• ALGAE
• /
• 제25권3호
• /
• pp.115-120
• /
• 2010

The natural growth of a population of Gomphosphaeria aponina Kutzing (Chroococcales, Cyanoprocaryota) was studied in a cemented freshwater tank in Allahabad, India. This population appeared to be a polymorphic species. Different species of the genus Gomphosphaeria have been segregated based on morphological features of colonies, cells and mucilage. However, these features are not well defined for different species. Our observations revealed many feature variations and, interestingly, certain features that have been described for different Gomphosphaeria species were seen in a single population. In this study, records of such variable morphological features were possible due to the availability of numerous specimens and continuous observations for more than two years. Further, this study revealed two points: (i) more detailed morphological studies are required both from nature as well as in culture to identify critical differences among the species, and (ii) molecular characterization of taxa appears to be necessary for final species settlement.

• Fisheries and Aquatic Sciences
• /
• 제17권4호
• /
• pp.461-469
• /
• 2014

Polychlorinated biphenyls (PCBs) are persistent pollutants in aquatic environments, often causing the decline or disappearance of wild populations. In this study, we used a random amplified polymorphic DNA (RAPD) assay to evaluate the effects on the genomic DNA of olive flounder embryo and larval stages of exposure to Aroclor 1254 at concentrations of 1, 5, 10, 20, and $40{\mu}g/L$. We compared RAPD fingerprints of exposed and non-exposed samples. Polymorphisms were revealed as the presence and/or absence of DNA fragments between the two samples. A dose-dependent increase in the number of polymorphic bands was observed with Aroclor 1254 treatment. Also, RAPD profiles of animals exposed to Aroclor 1254 exhibited an increase in the frequency values (FV) compared to the control. A phenogram constructed using neighbor-joining method indicated that genomic template stability in developing embryo and larval stages was significantly affected at ${\geq}5{\mu}g/L$. This study suggested that DNA polymorphisms detected by RAPD analysis could be used as an investigative tool for environmental toxicology and as a useful biomarker in early life stages for the detection of potential genotoxicants.

• 자원환경지질
• /
• 제19권1호
• /
• pp.57-66
• /
• 1986

The ore deposit of the Ohtani mine is one of representatives of plutonic tungsten-tin veins related genetically to acidic magmatism of Late Cretaceous in the Inner zone of Southwest Japan. Based on macrostructures of vein filling, three major mineralization stages are distinguished by major tectonic breaks. The constituents of ore minerals are scheelite, cassiterite, chalcopyrite, pyrrhotite, sphalerite, with small amounts of cubanite, stannite, galena, native bismuth, bismuthinite, arsenopyrite and pyrite. The relationship between the polymorphic variations of pyrrhotite and the kinds of the associated characteristic of ore mineral, in relation with hypogene mineralization, has been demonstrated. Pyrrhotite of stage I is predominantly of the hexagonal phase (Hpo>Mpo). Pyrrhotite of stage II is mainly of the monoclinic phase ($Hpo{\ll}Mpo$). Pyrrhotite of stage III is a single monoclinic phase ($Hpo{\ll}Mpo$). The compositions of the hexagonal pyrrhotite decrease in Fe content ranging from 47.44 atom % Fe in stage I to 46.88 atom % Fe in stage III.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제10권2호
• /
• pp.79-86
• /
• 2005

Molecular markers have increasingly been used in plant genetic analysis, due to their obvious advantages over conventional phenotypic markers, as they are highly polymorphic, more in number, stable across different developmental stages, neutral to selection and least influenced by environmental factors. Among the PCR based marker techniques, ISSR is one of the simplest and widely used techniques, which involves amplification of DNA segment present at an amplifiable distance in between two identical microsatellite repeat regions oriented in opposite direction. Though ISSR markers are dominant like RAPD, they are more stable and reproducible. Because of these properties ISSR markers have recently been found using extensively for finger printing, pohylogenetic analysis, population structure analysis, varietal/line identification, genetic mapping, marker-assisted selection, etc. In mulberry (Morus spp.), ISSR markers were used for analyzing phylogenetic relationship among cultivated varieties, between tropical and temperate mulberry, for solving the vexed problem of identifying taxonomic positions of genotypes, for identifying markers associated with leaf yield attributing characters. As ISSR markers are one of the cheapest and easiest marker systems with high efficiency in generating polymorphism among closely related varieties, they would play a major role in mulberry genome analysis in the future.

