• BMB Reports
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• 제45권12호
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• pp.719-723
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• 2012

A close association between the obesity hormone leptin and breast cancer progression has been suggested. The present study investigated the molecular mechanism for enhanced leptin expression in breast cancer cells and its functional significance in breast cancer aggressiveness. We examined whether leptin expression level is affected by the oncoprotein human epidermal growth factor receptor2 (HER2), which is overexpressed in ~30% of breast tumors. Here, we report, for the first time, that HER2 induces transcriptional activation of leptin in MCF10A human breast epithelial cells. We also showed that p38 mitogen-activated protein kinase signaling was involved in leptin expression induced by HER2. We showed a crucial role of leptin in the invasiveness of HER2-MCF10A cells using an siRNA molecule targeting leptin. Taken together, the results indicate a molecular link between HER2 and leptin, providing supporting evidence that leptin represents a target for breast cancer therapy.

• BMB Reports
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• 제46권9호
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• pp.429-438
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• 2013

Aging is the strongest risk factor for cancer development, suggesting that molecular crosstalks between aging and tumorigenesis exist in many cellular pathways. Recently, Sirtuins (Sirt1-7), the mammalian homologues of aging-related $sir2{\alpha}$ in yeast, have been shown to modulate several major cellular pathways, such as DNA repair, inflammation, metabolism, cell death, and proliferation in response to diverse stresses, and may serve as a possible molecular link between aging and tumorignenesis. In addition, growing evidence suggests that sirtuins are directly implicated in the development of cancer, and they can act as either a tumor suppressor or promoter, depending on the cellular context and tumor types. While the functions of Sirt1 in tumorigenesis have been reported and reviewed in many studies, the connection between sirtuins 2-7 and the development of cancer is less established. Thus, this review will present the recent updates on the emerging roles of Sirt2-7 members in carcinogenesis.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2783-2785
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• 2010

Searching for new molecular radicals which are believed to play an important role as reaction intermediates in aromatic chain reactions, we have applied the technique of corona excited supersonic expansion employing a pinhole-type glass nozzle to obtain the vibronic spectrum from the corona discharge of precursor 3,5-difluorotoluene with a large amount of inert carrier gas helium. An analysis of the observed spectrum revealed that many vibronic bands are from other isomeric difluorobenzyl radicals generated in the jet by migration of the fluorine atom or methylene group to the adjacent position in the 3,5-difluorobenzyl radical. A possible mechanism was proposed for the formation of other isomers by using a bridged cyclic intermediate structure.

• Molecules and Cells
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• 제43권2호
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• pp.176-181
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• 2020

The RUNX transcription factors serve as master regulators of development and are frequently dysregulated in human cancers. Among the three family members, RUNX3 is the least studied, and has long been considered to be a tumor-suppressor gene in human cancers. This idea is mainly based on the observation that RUNX3 is inactivated by genetic/epigenetic alterations or protein mislocalization during the initiation of tumorigenesis. Recently, this paradigm has been challenged, as several lines of evidence have shown that RUNX3 is upregulated over the course of tumor development. Resolving this paradox and understanding how a single gene can exhibit both oncogenic and tumor-suppressive properties is essential for successful drug targeting of RUNX. We propose a simple explanation for the duality of RUNX3: p53 status. In this model, p53 deficiency causes RUNX3 to become an oncogene, resulting in aberrant upregulation of MYC.

• Bulletin of the Korean Chemical Society
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• 제13권5호
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• pp.482-486
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• 1992

Ion-molecule reactions of acetylene and mixed acetylene-ammonia cluster ions are studied using an electron impact time-of-flight mass spectrometer. The present results clearly demonstrate that $(C_2H_2)_n^+$ cluster ion distribution represents a distinct magic number of n=3. The mass spectroscopic evidence for the enhanced structural stabilities of $[C_6H_4{\cdot}(NH_3)_m]^+$ (m=0-8) ions is also found along with the detection of mixed cluster $[(C_2H_2)_n{\cdot}(NH_3)_m]^+$ ions, which gives insight into the feasible structure of solvated ions. This is rationalized on the basis of the structural stability for acetylene clusters and the dissociation dynamics of the complex ion under the presence of solvent molecules.

• Mycobiology
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• 제49권2호
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• pp.183-187
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• 2021

The Shine Muscat is a table grape, popular in South Korea for its unique mango-flavor taste. Flyspeck is a disease that is characterized by small, black, and circular specks on the grape cuticle was first observed in several commercial orchards in Sangju, South Korea, in August 2019. Here we identified the causal agent of flyspeck based on an advanced diagnosis approach, comprised of both morphological and molecular analyses. Morphological characteristics of the cultures isolated from grape flyspeck were identical to the fungus Cladosporium perangustum. The concatenated sequences of ITS, ACT, and EF1-α were used for molecular phylogenetic analysis, BLAST searches along with Bayesian inference-based phylogeny, confirmed that the causal agent of grape flyspeck is C. perangustum. The cultured fungal isolates also produced flyspeck symptoms on healthy fruits in pathogenicity tests. To the best of my knowledge, this is the first documented evidence of any Cladosporium sp. producing flyspeck symptoms on any plant.

