• Title/Summary/Keyword: K-Ras

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Phosphorylation of SAV1 by mammalian ste20-like kinase promotes cell death

  • Park, Byoung-Hee;Lee, Yong-Hee
    • BMB Reports
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    • v.44 no.9
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    • pp.584-589
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    • 2011
  • The mammalian ste20-like kinase (MST) pathway is important in the regulation of apoptosis and cell cycle and emerges as a novel tumor suppressor pathway. MST-induced phosphorylation of Salvador homolog 1 (SAV1), which is a scaffold protein, has not been evaluated in detail. We performed a mass spectrometric analysis of the SAV1 protein that was co-expressed with MST2. Phosphorylation was detected at Thr-26, Ser-27, Ser-36 and Ser-269. Although single or double mutations had little effects, the mutation of all four residues in SAV1 to Ala (SAV1-4A) had inhibitory effects on the MST pathway. MST2-mediated induction of SAV1-4A protein levels, SAV1-4A interaction with MST2 and the self-dimerization of SAV1-4A were weaker compared to those of wild-type SAV1. SAV1-4A inhibited MST2- and K-RasG12V-induced cell death of MCF7 cells. These results suggest that MST-mediated phosphorylation of four residues within SAV1 may be important in the induction of cell death by the MST pathway.

Spatiotemporal variations and source apportionment of NOx, SO2, and O3 emissions around heavily industrial locality

  • Al-Harbi, Meshari;Al-majed, Abdulrahman;Abahussain, Asma
    • Environmental Engineering Research
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    • v.25 no.2
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    • pp.147-162
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    • 2020
  • The main objective of this study is to estimate the levels of pollution to which the community is presently exposed and to model the regimes of local air quality. Diurnal, daily, and monthly variations of NO, NO2, SO2, and O3 were thoroughly investigated in three areas; namely, residential, industrial, and terminal in Ras Al-Khafji. There is obvious diurnal variation in the concentration of these pollutants that clearly follows the diurnal variation of atmospheric temperature and main anthropogenic and industrial activities. Correlation analysis showed that meteorological conditions play a vital role in shaping the pattern and transportation of air pollutants and photochemical processes affecting O3 formation and destruction. Bivariate polar plots, an effective graphical tool that utilizes air pollutant concentrations' dependence on wind speed and wind direction, were used to identify prevailing emission sources. Non-buoyant ground-level sources like domestic heating and street transport emissions, various industrial stacks, and airport-related activities were considered dominant emission sources in observatory sites. This study offers valuable and detailed information on the status of air quality, which has considerable, quantifiable, and important public health benefits.

Connecting the dots between SHP2 and glutamate receptors

  • Ryu, Hyun-Hee;Kim, Sun Yong;Lee, Yong-Seok
    • The Korean Journal of Physiology and Pharmacology
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    • v.24 no.2
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    • pp.129-135
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    • 2020
  • SHP2 is an unusual protein phosphatase that functions as an activator for several signaling pathways, including the RAS pathway, while most other phosphatases suppress their downstream signaling cascades. The physiological and pathophysiological roles of SHP2 have been extensively studied in the field of cancer research. Mutations in the PTPN11 gene which encodes SHP2 are also highly associated with developmental disorders, such as Noonan syndrome (NS), and cognitive deficits including learning disabilities are common among NS patients. However, the molecular and cellular mechanism by which SHP2 is involved in cognitive functions is not well understood. Recent studies using SHP2 mutant mice or pharmacological inhibitors have shown that SHP2 plays critical role in learning and memory and synaptic plasticity. Here, we review the recent studies demonstrating that SHP2 is involved in synaptic plasticity, and learning and memory, by the regulation of the expression and/or function of glutamate receptors. We suggest that each cell type may have distinct paths connecting the dots between SHP2 and glutamate receptors, and these paths may also change with aging.

