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        검색결과 236

        181.
        2017.10 KCI 등재 서비스 종료(열람 제한)
        The Purpose of this study is investigated to education program and organization in Korea agricultural extension service center. In most cases, the program has steadily operated from 2014 to 2016 in metropolitan cities, specially, In Busan, the greatest education program has been set up twenty one classes during 2014~2016. This study surveyed 114 departments of 3 Agricultural Research & Extension Services and 75 Agricultural Technology Centers in 8 metropolitan cities, 9 provinces and 67 cities and counties, which implemented the consumer horticultural education programs in 2016. Twenty one agricultural extension service centers has started the consumer horticulture program undertaking for the first time in 2016. Experienced education program had been conducted to the facilities for the consumer horticulture programs in the agricultural extension service centers and training in the educational farm. Specially The Seoul Metropolitan Government had the largest educational training center in 53.136 m2, with the largest educational farm in Gangwon-do province and the most popular crops were fruit. The research suggested that the consumer horticultural of educational practice and the short & long term of improvement efforts of latent educational curriculum. Agricultural Technology Centers had lands and facilities for exiting agricultural education and the environment to use nearby farms as education farms by establishing a network. Furthermore reconsidering is needed to improve the content, a systematic study of educational practice reformation plan to improve the quality of educational practice.
        182.
        2017.06 KCI 등재 서비스 종료(열람 제한)
        This study was conducted with the aim of evaluating the antibiotic effects of leaves, stems, and roots in yacon (Smallanthus sonchifolius). Antibacterial activity of leaf extract by disk diffusion method with Bacillus subtilis and Escherichia coli respectively showed 13.3 and 13.75mm diameters of clear zone. There was no significant difference between the stems and leaves. The minimum inhibitory concentration of leaves’ heating and agitation extraction showed a restrain of strain at 1mg/ml, but the stems and root extract did not appear. Yacon is a functional antibacterial material, and methanol extraction is more effective than water. This research was to investigate the growth stage of collection has the most effective antibacterial effects. It has collected yacon's leaves from June to October, which is an appropriate time for collection right before reaping. Yacon leaf has antibacterial effects on Bacillus subtilis, Escherichia coli, Enterococcus faecium, and Salmonella enteritifis. There were no significant differences by the growth stage of collection. Leaves collected in July are high in phenol which helps in sulfating activity works well considering the high scavenging capability of DPPH. Leaves collected in September are high in total flavonoid.
        183.
        2017.05 서비스 종료(열람 제한)
        Background : The practice of keeping the medicinal herbs at room temperature causes many problems, but due to lack of sufficient field research and study, it is difficult to improve related regulations and safety management. Methods and Results : The Cnidium Rhizome and Angelica gigas Root were inoculated with Lasioderma serricorne F. and incubated at 28℃ for 2.5 months and 5 months. After five months, the number of Lasioderma serricorne F. in Cnidium Rhizome increased from 30 to 1,429 (about 47 times). In the same period, the number of insects in Angelica gigas Root increased from 30 to 663 (about 22 times). Due to the rapid increase in pest population, hygiene deteriorated, changes in the active ingredient and appearance quality of the herbal medicines, which greatly damaged the value of the herbal medicine. Conclusions : These results show that current regulation requiring only sealing and not specifying the storage temperature do not guarantee quality safety. Therefore, it is necessary to establish appropriate preservation standards and improve management regulations in order to preserve safety.
        184.
