• 제목/요약/키워드: Ago

검색결과 2,033건 처리시간 0.036초

Non-canonical targets play an important role in microRNA stability control mechanisms

  • Park, June Hyun;Shin, Chanseok
    • BMB Reports
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    • 제50권4호
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    • pp.158-159
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    • 2017
  • MicroRNAs (miRNAs) regulate gene expression by guiding the Argonaute (Ago)-containing RNA-induced silencing complex (RISC) to specific target mRNA molecules. It is well established that miRNAs are stabilized by Ago proteins, but the molecular features that trigger miRNA destabilization from Ago proteins remain largely unknown. To explore the molecular mechanisms of how targets affect the stability of miRNAs in human Ago (hAgo) proteins, we employed an in vitro system that consisted of a minimal hAgo2-RISC in HEK293T cell lysates. Surprisingly, we found that miRNAs are drastically destabilized by binding to seedless, non-canonical targets. We showed that miRNAs are destabilized at their 3' ends during this process, which is largely attributed to the conformational flexibility of the L1-PAZ domain. Based on these results, we propose that non-canonical targets may play an important regulatory role in controlling the stability of miRNAs, instead of being regulated by miRNAs.

DNA Double-Strand Breaks Serve as a Major Factor for the Expression of Arabidopsis Argonaute 2

  • Lee, Sungbeom;Chung, Moon-Soo;Lee, Gun Woong;Chung, Byung Yeoup
    • 방사선산업학회지
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    • 제10권4호
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    • pp.243-248
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    • 2016
  • Argonaute 2 (AtAGO2) is a well characterized effector protein in Arabidopsis for its functionalities associated with DNA double-strand break (DSB)-induced small RNAs (diRNAs) and for its inducible expression upon ${\gamma}$-irradiation. However, its transcriptional regulation depending on the recovery time after the irradiation and on the specific response to DSBs has been poorly understood. We analyzed the 1,313 bp promoter sequence of the AtAGO2 gene ($1.3kb_{pro}$) to characterize the transcriptional regulation of AtAGO2 at various recovery times after ${\gamma}$-irradiation. A stable transformant harboring $1.3kb_{pro}$ fused with GUS gene showed that the AtAGO2 is highly expressed in response to ${\gamma}$-irradiation, after which the expression of the gene is gradually decreased until 5 days of DNA damage recovery. We also confirm that the AtAGO2 expression patterns are similar to that of ${\gamma}$-irradiation after the treatments of radiomimetic genotoxins (bleomycin and zeocin). However, methyl methanesulfonate and mitomycin C, which are associated with the inhibition of DNA replication, do not induce the expression of the AtAGO2, suggesting that the expression of the AtAGO2 is closely related with DNA DSBs rather than DNA replication.

Holocene Climate Change as Recorded in Mongolian Lake Sediments

  • Khosbayar, P.;Peck, John A.;Ariunbileg, S.;Fowell, Sarah J.;Narantsetseg, Ts.
    • 한국제4기학회지
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    • 제17권2호
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    • pp.25-32
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    • 2003
  • Mongolia, a land-locked country in Central Asia, is located in the region of the highest degree of seasonal contrast on Earth. This paper presents sedimentologic and geomorphic data used to infer Holocene climate change in North-Central Mongolia. Correlation of data show that the climate was cold and dry before 10500 years BP. The post glacial warming occurred from 10500 to 8700 yr BP. The climate was characterized by becoming warmer and dry from 7300 to 6090 radiocarbon years. Between 6100 and 5500 years ago, conditions were hyper arid. Increased effective moisture balance but still arid conditions prevailed between 5500 and 3900 years ago. Since 3900 years ago, generally more humid conditions prevailed and originated varved sediment accumulation. Between about 2300 to 1300 years ago, greater than present day effective moisture balance. Since 1200 years ago climate was cooler and since 600 years ago becoming warmer.

