• Asian-Australasian Journal of Animal Sciences
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• 제22권1호
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• pp.1-6
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• 2009

Genetic variability is an important component in the ability of populations to adapt in the face of environmental change. Severe human impacts reduced Muzzafarnagri sheep of India from 500,000 in 1972 to 10,989 in 1973-74. Here we report for the first time the effect of this population decline on levels of genetic variability at 13 FAO recommended ovine microsatellite loci and contrast levels of variability to that in a breed from the same geographical region, which differed in numbers, by an order of magnitude (Marwari sheep). Of the 13 loci, 100% were polymorphic in both breeds. A high degree of genetic variation was observed within populations in terms of both allele diversity (number of alleles per locus, >4) and gene diversity (expected heterozygosity, >0.5), which implied that there is still a substantial amount of genetic diversity at the nuclear loci in a declining population. Nevertheless, overall low number of alleles per locus and relatively less abundance of low frequency alleles in Muzzafarnagri sheep suggested that genetic variability has been comparatively reduced in this population. Bottleneck analysis indicated that a genetic bottleneck did not occur during the most recent decline. In addition, we found that the differentiation among populations was moderate ($F_{ST}$= 11.8%). This study on assessment of genetic effects of the population declines in ovines is a step towards identification of genetically impoverished or healthy populations, which could prove to be a useful tool to facilitate conservation planning in this important species of small ruminants.

• Journal of Species Research
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• 제7권4호
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• pp.354-362
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• 2018

Population genetic assessment is essential for the conservation and management of endangered and rare plants. Neofinetia falcata is endangered epiphyte orchid and protected by law in Korea. In Korea, this species is only found on islands in the South Sea of Korea (including Jeju-do) and the southern coast of the Korean Peninsula. We developed nine microsatellite makers to assess the genetic diversity and population genetic structure of three populations of N. falcata. The genetic diversity at the species level was low, which can be attributed to inbreeding or fragmentation into small, isolated populations. A recent bottleneck was detected in one population, likely due to overcollection. N. falcata exhibited moderated levels of differentiation among populations, with the three populations were divided into two clusters based on genetic structure. The genetic diversity and structure of N. falcata are affected by restricted gene flow by pollen or seeds due to isolation and geographic distance. Strategies for in situ and ex situ conservation of this species are been proposed based on the results of our study.

• 식물분류학회지
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• 제43권4호
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• pp.245-251
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• 2013

작약은 원예 및 전통한약으로 중요한 자연자원이다. 경주국립공원 일대에서 발견된 야생 작약 집단에 대한 보전 및 활용 방안 마련을 위해 마이크로새틀라이트 마커를 활용한 유전적 다양성 분석을 수행하였다. 경주국립공원 일대 3개 집단과 중국 연변 1개 집단 등 4개 집단을 대상으로 유전적 다양성 분석을 수행한 결과, 5개의 마이크로새틀라이트 마커로부터 61개의 대립유전자를 확인하였으며, 평균 이형접합성($H_o$)은 0.452로 나타났다. 집단 간의 유전적 분화는 $F_{ST}$=0.116로 볼 때 비교적 낮은 수준인 것으로 나타났으며, 계층적 AMOVA 분석 결과 유전적 변이가 집단 간보다는 집단 내 개체사이에 분포하는 것으로 확인되었다. 그러나 $F_{ST}$값 대신 대립유전자의 크기를 고려한 $R_{ST}$ 값을 사용한 AMOVA 분석 결과에서는 중국 집단과 국내 집단 사이에 두드러진 차이가 나타났다. 이러한 양상은 STRUCTURE 분석에서도 확인되었다. 한편, 경주국립공원 일대 3개 집단 사이에는 지속적인 유전자 흐름이 일어나고 있는 것으로 확인되었으며, 작은 집단 크기와 성숙한 개체가 적은 것으로 볼 때, 추가적인 보호 및 장기 모니터링이 필요할 것으로 판단된다.

• Journal of Genetic Medicine
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• 제9권2호
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• pp.67-72
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• 2012

The generation of induced pluripotent stem cells (iPSCs) derived from patients' somatic cells provides a new paradigm for studying human genetic diseases. Human iPSCs which have similar properties of human embryonic stem cells (hESCs) provide a powerful platform to recapitulate the disease-specific cell types by using various differentiation techniques. This promising technology has being realized the possibility to explore pathophysiology of many human genetic diseases at the molecular and cellular levels. Furthermore, disease-specific human iPSCs can also be used for patient-based drug screening and new drug discovery at the stage of the pre-clinical test in vitro. In this review, we summarized the concept and history of cellular reprogramming or iPSC generation and highlight recent progresses for disease modeling using patient-specific iPSCs.

