• Title/Summary/Keyword: Changes in roles

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Digital Libraries as Scocio-Technical Interaction Networks: American Memory Project as one example of it (사회기술상호작용망(STIN)으로서의 디지털 도서관: American Memory Project를 중심으로)

  • Joung, Kyoung-Hee
    • Journal of the Korean Society for information Management
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    • v.20 no.4 s.50
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    • pp.91-111
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    • 2003
  • This paper shows that digital libraries can be understood through STIN models which emphasize interactions among components in networks. The enrollment strategies in the American Memory make human and non-human factors interact. Specifically, this paper articulates that the relationships between users and collections, between users and staff, and between users and users are closely linked through the strategies . Observing the linkages among these components ,this paper found that the enrollment processes not only draw users to the American Memory, but also alter roles of components and creates new roles and players for them. The alterations of roles and the resulting changes of relationships among components mean that digital libraries lead to transform the grounding of knowledge works in a society.

New Insights into the Protein Turnover Regulation in Ethylene Biosynthesis

  • Yoon, Gyeong Mee
    • Molecules and Cells
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    • v.38 no.7
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    • pp.597-603
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    • 2015
  • Biosynthesis of the phytohormone ethylene is under tight regulation to satisfy the need for appropriate levels of ethylene in plants in response to exogenous and endogenous stimuli. The enzyme 1-aminocyclopropane-1-carboxylic acid synthase (ACS), which catalyzes the rate-limiting step of ethylene biosynthesis, plays a central role to regulate ethylene production through changes in ACS gene expression levels and the activity of the enzyme. Together with molecular genetic studies suggesting the roles of post-translational modification of the ACS, newly emerging evidence strongly suggests that the regulation of ACS protein stability is an alternative mechanism that controls ethylene production, in addition to the transcriptional regulation of ACS genes. In this review, recent new insight into the regulation of ACS protein turnover is highlighted, with a special focus on the roles of phosphorylation, ubiquitination, and novel components that regulate the turnover of ACS proteins. The prospect of cross-talk between ethylene biosynthesis and other signaling pathways to control turnover of the ACS protein is also considered.

Gliotoxin-Induced Oxidative Stress Mediates the Apoptotic Death in Human Leukemic HL-60 cells (진균독소 Gliotoxin-유도성 산화적 손상에 의한 Apoptosis)

  • 장해란;김영희;김남송;원진숙;조정환;윤재도;임창인;김호찬;최익준
    • Toxicological Research
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    • v.18 no.3
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    • pp.275-283
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    • 2002
  • Fungal metabolite, gliotoxin is an epipolythiodioxopiperazin (ETP) class and has various roles including immunomodulatory and apoptotic effects. This study was designed to evaluate the mechanism by which gliotoxin exerts the apoptosis on human promyelocytic leukemic HL-60 cells. Herein, we demonstrated that the gliotoxin decreased the cell viability in a time-dependent manner Gliotoxin-induced cell death was confirmed us apoptosis characterized by chromatin condensation and ladder-pattern fragmentation of genomic DNA. Gliotoxin increased the catalytic activities of caspase-3 and caspase-9. Activation of caspase-3 was further confirmed by degradation of procaspase-3 and poly(ADP-ribose) polymerase (PARP) by gliotoxin in HL-60 cells. Furthermore, gliotoxin induced the changes of mitochondrial transmembrane potential (MTP). Antioxidants, including GSH and NAC, markedly inhibited apoptosis with conistent suppression of enzymatic activity of caspase-3, caspase-9, and MTP loss in gliotoxin-treated cells. Taken together, we suggest that gliotoxin function as an oxidant and ploys proapoptotic roles in HL-60 cells via activation of intrinsic caspase cascades as well as mitochondrial dysfunction.

GRIs in the United States: Policy Directions Old and New

  • Bozeman, Barry
    • STI Policy Review
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    • v.3 no.1
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    • pp.139-161
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    • 2012
  • The United States National Innovation system has many distinctive aspects and its government research institutes (GRI's) play a variety of important roles within the overall system. This paper reviews issues pertaining to U.S. GRI's but within the broader concept of US science and technology policy. After presenting an overview of the GRI's in this broader context, the paper presents a brief historical analysis of changes in the roles and deployment of U.S. GRI's. After identifying unique features of GRI's (ones that separate the U.S. GRI's from other nations) the paper concludes by identifying the ways in which the U.S. experience may be relevant to other nations such as Korea. The lessons include the competition-cooperation with large-scale and multidisciplinary university research centers, the use of GRI's to promote sharing and efficiencies in fundamental scientific equipment and resources, and the ability of GRI's to accelerate the development of science and technology.

Colors in Narratives of 3D Animation (3D애니메이션에서의 내러티브에 의한 색채)

  • Yim, Yu-Sang;Koh, Wook
    • The Journal of the Korea Contents Association
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    • v.9 no.4
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    • pp.162-171
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    • 2009
  • In directing a film, aesthetics are use for visual manifestation of narratives to audiences. Especially, colors have important roles in that process to express emotions and to convey the story. For 3D animation, they may play even more important roles due to the nature of colors being generated by computers. This paper studies the relationship between narratives and colors by analyzing how colors change by the rise and fall of tensions in narratives, and by investigating how emotional expressions are affected due to color changes.