        2017.05 서비스 종료(열람 제한)
        Background : Methicillin-Resistant Staphylococcus aureus (MRSA) is a multidrug-resistant (MDR) strain. Especially, MRSA is developing resistance to available antibacterial agents and causing complications in the treatment of infections related to skin, soft tissue, respiratory, bone, joint, and endovascular disorders. Therefore, antibacterial agent combination therapy appears to be a useful option, particularly in developing countries where antibiotic availability is limited. (+)-Usnic acid (UA) is uniquely found in lichens, and is especially abundant in genera such as Usnea and Cladonia. UA has antimicrobial activity against human and plant pathogens. Therefore, UA may be a good antibacterial drug candidate for clinical development. Methods and Results : In search of a natural products capable of inhibiting this multidrug-resistant bacteria, we have investigated the antimicrobial activity of UA against MRSA. In this study, the effects of a combination of UA and permeable agents against MRSA were investigated. For the measurement of cell wall permeability, UA with concentration of Ethylenediaminetetraacetic acid (EDTA) was used. In the other hand, Sodium azide (NaN3) was used as inhibitors of ATPase. These results suggest that the antibacterial effect of UA was potentiated by membrane-binding agents and ABC transporter-inhibiting agents, implying that antibacterial activity is associated with damage of the cell wall and inhibition of ATPase function by UA. Conclusion : UA and in combination with EDTA and NaN3 could lead to the development of new combination antibiotics against MRSA infection. The results of this study appear to be promising, and they are expected to enhance the use of natural products as drugs.
        185.
        2017.05 서비스 종료(열람 제한)
        Background : Cynanchum wilfordi is a typical myocardial medicinal crop. Because it penetrates more than 1m, it requires a lot of labor and harvesting costs. In addition, we needed 4 - 5 times of weeding until July, and in the soil with poor drainage, root rot disease occurs and yield is greatly reduced. Therefore, this study was conducted to develop new cultivation technology that can minimize the effort cost and increase the yield. Methods and Results : As a test material, container standards were used plume tube of diameter 30 ㎝ × height 50 ㎝, 80 ㎝, 100 ㎝. The culture soil manufactured by mixing cokofit 60%, peatmoss 10%, pearlite 6%, vermiculite 10%, zeolite 5%, and charcoal 5%. The compost was made by mixing fowl droppings 45% and cattle manure 5%. The mixing ratio of the culture soil and the compost was 100 : 0, 90 : 10, 80 : 20, 70 : 30, respectively, and the mixture was filled in the container. Cynanchum wilfordi seedling sow raising seedlings during one month seeds become dormancy breaking. Culture soil and container of Cynanchum wilfordi was effective 87% increase (384 ㎏/10 a → 720) in quantity contrast conventional culture in height 50 ㎝ container + culture soil 100 : 0. 80 and 100 ㎝ containers were found to be unsuitable for production throughout the year because of thin thickness of subterranean part and low commercial yield due to the long time required for roots to reach the hardpan layer. The yields of compost mixture decreased from 0% (720 ㎏/10 a) > 10% (642) > 20% (560) > 30% (475) in 50 ㎝ containers. When the compost content was more than 20%, the yield decreased due to physiological damage during the early growth. Conclusion : The culture soil and container cultivate for harvesting ease of Cynanchum wilfordi was effective saving more than 15 times more than the harvest time contrast manpower harvest and the yield was increased by 87%. Also, container cultivation was effective the cost cutting of installation dismantlement and redres since no need to move the cultivation area.
        186.
        2016.10 서비스 종료(열람 제한)
        Background : Ixeris genus has been used in traditional medicines as stomachics, sedatives, and diuretics. Ixeris dentata var albiflora is a kind of perennial herbaceous plant and one of the plants of the genus Ixeris (Asteraceae). It is well-known for edible wild vegetable in Korea, China, Japan, and Mongolia. Specially, Korean has its root and young leaf with appetizing vegetable due to bitter taste. Methods and Results : We isolated 8 genes that are involved in carotenoid biosynthesis using the Illumina/Solexa HiSeq2000 platform. In this study, a full-length cDNA clone encoding phytoene synthase (IdPSY), phytoene desaturase (IdPDS), ξ-carotene desaturase (IdZDS), lycopene β-cyclase (IdLCYB), and zeaxanthin epoxidase (IdZEP) and partial-length cDNA clones encoding lycopene ε-cyclase (IdLCYE), ε-ring carotene hydroxylase (IdCHXE), and β-ring carotene hydroxylase (IdCHXB2) were identified in I. dentata. The theoretical molecular weight (MW) and isoelectric point values of 8 genes were investigated. Sequence analyses revealed that these proteins shared high identity and conserved domains with their orthologous genes. IdPSY, IdPDS, IdZDS, IdLCYB, IdCHXB2, and IdZEP were constitutively expressed in the roots, stems, leaves, and flowers of I. dentata. Conclusion : Our study on the biosynthesis of carotenoids in I. dentata will provide basic data for elucidating the contribution of carotenoids to the considerable medicinal properties of I. dentata.