• 한국잠사곤충학회지
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• 제39권2호
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• pp.119-133
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• 1997

Isozyme was used to characterize general protein patterns of genetic relationships among 303 silkworm stocks preserved in National Sericultural and Entomology Research Institute, RDA. Six isozymes (esterase, acid phosphatase, alkaline phosphatase, amylase, glucose-6-phosphate dehydrogenase and sucrase) from hemolymph, midgut, and digestive juice were employed to construct dendograms(UPGMA method) using a polycrylamide gel electrophoresis. A cluster analysis revealed four major group, which were divided into several subgroups within each group, contained assemglages of Japanese and Chinese races. Especially, genetic differentiation in the first and second group was greatest rather than within Japanese and Chinese races repectively and was concordant with the hypothesis of phyletic sorting of initial variability in China many years ago. Hypothesized recent introgression between groups was also plausible, but the eviednce suggested bidirectional gene flow between the Chinese and the Japnaese lineages. Interpreting the results in light of evidence from the current study, the genetic diversity and relationship showed in Korean silkworm race, Hansammyun reflected early and independent evolution from the Chinese ancestor, limited addition of new variability and phyletic sorting within Korean peninsula more than 4,000 years.

• Journal of Plant Biology
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• 제37권3호
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• pp.277-284
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• 1994

I investigated levels of genetic diversity, population genetic structure, and gene flow in Hostacapitata, a herbaceous perennial native to South Korea and southwestern Japan. Starch gel electrophoresis was conducted on leaves collected from 310 plants in 19 Korean populations. Twenty-two of 25 putative loci examined were polymorphic in at least one populatin and the mean number of alleles per locus was 1.65. In addition, mean expected heterozygosity within populations (Hep=0.153) was higher than average values for species with similar life history traits. Significant differences in allele frequency were detected between populations at all loci (P<0.01), and slightly over 30% of the genetic variation was found among populatins (GST=0.308). Indirect estimates of the number of migrants per generation (Nm) (0.506, calculated from GST; 0.852, calculated from the mean frequency of ten private alleles) indicate that gene flow is restricted among the isolated Korean populations of H. capitata. Factors contributing to the high levels of genetic differentiation among populations of H. capitata include small and discrete populations, human disturbance, and low frequencies of pollinator foraging behavior.

• Animal cells and systems
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• 제3권2호
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• pp.207-213
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• 1999

During the differentiation of Naegleria gruberi amoebas into flagellates, the amoebas undergo sequential changes in cell shape and form new cellular organelles. To understand the nature of the signal which initiates this differentiation and the signal transduction pathway, we treated cells with four agents, PMA, retinoic acid (RA), okadaic acid, and cAMP. Retinoic acid and cAMP had specific effects on the differentiation of N. gruberi depending on the time of the drug treatment. Addition of (100$\mu$M) retinoic acid at the initiation of differentiation inhibited differentiation by blockinq the transcription of differentiation specific genes (e.g., $\beta$-tubulin). This inhibition of differentiation by retinoic acid was overcome by co-treatment with cAMP (or dbcAMP, 20 $\mu$M). Addition of retinoic acid at later stages (30 and 70 min) had no effect on the transcriptional regulation of the $\beta$-tubulin gene, however the differentiation was inhibited by different degrees. Co-treatment of cAMP at these stages did not overcome the inhibitory effect of retinoic acid. These results suggest that the role of retinoic acid as a transcriptional regulator might be conserved throughout the evolution of eukaryotes.

• 한국자원식물학회지
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• 제24권6호
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• pp.702-711
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• 2011

Buckwheat (Fagopyrum esculentum Moench), one of the minor crops grown in Korea belonging to the Polygonaceae family, is an annual crop widely cultivated in Asia, Europe, and America and has a character of outcrossing and self-incompatibility. The objective of this study was to analyze the genetic variability, phylogenetic relationships and population structure of buckwheat landraces of Korea using SSR markers. Ten microsatellite markers have been detected from a total of 79 alleles among the 179 buckwheat accessions were collected from Korea. The number of allele per marker locus ($N_A$) ranged from 2 (GB-FE-001, GB-FE-043 and GB-FE-055) to 31 (GB-FE-035) with an average of 7.9 alleles. GB-FE-035 was the most polymorphic with the highest PIC value 0.93. Major allele frequencies ($M_{AF}$) for the 10 polymorphic loci varied from 0.12 to 0.97 with a mean allele frequency of 0.57. The expected heterozygosity ($H_E$) values ranged from 0.05 to 0.94 with an average of 0.53. The observed heterozygosity ($H_O$) ranged from 0.06 to 0.92 with an average of 0.42. The overall polymorphic information contents (PIC) values ranged from 0.05 to 0.93 with an average of 0.48. The landrace accessions of buckwheat used in the present study were not distinctly grouped according to geographic distribution. The study concludes that the results revealed genetic differentiation was low according to the geographic region because of outcrossing and self-incompatibility. We reported that our analyses on the genetic diversity of common buckwheat cultivars of Korea were performed by using of microsatellite markers.