• 천문학회보
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• 제41권2호
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• pp.39.2-40
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• 2016

The molecular gas surrounding an H II region is thought to be a place where star formation can be induced. Such triggered star formation can arise form the overpressurization of existing density enhancements or thought the collapse of a swept up layers of material. In this talk, We will discuss the results of a study of star-formation activity associated with the outer Galaxy ring-shaped H II regions KR 7, KR 81, KR 120 and KR 140 using archival Spitzer and WISE data along with the JHK observations. We used CO data cubes from the FCRAO and TRAO in order to define extent of the molecular cloud associated each HII region. Using the infrared data sets, We identified and classified YSO populations within each molecular cloud using measures such as the class I/II ratio and YSO spatial density. Along with this, one of the main question in the study of star formation is how protostar accrete material from their parent molecular clouds and observations of infall motions are needed to provide direct evidence for accretion. Combining our observation of the YSO population distribution with time scales associated with YSO evolution and HII expansion, we investigated the possible significance of triggered star formation in the molecular cloud surrounding each region.

• 천문학회보
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• 제42권2호
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• pp.75.1-75.1
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• 2017

Ram pressure due to the intracluster medium (ICM) is known to play a crucial role in removing the cool gas content of a galaxy on a short timescale, potentially driving a star forming galaxy to evolve into a red passive population. Although many HI imaging studies find clear evidence of diffuse atomic gas stripping from cluster galaxies, it is still debatable whether the ram pressure can also strip dense molecular gas. NGC 4522, a Virgo spiral, undergoing strong ram pressure stripping, is one of the few cases where extraplanar CO emission together with stripped HI gas and $H{\alpha}$ knots has been identified, providing an ideal laboratory to study the molecular gas stripping event and the extraplanar star formation activity. The aim of this work is to investigate the origin of extraplanar molecular clouds near NGC 4522 (e.g. stripped or forming in situ), and to probe a relation between the molecular gas surface density and the star formation rate (i.e. the Kennicutt-Schmidt law) at sub-kpc scale, especially in the extraplanar space, using ALMA Cycle 3 CO data and $H{\alpha}$ data of NGC 4522. We present the results from our ALMA observations, and discuss possible scenarios for the origin of extraplanar molecular clouds and to characterize the star formation activity associated with stripped gas outside the galactic disk.

• BMB Reports
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• 제35권1호
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• pp.7-18
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• 2002

The major function of the thymus is to eliminate developing thymocytes that are potentially useless or autoreactive, and select only those that bear functional T cell antigen receptors (TCRs) through fastidious screening. It is believed that glucocorticoids (GCs) are at least in part responsible for cell death during death by neglect. In this review, we will mainly cover the topic of the GC-induced apoptosis of developing thymocytes. We will also discuss how thymocytes that are fated to die by GCs can be rescued from GC-induced apoptosis in. response to a variety of signals with antagonizing properties for GC receptor (GR) signaling. Currently, a lot of evidence supports the notion that the decision is made as a result of the integration of the multiple signal transduction networks that are triggered by GR, TCR, and Notch. A few candidate molecules at the converging point of these multiple signaling pathyways will be discussed. We will particularly describe the role of the SRG3 protein as a potent modulator of GC-induced apoptosis in the crosstalk.

• ALGAE
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• 제27권3호
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• pp.155-173
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• 2012

Evidence from molecular data supports the close taxonomic relationship of the two North Pacific species Delesseria decipiens and D. serrulata with Cumathamnion, up to now a monotypic genus known only from northern California, rather than with D. sanguinea, the type of the genus Delesseria and known only from the northeastern North Atlantic. The transfers of D. decipiens and D. serrulata into Cumathamnion are effected. Molecular data also reveal that what has passed as Membranoptera alata in the northwestern North Atlantic is distinct at the species level from northeastern North Atlantic (European) material; M. alata has a type locality in England. Multiple collections of Membranoptera and Pantoneura fabriciana on the North American coast of the North Atlantic prove to be identical for the three markers that have been sequenced, and the name Membranoptera fabriciana (Lyngbye) comb. nov. is proposed for them. Many collections of Membranoptera from the northeastern North Pacific (predominantly British Columbia), although representing the morphologies of several species that have been previously recognized, are genetically assignable to a single group for which the oldest name applicable is M. platyphylla.