforme ($H. L{\acute{e}}v.$ & Vaniot) Kadota (2n = 32) and A. longecassidatum Nakai (2n = 16). The study also includes chromosome numbers for two taxa on the Critically Endangered species list in Korea. Among Korean native species, chromosome numbers in Aconitum subgenus Aconitum range from 2n = 16 to 2n = 64 with diverse levels of polyploidy (2x, 4x, and 8x), whereas Aconitum subg. Lycoctonum exhibits only diploids (2n = 16). Greater chromosome number diversity in subg. Aconitum than subg. Lycoctonum might explain higher species diversity within the former subgenus (more than 250 species worldwide). Investigating chromosome number diversity of Aconitum in a phylogenetic framework will be a critical step to understand species richness of the genus.

• Biomolecules & Therapeutics
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• 제30권5호
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• pp.391-398
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• 2022

Polyploidization is a process by which cells are induced to possess more than two sets of chromosomes. Although polyploidization is not frequent in mammals, it is closely associated with development and differentiation of specific tissues and organs. The liver is one of the mammalian organs that displays ploidy dynamics in physiological homeostasis during its development. The ratio of polyploid hepatocytes increases significantly in response to hepatic injury from aging, viral infection, iron overload, surgical resection, or metabolic overload, such as that from non-alcoholic fatty liver diseases (NAFLDs). One of the unique features of NAFLD is the marked heterogeneity of hepatocyte nuclear size, which is strongly associated with an adverse liver-related outcome, such as hepatocellular carcinoma, liver transplantation, and liver-related death. Thus, hepatic polyploidization has been suggested as a potential driver in the progression of NAFLDs that are involved in the control of the multiple pathogenicity of the diseases. However, the importance of polyploidy in diverse pathophysiological contexts remains elusive. Recently, several studies reported successful improvement of symptoms of NAFLDs by reducing pathological polyploidy or by controlling cell cycle progression in animal models, suggesting that better understanding the mechanisms of pathological hepatic polyploidy may provide insights into the treatment of hepatic disorders.

• 한국가축번식학회지
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• 제20권4호
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• pp.379-384
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• 1997

외인성 성선자극 호르몬에 의한 과배란처리는 난모세포의 질, 수정, 배발달, 착상, 임신유지 등에 해로운 영향을 수반하는 광범위한 배란전후의 호르몬 분비이상을 야기한다. 최근 본 연구에서 흰쥐에서의 IGF-1이 착상전 및 자궁의 환경적 조절에 미치는 잠재적 역할을 확인하였다. 그 결과는 IGF-1이 아마도 탈락막의 조절과 배발달에 적합한 자궁환경유지에 중요한 역할을 수행한다는 것을 보여주었다. 과배란후 배의 손실과 착상의 실패는, 본 연구에서 관찰되었듯이 부분적인 자궁내 IGF-1의 작용저해에 기인하리라 사료된다. 또한 본 연구진들은 생쥐의 배에서 염색체 이상빈도에 대한 과배란을 유도하는 성선자극 호르몬의 영향에 대한 연구를 수행하였다. PMSG 5, 10 및 15 I.U.를 투여하여 과배란된 생쥐에서 생쥐의 수정란과 8-16 세포기 배의 염색체 분석을 실시하였다. 이수체(aneuploidy), 다배체(polyploidy) 또한 염색체의 구조적 이상은 4개군에서 관찰되었따. 그러나 다배체만이 과배란과 상관관계가 있엇따. PMSG 10, 15 I.U. 처리군에서 다배체 발생율은 각각 2.9%와 10.5%였다. 더욱이 PMSG 용량에 따른 배의 다배체 발생빈도 사이에는 투여량에 따른 상관관계가 확인되었다(P<0.0001). 과배란과 성선자극호르몬은 양의 상관관계가 있었으며 염색체와 과배란의 정도에는 투여량에 따른 상관관계가 있었다. 과배란된 난모세포의 발달 잠재력은 모축의 내분비적 환경뿐만 아니라 생존에 필요한 내인성 요인들 즉 유전적 상태 그리고 난자의 전체적 성숙등에 연관되어 있다고 사료된다.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2006년도 수산관련학회 공동학술대회 발표요지집
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• pp.627-628
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• 2006

• 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.

• 농업과학연구
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• 제38권1호
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• pp.7-10
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• 2011

In order to develop the new Miscanthus varieties for biomass, characteristics of collected materials were surveyed. Also, they were treated with S-azide(Sodium-azide) and DES(dethyl sulfate) for promising lines and 0.2% Colchicine for polyploidy, respectively. CNU-J1 line induced with chemical, DES and S-azide treatment showed shorter than others in stem height and stem diameter. CNU-N1 line treated with 10 mM DES showed earlier than non-treated lines in flowering as 7days. Among selected lines, the CNU-J1 line was crossed with DB-1 selected as a superior line and their hybrid was expected to be high in biomass than others. Especially, CNU-W1 line treated with 2.5~5.0 mM DES showed heading in M1 generation.

• BMB Reports
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• 제39권5호
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• pp.607-617
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• 2006

A novel calcium-dependent protein kinase gene (designated as IiCPK2) was cloned from tetraploid Isatis indigotica. The full-length cDNA of IiCPK2 was 2585 bp long with an open reading frame (ORF) of 1878 bp encoding a polypeptide of 625 amino acid residues. The predicted IiCPK2 polypeptide included three domains: a kinase domain, a junction domain (or autoinhibitory region), and a C-terminal calmodulin-like domain (or calcium-binding domain), which presented a typical structure of plant CDPKs. Further analysis of IiCPK2 genomic DNA revealed that it contained 7 exons, 6 introns and the length of most exons was highly conserved. Semi-quantitative RT-PCR revealed that the expression of IiCPK2 in root, stem and leaf were much higher in tetraploid sample than that in diploid progenitor. Further expression analysis revealed that gibberellin ($GA_3$), NaCl and cold treatments could up-regulate the IiCPK2 transcription. All our findings suggest that IiCPK2 might participate in the cold, high salinity and GA3 responsive pathways.

• 한국잠사곤충학회지
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• 제36권2호
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• pp.97-101
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• 1994

자연교잡으로 결실한 2배, 3배, 4배 및 6배체 뽕나무로 부터 채종한 종자의 형태임성 및 발아력은 다음과 같다. 1. 종자의 크기는 4배성 뽕나무의 종자가 가장 크고 2배성의 것은 약간 크며 3배성의 것은 보통 크기이고 6배성의 것은 극히 작았다. 2. 3배성뽕나무 가운데 신광뽕의 임실율은 25.4%이고 교잡성공율은 10.2% 이었으며, 청운뽕 55%의 임실율을 나타냈지만 발아력이 전무하였다. 3. 4배성뽕나무의 종자는 약 61~98%의 임실율을 나타내고 교잡성공율은 약 30~54%이었으며 6배성인 북산2호는 약 43%의 임실율, 7%의 교잡성공율을 나타냈다. 4. 물에 뜨는 종자의 발아력은 2배 및 4배체의 종자는 상당한 수준이었으나 3배 및 6배체의 것은 발아력이 없었다. 5. 2배성 뽕나무의 임실율은 약 81~95%의 고임성이고 교잡성공율도 약 47~74%로서 비교적 높았다.