        187.
        2016.10 서비스 종료(열람 제한)
        Background : Schisandra chinensis is being weighted difficulties in stable production, there is increasing drought damage caused by climate change as shallow rooted crops. Therefore, the study was performed for water supply capacity and growth characteristics analysis by setting the irrigation method for the drought damage reduction. Methods and Results : Test material was used sophomore V-shaped planting Schisandra chinensis. Irrigation method were surface watering, underground watering, sprinkler and untreated. Underground irrigation was irrigation that buried hose and then dug up the 15㎝. Soil moisture tension was the irrigation after fixed at -30 ㎪(23%). Irrigation timing was performed in June-July that high drought damage and made the most fruit enlargement. The main investigating items were investigated fruit growth, normal fault rate, soil moisture and EC content according to the irrigation method. Normal fruit rate according to irrigation method were appeared in sprinkler(81, 74 %)>underground irrigation(76, 69 %)>surface irrigation(76, 67%)>untreated(66, 52 %). Cluster length of yield component was determined to effective irrigation method in fruit growth the highest in sprinkler. Soil moisture contents was maintained at appropriate level with significant -30㎪(23 %) in the sprinkler. EC content low with a downward trend in underground irrigation and sprinkler. Water supply capacity according to Irrigation Method were sprinkler 40 tons, underground irrigation 85 tons, surface irrigation 138 tons. Conclusion : Appropriate watering methods for drought damage reduction of Schisandra chinensis caused by climate change was determined in the most efficient irrigation method in sprinkler that high fruit growth and normal fruit rate, lower the required of water supply capacity.
        188.
        2016.05 서비스 종료(열람 제한)
        Background : For increasing saponin content of ginseng cultivated in shaded plastic house, this study was performed to investigate growth characteristics and saponin content of ginseng (Panax ginseng C.A. Mayer) according to foliar spray of germanium and water-soluble silicates processing. Methods and Results : Used a native species in this study is violet-stem variant that most commonly cultivated in ginseng’s farms. 1-year-old violet-stem variant was transplanted on March 24, 2015 and planting distance was 11 × 20 cm. Shading material of plastic house was used blue-white shading vinyl. The processing method of inorganic dissolved matter is as follows, we were diluted with germanium and water-soluble silicates to 500-fold, 1000-fold and investigated after foliar spray twice a month from May to September. The growth characteristics in above-ground part of 2-year-old ginseng was a good in the inorganic matters treatment compared to the control treatment, the difference of above-ground growth characteristics between the inorganic dissolved matters treatments was not significant. The growth characteristics in under-ground part of 2-year-old ginseng was a good in the inorganic matter treatments and root weight per plant in the 500-fold dilution of germanium was 12.4 g that increased by 29 % compared to the control (9.6 g). Crude saponin content of under-ground part was higher generally in inorganic matter treatments compared to the control (11.53 ㎎/g). In the 1000-fold dilution of water-soluble silicate and germanium (50:50), crude saponin content was the highest in 12.91 ㎎/g. Crude saponin content of above-ground part was higher generally in inorganic matter treatments compared to the control (61.76 ㎎/g). In the 1000-fold dilution of water-soluble silicate and germanium (50:50), crude saponin content was the highest in 65.69 ㎎/g. Conclusion : From the above results, we concluded that germanium and water-soluble silicates could be useful matters in promoting growth characteristics and saponin content of ginseng (Panax ginseng C.A. Mayer).
        189.