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Climatic Changes During the Past 400,000 Years

  • Yi, HI-Il;Shin, Im-Chul
    • 한국제4기학회지
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    • 제18권2호통권23호
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    • pp.23-31
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    • 2004
  • Temperature variations, and carbon dioxide and methane concentrations are summarized during the past 400,000 years. Atmospheric temperature varied approximately within $10^{\circ}C$ during the past 400,000 years. Most of the time during the past 400,000 years, temperature was lower than today except 410000, 320000, 250000, and 125000 years ago. Temperature was slightly higher or at least similar to today during the time period of 410000. 320000, 250000, and 125000 years ago. The carbon dioxide concentration varied between 180 and 300 ppm, and the methane concentration varied between 40 and 700ppb. The present atmospheric concentration of carbon dioxide is 375 ppm and methane is 1750 ppb. Temperature was 5-$7^{\circ}C$ lower than today during the Last Glacial Maximum(18,000 years ago) and the Younger Dryas(10,000 years ago). Temprature was varied within $1^{\circ}C$ during the past 10,000 years. Especially Middle Holocene Climatic Optimum(6,000 years ago), Medieval Warm Period (500-1,000 years ago), and Little Ice Age(100-500 year ago) were global climatic events. In general, mechanism for the Middle Holocene Climatic Optimum, Medical Warm Period, and Little Ice Age can be explained by the solar insulation, however their exact mechnism is not well known. Carbon dioxide concentration during the past 400,000 years never reached the current value of 375 ppm. Furthermore, the current methane concentration never reached during the past 20Ma. However, current temperature value has happened several times during the past 400,000 years. The implication of this is unsolved question so far. This should be challenged in the near future.

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헤어서비스전문가의 블랙컨슈머 행동지각이 정서적 소진 및 자아탄력성에 미치는 영향 (The Effects of Black Consumer Behavior Perception on Emotional Exhaustion and ago resiliency of Hair Service Professionals)

  • 마은정;고경숙
    • 한국응용과학기술학회지
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    • 제38권4호
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    • pp.974-985
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    • 2021
  • 본 연구는 헤어서비스전문가의 블랙컨슈머 행동지각이 정서적 소진과 자아탄력성에 미치는 영향에 대하여 연구하는 것을 목적으로 한다. 서울, 경기, 전남지역 헤어미용전문가를 대상으로 318부의 설문지가 최종 분석 자료로 사용되었으며 SPSS 26.0 통계 프로그램을 사용하여 분석 되었다. 연구결과는 첫째, 블랙컨슈머 행동지각이 정서적 소진에 정적(+)상관관계를 보였고, 블랙컨슈머 행동지각이 자아탄력성에 부적(-)상관관계를 보였다. 정서적 소진과 자아탄력성은 서로 부적(-)상관관계를 보였다. 둘째, 블랙컨슈머 요인 중 과도성이 정서적 소진에 영향을 미치고 있음이 확인되었다. 셋째, 블랙컨슈머 요인 중 과도성, 상습성이 자아탄력성에 영향을 미치고 있음이 확인되었다. 넷째, 정서적 소진은 자아탄력성에 영향을 미치고 있음이 확인되었다.

도시경관에 대한 주민의식 변화 연구 - 전라남도 영암군을 대상으로 - (A Study on Changes in Residents' Consciousness on Urban Landscape - Focused on Yeongam-gun in Jeollanam-do -)

  • 김윤학;유창균;박성진
    • 한국농촌건축학회논문집
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    • 제23권2호
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    • pp.33-44
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    • 2021
  • In this study, we investigated and analyzed changes about the landscape consciousness of Yeongam-gun residents, in chronological order. As a result, the landscape consciousness of 10 years ago and the present has not changed significantly. Also, the residents' consciousness of the Yeongam-gun landscape image has not changed from 10 years ago, and we recognize that it is necessary to preserve and form the natural landscape. As for the problem of urban landscape, the needs of residents for the development of urban infrastructure facilities and the development of tourist spots are higher than 10 years ago, and the problem of each landscape element is found as the formation and management of a road environment. It was found that the degree of satisfaction with the Yeongam landscape is generally below average, compared to 10 years ago. Residents' willingness to participate in landscape projects has changed as the number of respondents who do not want to participate has increased compared to 10 years ago, and the project method must be promoted by residents / administration / experts as one. The awareness is judged as administrative agencies need to change from the role of regulation-oriented in the past to the role of resident support and cooperation.