Histone H4-Specific Deacetylation at Active Coding Regions by Hda1C

  • Lee, Min Kyung;Kim, TaeSoo
    • Molecules and Cells
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    • v.43 no.10
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    • pp.841-847
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    • 2020
  • Histone acetylation and deacetylation play central roles in the regulation of chromatin structure and transcription by RNA polymerase II (RNA Pol II). Although Hda1 histone deacetylase complex (Hda1C) is known to selectively deacetylate histone H3 and H2B to repress transcription, previous studies have suggested its potential roles in histone H4 deacetylation. Recently, we have shown that Hda1C has two distinct functions in histone deacetylation and transcription. Histone H4-specific deacetylation at highly transcribed genes negatively regulates RNA Pol II elongation and H3 deacetylation at inactive genes fine-tunes the kinetics of gene induction upon environmental changes. Here, we review the recent understandings of transcriptional regulation via histone deacetylation by Hda1C. In addition, we discuss the potential mechanisms for histone substrate switching by Hda1C, depending on transcriptional frequency and activity.

Detecting DNA hydroxymethylation: exploring its role in genome regulation

  • Sun-Min Lee
    • BMB Reports
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    • v.57 no.3
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    • pp.135-142
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    • 2024
  • DNA methylation is one of the most extensively studied epigenetic regulatory mechanisms, known to play crucial roles in various organisms. It has been implicated in the regulation of gene expression and chromatin changes, ranging from global alterations during cell state transitions to locus-specific modifications. 5-hydroxymethylcytosine (5hmC) is produced by a major oxidation, from 5-methylcytosine (5mC), catalyzed by the ten-eleven translocation (TET) enzymes, and is gradually being recognized for its significant role in genome regulation. With the development of state-of-the-art experimental techniques, it has become possible to detect and distinguish 5mC and 5hmC at base resolution. Various techniques have evolved, encompassing chemical and enzymatic approaches, as well as third-generation sequencing techniques. These advancements have paved the way for a thorough exploration of the role of 5hmC across a diverse array of cell types, from embryonic stem cells (ESCs) to various differentiated cells. This review aims to comprehensively report on recent techniques and discuss the emerging roles of 5hmC.

Frequent Changes of 3' UTR Sequences in the Genes Expressed During Hematopoietic Differentiation Implicates the Importance of 3' UTR in Regulation of Gene Function (조혈세포의 분화과정에서 발현되는 유전자의 3‘ UTR 염기서열의 변화가 유전자 기능의 조절에 미치는 영향에 대한 연구)

  • Lee Sanggyu
    • YAKHAK HOEJI
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    • v.49 no.3
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    • pp.205-211
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    • 2005
  • The 3' UTR (3' untranslated region) plays important roles in controlling gene expression through regulating 3' polyadenylation, mRNA export, subcellular localization, translational efficiency, and mRNA stability. Changes in the 3' UTR sequence in an expressed transcript can result in functional changes of the genes that are expressed in pathological conditions compared with those genes expressed in normal physiologic conditions. A genome-wide survey of 3' UTR variation was performed for the genes expressed during hematopoietic differentiation from CD34+ stem/progenitor cells to CD 15 + myeloid progenitor cells. Wide-spread differential usage of the 3' UTR was observed from the genes expressed during this cellular transition. This study implies that the 3' UTR can be a highly coordinated region for post-transcriptional regulation of the function of expressed genes.

Male and Female College Students' Family-related Gender Role Attitudes : Changes from 1991 to 2002 (1991년도와 2002년도 남녀 대학생의 가정내 역할에 대한 성역할 태도)

  • Whaung, Eun
    • Journal of Families and Better Life
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    • v.22 no.1
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    • pp.77-89
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    • 2004
  • The study examined the shift in the attitudes of college students regarding familial gender roles between 1991 to 2002. The results are as follows. (a)There were changes toward the egalitarian direction in familial-related gender role attitudes between 1991 and 2002, in both male and female college students. (b)Yet, despite of these changes toward egalitarianism, Female colleges students exhibited the more egalitarian familial gender role attitudes than their male counterparts, both in 1991 and 2002. (c)The shift toward more egalitarian attitudies was most pronounced in couples' equal participation in decision making, the sharing of housework, and women's participation in labor force. however, the shift toward egalitarian attitudies was less pronounced in the issues concerning outside home activities of the mothers with infants. Based on the results, implication for the future family and family education programs were discussed.

Changes in Endophyte Communities across the Different Plant Compartments in Response to the Rice Blast Infection

  • Mehwish Roy;Sravanthi Goud Burragoni;Junhyun Jeon
    • The Plant Pathology Journal
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    • v.40 no.3
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    • pp.299-309
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    • 2024
  • The rice blast disease, caused by the fungal pathogen, Magnaporthe oryzae (syn. Pyricularia oryzae), poses a significant threat to the global rice production. Understanding how this disease impacts the plant's microbial communities is crucial for gaining insights into host-pathogen interactions. In this study, we investigated the changes in communities of bacterial and fungal endophytes inhabiting different compartments in healthy and diseased plants. We found that both alpha and beta diversities of endophytic communities do not change significantly by the pathogen infection. Rather, the type of plant compartment appeared to be the main driver of endophytic community structures. Although the overall structure seemed to be consistent between healthy and diseased plants, our analysis of differentially abundant taxa revealed the specific bacterial and fungal operational taxonomic units that exhibited enrichment in the root and leaf compartments of infected plants. These findings suggest that endophyte communities are robust to the changes at the early stage of pathogen infection, and that some of endophytes enriched in infected plants might have roles in the defense against the pathogen.