        2016.05 서비스 종료(열람 제한)
        Background : This study was performed to set proper soil moisture tension for promoting seed emergence and yield of ginseng when direct seeding cultivation of ginseng was carried out in shaded plastic house. Methods and Results : The test cultivars were used Cheonpung, Yeonpung, Geumpung and seeds were sown on November 20, 2013. Irrigation starting point was set to 30, 40, 50 kPa and irrigation breakpoint was set to 20 kPa. Ginseng was cultivated in clay loam soil and shading material of plastic house were used blue-white shading vinyl. The emergence rate of 3-year-old ginseng cultivars in accordance with soil moisture tension indicated Cheonpung 97.0%, Yeonpung 95.0%, Geumpung 95.3% in each 50 kPa, 50 kPa, 30 kPa. In general, emergence rate of ginseng was higher tendency in 50 kPa (93.3∼97.0%). The average absolute soil moisture content during the growing season indicated a moisture content of 19.3% (30 kPa), 17.9% (40 kPa), 16.2% (50 kPa). Looking at the growth characteristics in above-ground part of 3-year-old ginseng cultivars according to soil moisture tension, Yeonpung, Cheonpung and Geumpung were good growth tendency in each 30kPa, 40kPa, 50kPa. On the other hand, looking at the growth characteristics in underground part of 3-year-old ginseng cultivars according to soil moisture tension, Cheonpung, Geumpung and Yeonpung were good growth tendency in each 30kPa, 40kPa, 50kPa. Yield per 10a was indicated that Yeonpung was the highest in the 50kPa to 456kg. Yield per 10a of Cheonpung and Geumpung indicated 347kg, 263kg in each 30kPa, 50kPa. Conclusion : From the above results, we concluded that ginseng(Panax ginseng C.A. Mayer) seems to be a difference of growth characteristics according to soil moisture tension. Therefore, it is need to manage soil moisture for each ginseng cultivars
        190.
        2016.05 서비스 종료(열람 제한)
        Background : Aralia cordata and Polygonum multiflorum GAP cultivation requires a stable drying and storage settings after harvesting. therefore, this experiment was performed in order to effectively manage the physical, chemical and biological hazards. Methods and Results : Test materials were used biennial Aralia cordata, Polygonum multiflorum harvested from the medicinal testing ground. The drying temperatures were treated with 40, 50, 6 0℃ and natural drying. Storage containers were stored in plastic boxes, styrofoam boxes and kraft paper containers, examined the color and quality changes for eight months. Aralia cordata and Polygonum multiflorum drying temperature is dry it took natural drying 720 hours, 40℃ hot air drying 180 hours, 50℃ hot air drying 168 hours and 60℃ hot air drying 108 hours. However, the difference chromaticity of the Lab value corresponding to the temperature does not appear, it was good to dry in a short time at 60℃. Aralia cordata and Polygonum multiflorum stored in a styrofoam box storage method but can be stored at room temperature for up to four months, began to decay caused by moisture content it continues to increase. In plastic box in case of Aralia cordata and kraft vessel in case of Polygonum multiflorum can be stored for eight months in room temperature without decay. Styrofoam boxes stored at 5℃ cold storage were higher water absorption such as room temperature, but decay did not occur. Plastic box and styrofoam box were a tendency such as room temperature. Conclusion : Aralia cordata and Polygonum multiflorum are thought that the color change is not large depending on the drying temperature the lower the water content. Styrofoam storage box, the air permeability is higher than plastic boxes and containers Kraft vessel, decay occurs expected increase.
        191.
