• 식물병연구
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• 제26권1호
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• pp.1-7
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• 2020

The succinate dehydrogenase inhibitor (SDHI) is a class of fungicides, which is widely and rapidly used to manage fungal pathogens in the agriculture field. Currently, fungicide resistance to SDHIs has been developed in many different plant pathogenic fungi, causing diseases on crops, fruits, vegetables, and turf. Understanding the molecular mechanisms of fungicide resistance is important for effective prevention and resistance management strategies. Two different mechanisms have currently been known in SDHI resistance. The SDHI target genes, SdhB, SdhC, and SdhD, mutation(s) confer resistance to SDHIs. In addition, overexpression of ABC transporters is involved in reduced sensitivity to SDHI fungicides. In this review, the current status of SDHI resistance mechanisms in phytopathogenic fungi is discussed.

• Osteoporosis and Sarcopenia
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• 제3권3호
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• pp.117-122
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• 2017

Sarcopenia is the degenerative loss of muscle mass and function with aging. Recently sarcopenia was recognized as a clinical disease by the International Classification of Disease, 10th revision, Clinical Modification. An imbalance between protein synthesis and degradation causes a gradual loss of muscle mass, resulting in a decline of muscle function as a progress of sarcopenia. Many mechanisms involved in the onset of sarcopenia include age-related factors as well as activity-, disease-, and nutrition-related factors. The stage of sarcopenia reflecting the severity of conditions assists clinical management of sarcopenia. It is important that systemic descriptions of the disease conditions include age, sex, and other environmental risk factors as well as levels of physical function. To develop a new therapeutic intervention needed is the detailed understanding of molecular and cellular mechanisms by which apoptosis, autophagy, atrophy, and hypertrophy occur in the muscle stem cells, myotubes, and/or neuromuscular junction. The new strategy to managing sarcopenia will be signal-modulating small molecules, natural compounds, repurposing of old drugs, and muscle-specific microRNAs.

• Molecules and Cells
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• 제42권4호
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• pp.285-291
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• 2019

Eukaryotic cells use conserved quality control mechanisms to repair or degrade defective proteins, which are synthesized at a high rate during proteotoxic stress. Quality control mechanisms include molecular chaperones, the ubiquitin-proteasome system, and autophagic machinery. Recent research reveals that during autophagy, membrane-bound organelles are selectively sequestered and degraded. Selective autophagy is also critical for the clearance of excess or damaged protein complexes (e.g., proteasomes and ribosomes) and membrane-less compartments (e.g., protein aggregates and ribonucleoprotein granules). As sessile organisms, plants rely on quality control mechanisms for their adaptation to fluctuating environments. In this mini-review, we highlight recent work elucidating the roles of selective autophagy in the quality control of proteins and RNA in plant cells. Emphasis will be placed on selective degradation of membrane-less compartments and protein complexes in the cytoplasm. We also propose possible mechanisms by which defective proteins are selectively recognized by autophagic machinery.

• Molecules and Cells
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• 제42권3호
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• pp.237-244
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• 2019

Understanding the mechanisms of cancer drug resistance is a critical challenge in cancer therapy. For many cancer drugs, various resistance mechanisms have been identified such as target alteration, alternative signaling pathways, epithelial-mesenchymal transition, and epigenetic modulation. Resistance may arise via multiple mechanisms even for a single drug, making it necessary to investigate multiple independent models for comprehensive understanding and therapeutic application. In particular, we hypothesize that different resistance processes result in distinct gene expression changes. Here, we present a web-based database, CDRgator (Cancer Drug Resistance navigator) for comparative analysis of gene expression signatures of cancer drug resistance. Resistance signatures were extracted from two different types of datasets. First, resistance signatures were extracted from transcriptomic profiles of cancer cells or patient samples and their resistance-induced counterparts for >30 cancer drugs. Second, drug resistance group signatures were also extracted from two large-scale drug sensitivity datasets representing ~1,000 cancer cell lines. All the datasets are available for download, and are conveniently accessible based on drug class and cancer type, along with analytic features such as clustering analysis, multidimensional scaling, and pathway analysis. CDRgator allows meta-analysis of independent resistance models for more comprehensive understanding of drug-resistance mechanisms that is difficult to accomplish with individual datasets alone (database URL: http://cdrgator.ewha.ac.kr).

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2207-2212
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• 2013

Cancer prevention is rapidly emerging as a major strategy to reduce cancer mortality. In the field of breast cancer, significant strides have recently been made in the understanding of underlying preventive mechanisms. Currently, three major strategies have been linked to an increase in breast cancer risk: obesity, lack of physical exercise, and high levels of saturated dietary fat. As a result, prevention strategies for breast cancer are usually centered on these lifestyle factors. Unfortunately, there remains controversy regarding epidemiological studies that seek to determine the benefit of these lifestyle changes. We have identified crucial mechanisms that may help clarify these conflicting studies. For example, recent reports with olive oil have demonstrated that it may influence crucial transcription factors and reduce breast tumor aggressiveness by targeting HER2. Similarly, physical exercise reduces sex hormone levels, which may help protect against breast cancer. Obesity promotes tumor cell growth and cell survival through upregulation of leptin and insulin-like growth factors. This review seeks to discuss these underlying mechanisms, and more behind the three major prevention strategies, as a means of understanding how breast cancer can be prevented.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.63.2-63.2
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• 2015

