• Title/Summary/Keyword: natural role play

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HspA and HtpG Enhance Thermotolerance in the Cyanobacterium, Microcystis aeruginosa NIES-298

  • Rhee, Jae-Sung;Ki, Jang-Seu;Kim, Bo-Mi;Hwang, Soon-Jin;Choi, Ik-Young;Lee, Jae-Seong
    • Journal of Microbiology and Biotechnology
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    • v.22 no.1
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    • pp.118-125
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    • 2012
  • Heat shock proteins (Hsps) play a key role in the cellular defense response to diverse environmental stresses. Here, the role of Hsp genes in the acquisition of thermotolerance in the cyanobacterium Microcystis aeruginosa NIES-298 was investigated. Twelve Hsp-related genes were examined to observe their modulated expression patterns at different temperatures (10, 15, 25, and $35^{\circ}C$) over different exposure periods. HspA and HtpG transcripts showed an up-regulation of expression at low temperatures (10 and $15^{\circ}C$) and high temperature ($35^{\circ}C$), compared with the control ($25^{\circ}C$). To examine their effects upon thermotolerance, we purified recombinant HspA and HtpG proteins. During a thermotolerance study at $54^{\circ}C$, the HspA-transformed bacteria showed increased thermotolerance compared with the control. HtpG also played a role in the defense response to acute heat stress within 30 min. These findings provide a better understanding of cellular protection mechanisms against heat stress in cyanobacteria.

Role of endometrial immune cells in implantation

  • Lee, Ji-Yeong;Lee, Millina;Lee, Sung-Ki
    • Clinical and Experimental Reproductive Medicine
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    • v.38 no.3
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    • pp.119-125
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    • 2011
  • Implantation of an embryo occurs during the mid-secretory phase of the menstrual cycle, known as the "implantation window." During this implantation period, there are significant morphologic and functional changes in the endometrium, which is followed by decidualization. Many immune cells, such as dendritic and natural killer (NK) cells, increase in number in this period and early pregnancy. Recent works have revealed that antigen-presenting cells (APCs) and NK cells are involved in vascular remodeling of spiral arteries in the decidua and lack of APCs leads to failure of pregnancy. Paternal and fetal antigens may play a role in the induction of immune tolerance during pregnancy. A balance between effectors (i.e., innate immunity and helper T [Th] 1 and Th17 immunity) and regulators (Th2 cells, regulatory T cells, etc.) is essential for establishment and maintenance of pregnancy. The highly complicated endocrine-immune network works in decidualization of the endometrium and at the fetomaternal interface. We will discuss the role of immune cells in the implantation period and during early pregnancy.

An Overview on Plant Derived Phenolic Compounds and Their Role in Treatment and Management of Diabetes

  • Deka, Himangshu;Choudhury, Ananta;Dey, Biplab Kumar
    • Journal of Pharmacopuncture
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    • v.25 no.3
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    • pp.199-208
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    • 2022
  • Objectives: In recent decades, the trend for treating diabetes mellitus (DM) has shifted toward alternative medicines that are obtained from plant sources. Existing literature suggests that phenolic compounds derived from plants possess promising health-promoting properties. This study aimed to discuss the role of plant-derived phenolic compounds in the effective treatment and management of diabetes. Methods: Information about plant secondary metabolites, phenolic compounds, and their role in the treatment and management of diabetes was collected from different databases, such as Pubmed, ScienceDirect, Scopus, and Google Scholar. Keywords like secondary metabolites, phenolic compounds, simple phenol, flavonoids, lignans, stilbenes, and diabetes were searched. Research and review articles with relevant information were included in the study. Results: Anti-diabetic studies of the four major classes of phenolic compounds were included in this review. The plant-derived phenolic compounds were reported to have potent anti-diabetic activities. However, each class of phenolic compounds was found to behave differently according to various mechanisms. Conclusion: The obtained results suggest that phenolic compounds derived from natural sources display promising anti-diabetic activities. Based on the available information, it can be concluded that phenolic compounds obtained from various natural sources play key roles in the treatment and management of diabetes.