AGD(통합치과전문임상의)교육 프로그램 질 보장 방안 (Quality Assurance Strategy for AGO Program in Korea)

  • 신제원
    • 대한치과의사협회지
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    • 제48권11호
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    • pp.790-796
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    • 2010
  • Currently, KDA adopted new post-graduated program; advanced education general dentistry(AGD) for 3 years preparation. The AGO program provides the resident the opportunity to deliver the highest quality of comprehensive dental care to the broadest range of the population with a knowledge, comfort, and ease in treating the high risk patient. The purpose of this article is to study the assurance systems of AGO programs in USA and Japan and to suggest a piece of advice whether we choose the way of AGO program assurance system in Korea.

재활훈련용 이쪽보행 RGO 로봇의 Dynamic PLS 설계와제어 - <응력해석과 FEM을 중심으로> (Design and Control of a Dynamic PLS of the Biped Walking RGO-Robot for a Trainning of Rehabilitation)

  • 김명회;장대진;박창일;박영필
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 춘계학술대회 논문집
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    • pp.238-243
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    • 2002
  • This paper presents a design and a control of a biped walking AGO-robot and dynamic walking simulation for this system. The biped walking RGO-robot is distinguished from other one by which has a very light-weight and a new RGO type with servo motors. The gait of a biped walking AGO-robot depends on the constrains of mechanical kinematics and initial posture. The stability of dynamic walking is investigated by ZMP(Zero Moment Point) of the biped walking AGO-robot. It is designed according to a human wear type and is able to accomodate itself to human environments. The joints of each leg are adopted with a good kinematic characteristics. To test of the analysis of joint kinematic properties, we did the strain stress analysis of dynamic PLS and the study of FEM with a dynamic PLS. It will be expect that the spinal cord injury patients are able to train effectively with a biped walking RGO-robot.

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중(中).한(韓).일(日)에 김치류(類)의 변천(變遷)과 교류(交流)에 관한 연구(硏究) (Studies on movements and interchanges of Kimchi in China, Korea and Japan)

  • 이성우
    • 한국식품영양과학회지
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    • 제4권1호
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    • pp.71-95
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    • 1975
  • The food product, so called 'Kimchi' was first shown as 'Jeo' in a old Chinese book, 'Sigyung', published about 2,600 to 3,600 years ago and it was differentiated into 'Jeo' and 'Jae' in the 'Jure'. The procedure for Kimchi making was explained in detail in the 'Jaeminyosul' and the Kimchi which was made of cereal grains was introduced into Japan through Bacje kingdom with the name of 'susugorisge'. Since then it was developed into characteristic ones of each country. In ancient time of Korea the detail record on Kimchi was not found but it began to show up in a poem written during Korea kingdom. The term of Kimchi which is being used now in Korea was first recorded on a dictionary about 400 years ago, and the Kimchi which used hot pepper was first shown in the 'Sanlimg-yungjae' about 300 years ago. The very favorable Kimchi for Korean containing various kinds of spices, animal foods, fruits, vegetables, seaweeds and 'judgal' was almost completed about 200 years ago and it was recorded in the 'Imwonsibyugi' and the 'Guhabchongsuh'.

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ON THE FORMATION OF GIANT ELLIPTICAL GALAXIES AND GLOBULAR CLUSTERS

  • LEE MYUNG GYOON
    • 천문학회지
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    • 제36권3호
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    • pp.189-212
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    • 2003
  • I review the current status of understanding when, how long, and how giant elliptical galaxies formed, focusing on the globular clusters. Several observational evidences show that massive elliptical galaxies formed at z > 2 (> 10 Gyr ago). Giant elliptical galaxies show mostly a bimodal color distribution of globular clusters, indicating a factor of $\approx$ 20 metallicity difference between the two peaks. The red globular clusters (RGCs) are closely related with the stellar halo in color and spatial distribution, while the blue globular clusters (BGCs) are not. The ratio of the number of the RGCs and that of the BGCs varies depending on galaxies. It is concluded that the BGCs might have formed 12-13 Gyr ago, while the RGCs and giant elliptical galaxies might have formed similarly 10-11 Gyr ago. It remains now to explain the existence of a gap between the RGC formation epoch and the BGC formation epoch, and the rapid metallicity increase during the gap (${\Delta}t{\approx}$ 2 Gyr). If hierarchical merging can form a significant number of giant elliptical galaxies > 10 Gyr ago, several observational constraints from stars and globular clusters in elliptical galaxies can be explained.