• Journal of Ginseng Research
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• 제41권3호
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• pp.298-306
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• 2017

Background: Compound K (CK) is a bioactive derivative of ginsenoside Rb1 in Panax ginseng (Korean ginseng). Its biological and pharmacological activities have been studied in various disease conditions, although its immunomodulatory role in innate immunity mediated by monocytes/macrophages has been poorly understood. In this study, we aimed to elucidate the regulatory role of CK on cellular events mediated by monocytes and macrophages in innate immune responses. Methods: The immunomodulatory role of CK was explored by various immunoassays including cell-cell adhesion, fibronectin adhesion, cell migration, phagocytic uptake, costimulatory molecules, reactive oxygen species production, luciferase activity, and by the measurement of mRNA levels of proinflammatory genes. Results: Compound K induced cell cluster formation through cell-cell adhesion, cell migration, and phagocytic activity, but it suppressed cell-tissue interactions in U937 and RAW264.7 cells. Compound K also upregulated the surface expression of the cell adhesion molecule cluster of differentiation (CD) 43 (CD43) and costimulatory molecules CD69, CD80, and CD86, but it downregulated the expression of monocyte differentiation marker CD82 in RAW264.7 cells. Moreover, CK induced the release of reactive oxygen species and induced messenger RNA expression of proinflammatory genes, inducible nitric oxide synthase, and tumor necrosis factor-alpha by enhancing the nuclear translocation and transcriptional activities of nuclear factor kappa-B and activator protein-1. Conclusion: Our results suggest that CK has an immunomodulatory role in innate immune responses through regulating various cellular events mediated by monocytes and macrophages.

• Journal of Animal Science and Technology
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• 제46권1호
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• pp.15-22
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• 2004

제주마의 세 구룹의 집단(group I , 제주도축산진홍원 관리마; group Il , 농가사육마; group III, 제주경마장의 경주마)과 외래품종인 Thoroughbred, Mongolian horse 및 Quarter horse에 있어서 transfemin 유전자 분포를 비교하기 위하여 Transferrin 유전자 exon 13, 15 및 16에 대하여 SSCP 분석을 수행하였다. 조사된 유전자의 빈도는 집단간의 유전적 분화거리를 측정하는데 이용되었고 집단분화의 유의성을 검정하였다. 집단분화를 나타내는 Fst 값에 의하면 제주마 group I 은 group Il (0.067) 및 group III(0.070)와는 가깝게 위치하고 있었으나 Mongol 집단과는 0.091 로， Thoroughbred 집단과는 0.189의 유전적으로 거리가 다소 먼 분화된 집단관계를 보여주고 있었다. 또한 제주마 group I 은 외래품종인 Thoroughbred, Mongolian horse, American Quarter 집단뿐만 아니라 제주마 group Il 및 m와도 차별화 되는 집단으로 유지되고 있음을 보여주고 있었다'(p <0.05). 제주 경마장에 경주마로 이용되고 있는 제주마 group ill는 제주마 group I 및 Thoroughbred 품종집단에 대해서 칩단분화에 유의성이 안정 ( p < 0.01)되 었고 나머지 다른 집단과는 집단분화의 유의성이 없었다(p > 0.05). 제주마 group Il, group Ill 및 몽고마 사이에는 분화 확률의 유의성이 없어서 이들 집단간에는 유전자 빈도가 매우 유사한 것으로 생각되었다. 이로서 비교적 짧은 기간에 번식환경의 격려 또는 외래품종의 유전자 유업에 의하여 제주마의 transferrin 유전자 빈도는 제주마 집단간에 이질화를 초래하고 있으며， 집단의 분화가 유전자의 유엽이 원인이라면 혈통보존되는 축산 진홍원의 관리집단 이외의 제주마 집단은 외래 품종의 유전자 유업으로 제주마의 고유한 유전적 특성이 빠른 속도로 희석될 것으로 생각된다.