Molecular cloning and characterization of a soybean GmMBY184 induced by abiotic stresses

  • Chung, Eun-Sook;Kim, Koung-Mee;Lee, Jai-Heon
    • Journal of Plant Biotechnology
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    • v.39 no.3
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    • pp.175-181
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    • 2012
  • Drought and high salinity stresses often imposes adverse effects on crop yield. MYB transcription factors have been shown to be an important regulator in defense responses to these environmental stresses. In this study, we have cloned and characterized a soybean gene GmMYB184 (Glycine max MYB transcription factor 184). Deduced amino acid sequences of GmMYB184 show highest homology with that from Vitis vinifera legume plant (75%). Different expression patterns of GmMYB184 mRNA were observed subjected to drought, cold, high salinity stress and abscisic acid treatment, suggesting its role in the signaling events in the osmotic stress-related defense response. Subcellular localization studies demonstrated that the GFP-GmMYB184 fusion protein was localized in the nucleus. Using the yeast assay system, the C-terminal region of GmMYB184 was found to be essential for the transactivation activity. These results indicate that the GmMYB184 may play a role in abiotic stress tolerance in plant.

Litter Decomposition Process in Coffee Agroforestry Systems

  • Petit-Aldana, Judith;Rahman, Mohammed Mahabubur;Parraguirre-Lezama, Conrado;Infante-Cruz, Angel;Romero-Arenas, Omar
    • Journal of Forest and Environmental Science
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    • v.35 no.2
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    • pp.121-139
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    • 2019
  • Decomposition of litter is a function of various interrelated variables, both biotic and abiotic factors. Litter decomposition acts like a natural fertilizer play a prime role in maintaining the productivity and nutrient cycling in agroforestry systems. There are few studies of decomposition carried out in agroforestry systems with coffee; so it is necessary to perform more research work to fill the research gap, which will allow a better understanding of the management of the coffee agroforestry systems. This paper is based on the theoretical and conceptual aspects of leaf litter decomposition in agroforestry systems, emphasizing the combination with coffee cultivation and critically examined the role of the different factors involved in the decomposition. This study made a comparison of different investigations with regards to weight loss, decomposition rates (k), initial chemical composition, and release of the main nutrients. This study suggested that it is necessary to implement studies of decomposition and mineralization, and the microflora and fauna associated with these processes, so that serves as an important tool to develop a model for enabling a description of the short, medium, and long-term dynamics of soil nutrients in coffee agroforestry systems.

Natural Killer Cell and Cancer Immunotherapy (자연살해세포와 항암면역치료)

  • Kim, Hun Sik
    • Hanyang Medical Reviews
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    • v.33 no.1
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    • pp.59-64
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    • 2013
  • Cancer remains the leading cause of death worldwide despite intense efforts in developing innovative treatments. Current approaches in cancer therapy are mainly directed to a selective targeting of cancer cells to avoid potential side effects associated with conventional therapy. In this respect, Natural killer (NK) cells have gained growing attention and are now being considered as promising therapeutic tools for cancer therapy owing to their intrinsic ability to rapidly recognize and kill cancer cells, while sparing normal healthy cells. NK cells play a key role in the first line of defense against transformed and virus-infected cells. NK cells sense their target through a whole array of receptors, both activating and inhibitory. Functional outcome of NK cell against target cells is determined by the balance of signals transmitted from diverse activating and inhibiting receptors. Despite significant progress made in the role of NK cells attack as a pivotal sentinel in tumor surveillance, the molecular has been that regulate NK cell responses remain unclear, which restricts the use of NK cells as a therapeutic measure. Accordingly, current efforts for NK cell-based cancer therapy have largely relied on the strategies that are based on the manipulation of inhibitory receptor function. However, if we better understand the mechanisms governing NK cell activation, including those mediated by diverse activating receptors, this knowledge can be applied to the development of optimal design for cancer immunotherapy by targeting NK cells.