• 한국응용곤충학회지
• /
• 제53권4호
• /
• pp.355-365
• /
• 2014

배추좀나방(Plutella xylostella)이 국내에서 월동이 가능한 지 명확하지 않았다. 본 연구는 배추좀나방의 내한성에 기초한 야외 노출 실험을 실시하여 월동 환경 조건을 결정하고, 동계 야외 지역의 배추좀나방 유충 서식지 관찰 및 성페로몬을 이용한 성충 모니터링을 통해 월동이 가능한 지 조사하였다. 또한 이들 월동집단의 유래를 추적하기 위해 다형유전좌위를 이용한 집단 분석을 실시하였다. 배추좀나방의 체내빙결점 보다 높은 $-5^{\circ}C$로 처리한 결과 모든 미성숙 발육태에서 뚜렷한 생존력 저하를 보여 직접적 냉해 피해를 주었다. 여기서 유충발육태는 가장 낮은 냉해 피해를 받았다. 그러나 $5^{\circ}C$로 장기간(4 주) 처리한 결과 냉해 피해는 없었지만, 유충의 경우 먹이가 없는 상태에서 치사율이 증가했다. 모든 발육태의 배추좀나방을 대상으로 겨울 기간 동안 야외조건에 노출시킨 결과 모든 발육태에서 생존력 저하를 나타냈다. 그러나 비가온 실내조건에서 저온 피해를 줄였으며 유충의 경우 먹이가 공급되면 생존력이 뚜렷하게 증가하였다. 동계 성페로몬 모니터링 결과 2014년도 최초의 성충발생일은 유사한 시기에 서로 다른 지역(약 260 Km 거리)에서 나타났으며 월동집단의 성충은 4월 상순까지 포획되었다. 지역간 이들 월동집단의 유전적 거리는 다형분자마커를 이용하여 분석되었으며 이들 월동집단들 사이에 뚜렷한 유전적 분화가 있는 것을 나타냈다. 본 연구는 배추좀나방의 국내 월동이 남쪽 지역 또는 기주 식물이 있는 시설재배지에서 가능한 것으로 제시하고 있다.

• Animal cells and systems
• /
• 제13권2호
• /
• pp.179-186
• /
• 2009

Discriminating between eel species of the genus Anguilla using morphological characteristics can be problematic, particularly in the glass eel and elver stages. In this study, sequence-characterized amplified region (SCAR) and polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) markers were developed for the identification of Anguilla japoniea, Anguilla btcoior bicaor. Anguilla rostrata, and Anguilla anguilla. Random amplified polymorphic DNA (RAPD) fragments from A. japoniea (362 bp), A. bicolor bicctor (375 bp), A. rostrata (375 bp), and A. anguilla (375 bp) were isolated, sequenced, and converted to SCAR markers. The principal difference between the SCARs of A. japoniea and the three other species is the absence of a 13 bp deletion in the A. japoniea SCAR. Specific PCR primers amplified a 290 bp fragment for A. japoniea and 303 bp fragments for A. bicolor bicoior. A. rostrata, and A. anguilla. Restriction enzyme digestion with Taql, Mael, and Tru9l yielded PCR-RFLP patterns with differences that, when analyzed together, are sufficient for distinguishing each of the four eel species. In addition, RAPD fragments for A. japoniea (577 bp), A. bicoior bicoor (540 bp), A. rostrata (540 bp), and A. anguilla (509 bp) were also isolated and sequenced. The A. japoniea, A. bicoior blcoior. A. rostrata, and A. anguilla PCR products contain ten, nine, nine, and eight tandem repeats, respectively, of a 37 bp sequence. These results suggest that SCAR and PCR-RFLP markers and repeat numbers for specific loci will be useful for the identification of these four Anguilla eel species.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2022년도 추계학술대회
• /
• pp.191-191
• /
• 2022

Heterostyly continues to fascinate evolutionary biologists interested in heredity, evolution, breeding, and adaptive function. Polymorphism demonstrates how simply inherited developmental changes in the location of plant sexual associations can have important consequences for population pollination and mating biology. In contrast to homozygous self incompatibility, only a small number of mating phenotypes can be maintained in the population because insect pollinators have limitations in achieving multiple segregation sites for pollen deposition. Field studies of pollen tube growth have shown that reciprocal style-stamen polymorphisms function to increase the capacity of insect-mediated cross-pollination. The genetic pattern of style morphs is well established in various taxa, but despite recent advances, the identity, number, and structure of the genes controlling the heteromorphic syndrome have been poorly elucidated. The phenomenon of heterostyly in buckwheat has been controlled by gene complex concentrate to S-locus. Homomorphic autogamous buckwheat strains were established by the interspecific hybridization. Backcrossing of this line to the common buckwheat (pin) and selecting homostylar progenies made it possible to introduce the self-compatible gene into common buckwheat. In the result, we obtained the BC₉F₂ generation, and defined the strong linkage between flower type and self-incompatibility by microscopic observation of pollen tube growth. This finding suggests that self-incompatibility character is not controlled by one gene. Moreover, we defined the strong linkage between flower type and self-incompatibility. It strongly supports the S supergene theory. Therefore, we have plan to elucidate the heterostyly self-incompatibility by using molecular genetics, proteome analysis and apply to exploitation of buckwheat improvement. In near future, the expression of heterozygous syndromes in genus Fagopyrum with single isolated heterozygous species may provide clues to early stages of polymorphic assembly and shed light on evolutionary models of heterozygous strains.