        2015.09 서비스 종료(열람 제한)
        In animal development, the mechanisms by which localized factors and organelles in egg cytoplasm were exactly distributed into each daughter cell are essential for formation of various cell types. During ascidian Halocynthia roretzi embryogenesis, ooplasmic mitochondria were mainly segregated into muscle and neural precursor cells. At the 32-cell stage, localized mitochondria in the B6.2 blastomeres were preferentially distributed into the B7.4 muscle precursors compared with the B7.3 mesenchyme/ notochord precursors. When the B6.2 blastomeres were isolated from the early 32-cell stage embryos and then allowed to divide 2 times of cell division, the resultant partial embryos showed symmetric distribution of mitochondria, and the partial embryos were composed of equal size cells. In normal development, cell fates of the B7.3 blastomere were correlated with the unequal cleavage of B6.2 lineage cells that normally occurs in the next two-cell division stages to produce a large B8.5 mesenchyme and a small B8.6 notochord cell. Mitochondria are distributed asymmetrically in both cells. When embryos were treated with FGF receptor inhibitor SU5402 and MEK inhibitor U0126 between the 32-cell and the early 64-cell stages, the resultant embryos showed equal cleavage pattern and symmetric distribution of mitochondria in daughter cells of the B6.2 blastomeres. However, blocking of Nodal and Notch signaling did not affect the cell division pattern and mitochondrial distribution in the B6.2 lineage blastomeres between the 32-cell and 110-cell stages. Therefore, it is likely that FGF/MEK signaling is involved in asymmetric distribution of mitochondria and unequal cleavage of the B6.2 lineage blastomeres in ascidian embryo.
        194.
        2014.09 서비스 종료(열람 제한)
        The follicle loss of transplanted ovarian tissue (OT) is caused by ischemia and slow revascularization. To shorten the ischemic period and promote angiogenesis, some angiogenic factors have been treated for transplanted tissues. Angiopoietin-2 (ANG-2) is one of the major angiogenic factors and has been reported to promote blood vessels and increase vascular permeability in the ischemic and/or hypoxic environment. So, this study was designed to assess the impact of ANG-2 on follicle integrity and revascularization of mouse OT grafts. The 5-week-old B6D2F1 female mice were divided into 3 groups (a control and 2 ANG-2 groups) followed by ovary collection and vitrification. After warming, the ovaries were autotransplanted into kidney capsules with/without ANG-2 injection (50 or 500 ng/kg), and then killed at day(D)2, 7, 21 and 42 after transplantation. Total 2,437 follicles in OT grafts were assessed for the follicular density, integrity and classification by H&E staining. Apoptosis, revascularization, and serum FSH levels were evaluated by TUNEL assay, CD31 immunohistochemistry, and ELISA respectively. All the ANG-2 groups showed remarkable increase of morphologically intact follicle ratio across all the grafting duration except D21 (no statistical difference). The numbers of CD31(+) vessels (the sum of 3 fields at ×400 magnification) were significantly increased in both ANG-2 groups compared with the control group at all the grafting duration. Especially at D42, the 500ng ANG-2 group showed significantly more vessels than the 50 ng ANG-2 group as well as the control group. However the mean follicle numbers of grafts, apoptosis ratio and serum FSH levels showed no significant difference among the groups. In this study, remarkably well preserved follicles and larger amount of vessels were appeared in ANG-2 treated groups. So we thought that ANG-2 treatment is effective for OT transplantation and improve transplantation outcomes.
        195.
        2014.09 서비스 종료(열람 제한)
        Ovarian tissue cryopreservation and transplantation causes follicle depletion. To overcome this problem, we investigate the effect of Anti-Müllerian hormone (AMH), a follicle recruitment control hormone, supplementation before and/or after mouse ovarian transplantation. A total of 120 5-week-aged BD F-1 female mice were used. The mice were randomly divided into four groups according to AMH doses (0, 5, 25, 125 μg/mL, respectively). AMH was injected intraperitoneally on every other day for a week before, after, or before and after transplantation of ovaries under kidney capsules was performed. One week after transplantation, follicular normality was evaluated by histological analysis and TUNEL assay. In Group A and C, morphologically intact follicle (G1) ratios of AMH treated groups showed no statistically significant difference. In Group B, G1 ratios of 25 and 125 μg/mL of AMH treated groups were higher than those of 5 μg/mL treated group, but there was no improvement in G1 ratio after AMH treatment. In every group, apoptotic follicle ratios did not show any trend according to AMH treatment. Proportions of primordial follicle were not significantly different according to AMH treatment in all groups. The result of the present study demonstrated that AMH treatment during on transplantation of cryopreserved ovaries has no significant effect on follicle survival and prevention of follicle depletion.