Basic Survey for Evaluation of Instream flow at Natural Recovery Reach (자연형 하천 복원구간의 하천유지유량 산정을 위한 기초조사)

  • Sea, Kyu-Woo;Woo, Sang-Hwan;Kim, Gwang-Seob
    • Journal of Wetlands Research
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    • v.3 no.2
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    • pp.119-131
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    • 2001
  • This study uses HEC-RAS for the quantitative aspects and the QUAL2E model for the qualitative aspects of the flow of urban streams, where the natural recovery system is applied. The instream flow of the small streams is estimated using the numerical model by verifying the existing data with the acquired data. The characteristics of the model reach place more weight on the drought discharge around the ordinary discharge, and this is caused by the natural recovery system that maintains the existing bank. The data of direct discharge to the sewage treatment plant through the inception pipe, BOD, DO, temperature, and so forth, are the official data from the department of environment. Considering the characteristics of small streams, the factors for the QUAL2E model are estimated with the focus on the hydraulic conditions and the stream view. This study proposes the future improvements for the natural recovery system by investigating the practical use of the waterfront and the application of the proper instream flow. Also, the hydraulic and hydrological investigation of the covering rate by the natural vegetation and the meandering by the varying river way is performed.

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Association between Angiotensin I-Converting Enzyme Gene Polymorphism and Hypertension in Selected Individuals of the Bangladeshi Population

  • Morshed, Mahboob;Khan, Haseena;Akhteruzzaman, Sharif
    • BMB Reports
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    • v.35 no.3
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    • pp.251-254
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    • 2002
  • The genetic factors that contribute to the development of coronary artery disease (CAD) are poorly understood. It is likely that multiple genes that act independently or synergistically contribute to the development of CAD and the outcome. Recently, an insertion/deletion (I/D) polymorphism of the human angiotensin I-converting enzyme (ACE) gene, a major component of the renin-angiotensin system (RAS), was identified. The association of the ACE gene D allele with essential hypertension and CAD has been reported in the African-American, Chinese, and Japanese populations. However, other studies have failed to detect such an association. It has been suggested that these inconsistencies may be due to the difference in backgrounds of the population characteristics. In the present study, we investigated the I/D polymorphism of the ACE gene in 103 subjects of both sexes, consisting of 59 normal controls and 44 patients with hypertension. The allele and genotype frequency were significantly different between the hypertensive and control groups (p < 0.01). Among the three ACE I/D variants, the DD genotype was associated with the highest value of the mean systolic blood pressure [SBP] and mean diastolic blood pressure [DBP] (p = < 0.05) in men, but not in women. In the overall population, the mean SBP and DBP was highest in DD subjects, intermediate in I/D subjects, and the least in II subjects.

Influence of Different Feeding Frequency on the Growth and Body Composition of Juvenile Mandarin Fish Siniperca scherzeri Reared in a Recirculating Aquaculture System (RAS) (사료 공급 횟수가 쏘가리(Siniperca scherzeri) 치어의 성장 및 체조성에 미치는 영향)

  • Kim, Yi-Oh;Oh, Sung-Yong;Lee, Sang-Min
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.53 no.4
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    • pp.538-543
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    • 2020
  • A feeding trial was conducted to investigate the effect of feeding frequency on the growth performance and body composition of juvenile mandarin fish Siniperca scherzeri. Triplicate groups of fish (initial fish weight, 7.5 g/fish) were fed to apparent satiation at one, two, three or four meals per day for 8 weeks. The results showed that weight gain of fish fed one meal per day was significantly (P<0.05) lower than those fish fed two, three or four meals per day. Feed efficiency of fish fed two meals per day was significantly (P<0.05) higher than other experimental groups. The plasma cholesterol content was significantly lower in fish fed one meal per day than those fed two, three or four meals per day. Consequently, we can conclude that feeding juvenile mandarin fish twice daily to apparent satiation is acceptable and sufficient to achieve good growth and feed efficiency, as fish performance was not remarkably enhanced when feeding increased from two to four times per day.