• 한국어병학회지
• /
• 제18권1호
• /
• pp.19-28
• /
• 2005

2003년 북제주 지역의 육상양식장에서 양식중인 넙치에서 새로운 타입의 스쿠티카섬모충을 분리하였다. 이 충은 환경에 따라 ciliate와 cyst로 변태하며 장기간 생존하였는데, ciliate stage의 크기는 영양상태가 양호한 시기 기준 평균 길이 41.8, 폭 21.0 ${\mu}m$ 이었으며, cyst stage는 평균 길이 17.0 ${\mu}m$, 폭 13.5 ${\mu}m$ 이었다. 변태하는 주 원인은 먹이 양이었다. 먹이가 부족하면 cyst로 변태하여 장기간 생존이 가능하며, 먹이가 풍부해지면 ciliate로 재변태하여 활발히 증식하였다. In vitro 배양시험 결과 MS BHI 배지에서 비브리오균 (V. lentus)을 먹이로 하여 15$^{\circ}C$에서 최고 2.9${\times}$105 ${m\ell}^{-1}$의 고밀도로 배양되었다. 환경에 대한 적응시험 결과 ciliate는 염분농도 1-55 ppt, 온도 2.5-30$^{\circ}C$, pH 6-9 범위에서 증식이 가능하였다. 특히 0$^{\circ}C$에서도 7일 이상 장시간 생존이 가능하여 환경에 대한 적응력이 매우 뛰어났다. cyst는 먹이가 없는 상태에서 장시간 생존이 가능하였는데, 5$^{\circ}C$에서는 320일 동안 생존하였으며 온도가 높아질수록 생존기간은 짧아졌다. 화합물을 이용한 in vitro 구제시험에서는 포르말린과 과산화수소 모두 200 ppm/1시간 약욕으로 구제효과가 있었으나 화합물의 약욕농도와 시간에 따라 효과가 달랐다.

• 한국어병학회지
• /
• 제17권3호
• /
• pp.159-169
• /
• 2004

2003년 5월과 2003년 10월동안에 제주도내 5개소의 넙치 종묘배양장에서 초기 먹이로 공급 되어지는 동물성 플랑크톤인 rotifer와 20-30일령 넙치 자어에서 장관백탁증 원인균으로 알려진 V. ichthyoenteri를 분리하기 위해 실험한 결과 총 71개의 Vibrio sp. 분리가 되었고, 생화학적 동정결과 2개의 그룹에서 24개의 V ichthyoenteri가 동정 되었다. V. ichthyoenteri의 신속한 검출을 위한 종특이적 primer를 V. ichthyoenteri(KCCM 40870)ISR의 특이적인 서열을 이용하여 제작하였다. V. ichthyoenteri를 포함한 20종의 Vibrio속 균주의 genomic DNA와 18group 분리균주 genomic DNA를 PCR한 결과 V. ichthyoenteri 만의 특이적인 band가 생성됨을 알 수가 있다. 따라서 V. ichthyoenteri(KCCM 40870) ISR의 서열로 제작한 primer가 넙치 자치어에 발병하는 장관백탁증 원인균인 Vibrio ichthyoenteri의 신속한 검출과 정확한 동정을 할 수 있는 molecular marker로 이용할 수 있음을 확인하였다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권6호
• /
• pp.2629-2633
• /
• 2012

Background: Raw betel nut (RBN) chewing is an important contributing factor for esophageal squamous cell carcinoma (ESCC), although associated genomic changes remain unclear. One difficulty in assessing the effects of exclusively RBN induced genetic alterations has been that earlier studies were performed with samples of patients commonly using tobacco and alcohol, in addition to betel-quid. Both CDKN2A (at 9p21) and Rb1 gene (at 13q14.2) are regarded as tumor suppressors involved in the development of ESCC. Therefore, the present study aimed to verify the RBN's ability to induce ESCC and assess the involvement of CDKN2A and Rb1 genes. Methods: A panel of dinucelotide polymorphic markers were chosen for loss of heterozygosity studies in 93 samples of which 34 were collected from patients with only RBN-chewing habit. Promoter hypermethylation was also investigated. Results: Loss in microsatellite markers D9S1748 and D9S1749, located close to exon $1{\beta}$ of CDKN2A/ARF gene at 9p21, was noted in 40% ESCC samples with the habit of RBN-chewing alone. Involvement of a novel site in the 9p23 region was also observed. Promoter hypermethylation of CDKN2A gene in the samples with the habit of only RBN-chewing alone was significantly higher (p=0.01) than Rb1 gene, also from the samples having the habit of use both RBN and tobacco (p=0.047). Conclusions: The data indicate that the disruption of 9p21 where CDKN2A gene resides, is the most frequent critical genetic event in RBN-associated carcinogenesis. The involvement of 9p23 as well as 13q14.2 could be required in later stages in RBN-mediated carcinogenesis.