        196.
        2014.09 서비스 종료(열람 제한)
        Objective : To investigate the effects of Simvastatin and Methylprednisolone on ovarian tissue cryopreservation and transplantation using mouse models. Methods : The mice were randomly distributed into 1 control and 3 experimental groups. The B6D2F1 mice were given oral Simvastatin (5 mg/kg), intravenous Methylprednisolone (15 mg/kg), or a combination of both at 2 hours before ovariectomy. Same volume of normal saline was given perorally in the control group at 2 hours before ovariectomy. The ovarian tissues were vitrified accrording to our protocols. The vitrified ovaries were warmed 1 week later and auto-transplanted under bilateral kidney capsules. The ovaries and blood sera were collected at 2, 7 or 21 days after transplantation. Histological analysis, TUNEL assay, immuno-histochemistry for CD31, serum AMH level and embryonic development after in vitro fertilization were assessed for evaluation. Results : With regard to the total grade 1 follicle rate, both Simvastatin or Methylprednisolone treated groups were significantly increased at 2, 7 or 21 days after transplantation (except Simvastatin treated group at 7 days). A combination of Simvastatin and Methylprednisolone group was significantly improved in terms of the total G1 follicle rate, apoptotic follicle rate, CD31 positive area and serum AMH after ovarian tissue transplantation. However, there were no statistically difference with respect to the oocyte maturation rate, blastulation rate, and the other embryonic development parameters after in vitro fertilization procedure among the four groups. Conclusion : Our results suggest that combined donor Simvastatin and Methylprednisolone have beneficial effects on the quality and function of transplanted ovarian tissues.
        197.
        2014.09 서비스 종료(열람 제한)
        Study question: What is the optimal vitrification protocol according to the cryoprotective agent (CPA) for ovarian tissue (OT) cryopreservation? Summary answer: The two-step protocol with 7.5% ethylene glycol (EG) and 7.5% dimethyl sulfoxide (DMSO) for 10 min then 20% EG, 20% DMSO and 0.5 M sucrose for 5 min showed the best results in mouse OT vitrification. What is known already: Establishing the optimal cryopreservation protocol is one of the most important steps to improve OT survival. However, only a few studies have compared vitrification protocols with different CPAs and investigated the effect of in vitro culture (IVC) on vitrified–.warmed OT survival. Some recent papers proposed that a combination of CPAs has less toxicity than one type of CPA. However, the efficacy of different types and concentrations of CPA are not yet well documented. Study design, size, duration: A total of 644 ovaries were collected from 4-week-old BDF1 mice, of which 571 ovaries were randomly assigned to 8 groups and vitrified using different protocols according to CPA composition and the remaining 73 ovaries were used as controls. After warming, each of the eight groups of ovaries was further randomly divided into four subgroups and in vitro cultured for 0, 0.5, 2 and 4 h, respectively. Ovaries of the best two groups among the eight groups were autotransplanted after IVC. Participants/materials, setting, methods: The CPA solutions for the eight groups were composed of EDS, ES, ED, EPS, EF, EFS, E and EP, respectively (E, EG; D, DMSO; P, propanediol; S, sucrose; F, Ficoll). The IVC medium was composed of a-minimal essential medium, 10% fetal bovine serum and 10 mIU/ml follicle-stimulating hormone (FSH). Autotransplantation of vitrified–.warmed OTs after IVC (0 to 4 h) using the EDS or ES protocol was performed, and the grafts were recovered after 3 weeks. Ovarian follicles were assessed for morphology, apoptosis, proliferation and FSH level. Main results and the role of chance: The percentages of the morphologically intact (G1) and apoptotic follicles in each group at 0, 0.5, 2 and 4 h of IVC were compared. For G1 follicles at 0 and 4 h of IVC, the EDS group showed the best results at 63.8 and 46.6%, respectively, whereas the EP group showed the worst results at 42.2 and 12.8%, respectively. The apoptotic follicle ratio was lowest in the EDS group at 0 h (8.1%) and 0.5 h (12.7%) of IVC. All of the eight groups showed significant decreases in G1 follicles and increases in apoptotic follicles as IVC duration progressed. After autotransplantation, the EDS 0 h group showed a significantly higher G1 percentage (84.9%) than did the other groups (42.4–.58.8%), while only the ES 4 h group showed a significant decrease in the number of proliferative cells (80.6%, 87.6–.92.9%). However, no significant differences in apoptotic rates and FSH levels were observed between the groups after autotransplantation. Limitations, reasons for caution: The limitation of this study was the absence of in vitro fertilization using oocytes obtained from OT grafts, which should be performed to confirm the outcomes of ovarian cryopreservation and transplantation. Wider implications of the findings: We compared eight vitrification protocols according to CPA composition and found the EDS protocol to be the optimal method among them. The data presented herein will help improve OT cryopreservation protocols for humans or other animals.