Insect natural enemies as bioindicators in rice paddies

  • Ueno, Takatoshi
    • Korean Journal of Agricultural Science
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    • v.39 no.4
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    • pp.545-553
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    • 2012
  • In Asia, including Japan and Korea, rice paddies occupy the largest cultivated area in agricultural land. Rice paddies provide the habitats for many organisms including endemic species, sustaining high biodiversity. Insect natural enemies inhabiting rice paddies have an important function for rice production as agents of 'ecosystem services' because they play a major role in suppressing rice pests. The diversity and abundance of natural enemies can be a good index reflecting the 'healthiness' of agro-ecosystem services in rice paddies. The present study investigates whether insect natural enemies could be good biological indicators for general arthropod biodiversity and agricultural practice. First, the concept of ideal bio-indicators was summarized. The strategy to explore and select such bio-indicators was then proposed. Lastly, field survey was made to evaluate the abundance and biodiversity of natural enemies in Japanese rice paddies where chemical inputs, i.e., insecticide use, were different. The results showed that reduction of chemical inputs led to an increase in species richness or diversity of natural enemies including parasitoids and predators. Then, the data were analyzed to examine suitable indicator species to assess environmental soundness of agricultural practice and biodiversity in rice paddies. The density of several species of natural enemies did respond both to pesticide use and to general arthropod biodiversity. The analyses thus have indicated that natural enemies can be suitable as bio-indicators. Usefulness of indicator species in rice paddies is discussed in the context of ecologically sound agriculture.

SET7-mediated TIP60 methylation is essential for DNA double-strand break repair

  • Song Hyun, Kim;Junyoung, Park;Jin Woo, Park;Ja Young, Hahm;Seobin, Yoon;In Jun, Hwang;Keun Pil, Kim;Sang-Beom, Seo
    • BMB Reports
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    • v.55 no.11
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    • pp.541-546
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    • 2022
  • The repair of DNA double-strand breaks (DSBs) by homologous recombination (HR) is crucial for maintaining genomic integrity and is involved in numerous fundamental biological processes. Post-translational modifications by proteins play an important role in regulating DNA repair. Here, we report that the methyltransferase SET7 regulates HR-mediated DSB repair by methylating TIP60, a histone acetyltransferase and tumor suppressor involved in gene expression and protein stability. We show that SET7 targets TIP60 for methylation at K137, which facilitates DSB repair by promoting HR and determines cell viability against DNA damage. Interestingly, TIP60 demethylation is catalyzed by LSD1, which affects HR efficiency. Taken together, our findings reveal the importance of TIP60 methylation status by SET7 and LSD1 in the DSB repair pathway.

Cell Cycle-dependent Expression of Chitin Synthase Genes in Aspergillus nidulans

  • Park, Bum-Chan;Maeng, Pil-Jae;Park, Hee-Moon
    • Journal of Microbiology
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    • v.39 no.1
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    • pp.74-78
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    • 2001
  • The transcription of the chitin synthase genes (chss) was cell cycle-regulated in Aspergillus nidulans and the expression pattern was classified into two groups. Group one, containing chsA and chsC, showed decreasing transcription level upon entry into the S-phase and no further variation during the remainder of the cell cycle. However, group two, containing chsB, chsD, and csmA showed a sharp decrease of mRNA level upon entry into the G2-phase and an increase during the M-phase. Our results suggested that the chss, belonging to same group with the similar expression pattern during the cell cycle are functionally linked and that chsD may play a role in hyphal growth and development in A. nidulans.

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Accumulation of Heavy Metals in the Antarctic Clam Laternula elliptica

  • Lee, Yong-Seok;Jeong, Kye-Heon
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2004.06a
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    • pp.87-91
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    • 2004
  • Immunohistochemical and ultrastructural experiments were conducted to find out heavy metal accumulation in some selected organs such as the kidney, the hepatopancreas, and the gills of the Antarctic Clam Laternula elliptica According to the immunohistochemical study the subject organs of the clam showed reactions indicating the presence of MT(metallothionein), a metal-binding protein involved in metal detoxifying process. Examination under the transmission electron microscope also revealed that other ligands(e.g. metal-rich granules in the kidney) may play a role in metal accumulating and detoxifying process in L. elliptica. In the artificial exposure of the clam to Cd, it showed immediate subcellular responses, suggesting that this species can be used as rapid and efficient bioindicators for Cd exposure in natural environment.

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