Controlling and sensing spin states of magnetic molecules such as metallo-porphyrins at the single molecule level is essential for spintronic molecular device applications. Axial coordinations of diatomic molecules to metallo-porphyrins also play key roles in dynamic processes of biological functions such as blood pressure control and immune response. However, probing such reactions at the single molecule level to understand their physical mechanisms has been rarely performed. Here we present on our single molecule association and dissociation experiments between diatomic and metallo-porphyrin molecules on Au(111) describing its adsorption structures, spin states, and dissociation mechanisms. We observed bright ring shapes in NO adsorbed metallo-porphyrin compelxes and explained them by considering tilted binding and precession motion of NO. Before NO exposure, Co-porphryin showed a clear zero-bias peak in scanning tunneling spectroscopy, a signature of Kondo effect in STS, whereas after NO exposures it formed a molecular complex, NO-Co-porphyrin, that did not show any zero-bias feature implying that the Kondo effect was switched off by binding of NO. Under tunneling junctions of scanning tunneling microscope, both positive and negative energy pulses. From the observed power law relations between dissociation rate and tunneling current, we argue that the dissociations were inelastically induced with molecular orbital resonances. Our study shows that single molecule association and dissociation can be used to probe spin states and reaction mechanisms in a variety of axial coordination between small molecules and metallo-porphyrins.

• 한국발생생물학회지:발생과생식
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• 제21권4호
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• pp.467-473
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• 2017

Ascidian embryos have become an important model for embryological studies, offering a simple example for mechanisms of cytoplasmic components segregation. It is a well-known example that the asymmetric segregation of mitochondria into muscle lineage cells occurs during ascidian embryogenesis. However, it is still unclear which signaling pathway is involved in this process. To obtain molecular markers for studying mechanisms involved in the asymmetric distribution of mitochondria, we have produced monoclonal antibodies, Mito-1, Mito-2 and Mito-3, that specifically recognize mitochondria-rich cytoplasm in cells of the ascidian Halocynthia roretzi embryos. These antibodies stained cytoplasm like reticular structure in epidermis cells, except for nuclei, at the early tailbud stage. Similar pattern was observed in vital staining of mitochondria with DiOC2, a fluorescent probe of mitochondria. Immunostaining with these antibodies showed that mitochondria are evenly distributed in the animal hemisphere blastomeres at cleavage stages, whereas not in the vegetal hemisphere blastomeres. Mitochondria were transferred to the presumptive muscle and nerve cord lineage cells of the marginal zone in the vegetal hemisphere more than to the presumptive mesenchyme, notochord and endoderm lineage of the central zone. Therefore, it is suggested that these antibodies will be useful markers for studying mechanisms involved in the polarized distribution of mitochondria during ascidian embryogenesis.

• Journal of Ginseng Research
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• 제48권2호
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• pp.129-139
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• 2024

Liver diseases are a significant global health burden and are among the most common diseases. Ginssennoside Rg3 (Rg3), which is one of the most abundant ginsenosides, has been found to have significant preventive and therapeutic effects against various types of diseases with minimal side effects. Numerous studies have demonstrated the significant preventive and therapeutic effects of Rg3 on various liver diseases such as viral hepatitis, acute liver injury, nonalcoholic liver diseases (NAFLD), liver fibrosis and hepatocellular carcinoma (HCC). The underlying molecular mechanism behind these effects is attributed to apoptosis, autophagy, antioxidant, anti-inflammatory activities, and the regulation of multiple signaling pathways. This review provides a comprehensive description of the potential molecular mechanisms of Rg3 in the development of liver diseases. The article focuses on the regulation of apoptosis, oxidative stress, autophagy, inflammation, and other related factors. Additionally, the review discusses combination therapy and liver targeting strategy, which can accelerate the translation of Rg3 from bench to bedside. Overall, this article serves as a valuable reference for researchers and clinicians alike.

• Biomolecules & Therapeutics
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• 제15권1호
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• pp.7-15
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• 2007

There have been various animal models of skin inflammation. These models have been used for establishing anti-inflammatory activity of the topical agents including cosmetics. Here, the molecular mechanisms of most widely-used animal models of skin inflammation including contact irritation, acute and chronic inflammation, and delayed-type hypersensitivity are summarized. Against these animal models, varieties of plant flavonoids showed anti-inflammatory activity. The action mechanisms of anti-inflammation by topical flavonoids are presented. A therapeutic potential of flavonoids is discussed.

• Journal of Magnetics
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• 제10권3호
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• pp.108-112
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• 2005

GaAs nanowires were grown on GaAs (111)B substrates in a gas source molecular beam epitaxy system, using self-assembled Au particles with diameters between 25 and 200 nm as the catalytic agents. The growth rate and structure of the nanowires were investigated for substrate temperatures between 500 and $600^{\circ}C$ to study the mass transport mechanisms that drive the growth of these crystals. The possibilities for fabrication of novel magnetic nanostructures by suitable choice of growth conditions are discussed.