        199.
        2013.08 서비스 종료(열람 제한)
        The mechanisms by which embryo exactly distributes mitochondria into the blastomeres during embryogenesis are one of the important issues in developmental biology. Although the mechanisms has been thought to be important for the proper embryonic development, our understanding has remained limited. In the present study, the distribution of mitochondria was examined in embryos of the ascidian, Halocynthia roretzi, by immunohistochemical staining with three-types of the mitochondria-specific antibodies and vital staining of mitochondria with a fluorescent probe, DiOC2(3). Results of the immunohistochemical staining coincided with that of vital staining, which is able to detect the distribution of mitochondria in cytoplasm of the embryo. Mitochondria was mainly segregated into the B4.1 posterior-vegetal blastomeres at the 8-cell stage. During the next stages, mitochondria was preferentially partitioned into cells of the B-line muscle and the A-line nerve cord precursor compared with each sister cell, endoderm in the 5th cleavage stage, and mesenchyme and notochord in the 6th cleavage stage. However, the mitochondria-rich cytoplasm is divided equally among the blastomeres of the animal hemisphere between the 8-cell and the 64-cell stages. When B6.2 blastomeres were isolated at the early 32-cell stage embryo and cultured in seawater, until control embryos reached the 64-cell stage, pattern of mitochondria distribution was similar to results of the coisolated B7.3 and B7.4 blastomeres from the 64-cell stage embryos. Therefore, it is likely that mitochondria are asymmetrically segregated into the marginal cells in the vegetal hemisphere of the ascidian embryo without cell-cell interaction.
        200.
        2013.08 서비스 종료(열람 제한)
        For the study of population genetic structure with mtDNA, it is essential to measure genetic diversity at each mtDNA regions. Also, to evaluate the variation according to the each region should follow as well as to see if there are differences. In this study, we delved into the variations and dendrogram among samples of seven mtDNA regions (NDⅡ, NDⅤ, NDⅣ, NDⅣL, NDⅥ, NDⅠ, 12SrRNA) from wild Pacific abalone, Haliotis discus hannai collected in Yeosu, Korea. The region with the highest genetic variation was NDⅣ region (Haplotype diversity = 1.0000, Nucleotide diversity = 0.010823) with two to five times higher variation than the others. Furthermore, the study to see if there is a difference between the regions of samples showed that similar aspects of dendrogram in NDⅡ and NDⅠ(divergence of 90% and 87%), which forms a group with hd4, 7, 8 and 10 at bootstrap support, based on 1000 replications. Also, pair-wise FST between clusters within the regions showed high values; 0.4061 (P=0.0000), 0.4805 (P=0.0000) respectively. Therefore we can infer that it is the most efficient and accurate way to analyze the region of NDⅣ with the highest variation in addition to the regions of NDⅡ and NDⅠ, which formed clusters with high bootstrap value, for study of population genetic structure in this species.