Biomarkers for the lung cancer diagnosis and their advances in proteomics

  • Sung, Hye-Jin;Cho, Je-Yoel
    • BMB Reports
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    • v.41 no.9
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    • pp.615-625
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    • 2008
  • Over a last decade, intense interest has been focused on biomarker discovery and their clinical uses. This interest is accelerated by the completion of human genome project and the progress of techniques in proteomics. Especially, cancer biomarker discovery is eminent in this field due to its anticipated critical role in early diagnosis, therapy guidance, and prognosis monitoring of cancers. Among cancers, lung cancer, one of the top three major cancers, is the one showing the highest mortality because of failure in early diagnosis. Numerous potential DNA biomarkers such as hypermethylations of the promoters and mutations in K-ras, p53, and protein biomarkers; carcinoembryonic antigen (CEA), CYFRA21-1, plasma kallikrein B1 (KLKB1), Neuron-specific enolase, etc. have been discovered as lung cancer biomarkers. Despite extensive studies thus far, few are turned out to be useful in clinic. Even those used in clinic do not show enough sensitivity, specificity and reproducibility for general use. This review describes what the cancer biomarkers are for, various types of lung cancer biomarkers discovered at present and predicted future advance in lung cancer biomarker discovery with proteomics technology.

Spry2 does not directly modulate Raf-1 kinase activity in v-Ha-ras-transformed NIH 3T3 fibroblasts

  • Ahn, Jun-Ho;Eum, Ki-Hwan;Lee, Michael
    • BMB Reports
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    • v.43 no.3
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    • pp.205-211
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    • 2010
  • Sprouty (Spry) proteins have previously been suggested as negative regulators of the MAPK pathway through interaction with Raf-1. However, the molecular basis of this inhibition has not been elucidated. In this study, we used cells expressing FLAGtagged Raf-1 with point mutations at known phosphorylation sites to reveal that activation of Raf-1 mutants does not correlate with their degree of interaction with Spry2. The association of Raf-1 with Spry2 in intact cells was further corroborated by immunofluorescence colocalization. Additionally, there was no significant change observed in the strength of interaction between Raf-1 mutants and Spry2 after paclitaxel treatment despite differences in the activation levels of these mutants. Thus, our study provides the evidence that Spry2 does not directly regulate Raf-1 kinase activity, but instead acts as a scaffolding protein that assists interactions between Raf-1 kinase and its direct regulators.

Expression of Wee1 Gene in the Ascidian, Halocynthia roretzi Embryo

  • Lee, Won-Young;Ham, Hwa-Su;Kim, Gil-Jung
    • Development and Reproduction
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    • v.15 no.1
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    • pp.1-7
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    • 2011
  • It is suggested that FGF/Ras/MEK/Erk signaling plays crucial roles in specification and cell division of the mesodermal precursor cells in ascidian embryos. To investigate how the number of cell division in tissue precursor cells is determined, we have characterized Wee1 homolog, Hr-Wee1 of the ascidian Halocynthia roretzi. We found that the Hr-Wee1 mRNA is expressed both maternally and zygotically. Maternal transcript is localized to the cytoplasm in the animal cells, while zygotic expression is seen in cells of the endoderm lineage from 32-cell to 110-cell stages. Zygotic in situ signal is detected in the A-line neural plate cells of neurulae, and in epidermal cells of the head region of tailbud embryos. Embryos treated with MEK signaling inhibitor showed a similar pattern to normal embryos in expression of Hr-Wee1. Therefore, it is likely that MEK signaling does not affect the maternal and zygotic expression of Hr-Wee1.

A 2-D numerical research on spatial variability of concrete carbonation depth at meso-scale

  • Pan, Zichao;Ruan, Xin;Chen, Airong
    • Computers and Concrete
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    • v.15 no.2
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    • pp.231-257
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    • 2015
  • This paper discusses the spatial variability of the carbonation depth caused by the mesoscopic structure of the concrete and the influence of the spatial variability on the thickness of the concrete cover. To conduct the research, a method to generate the random aggregate structure (RAS) based on polygonal particles and a simplified numerical model of the concrete carbonation at meso-scale are firstly developed. Based on the method and model, the effect of the aggregate properties including shape, content and gradation on the spatial variability of the carbonation depth is comprehensively studied. The results show that a larger degree of the spatial variability will be obtained by using (1) the aggregates with a larger aspect ratio; (2) a larger aggregate content; (3) the gradation which has more large particles. The proper sample size and model size used in the analysis are also studied. Finally, a case study is conducted to demonstrate the influence of the spatial variability of the carbonation depth on the proper thickness of the concrete cover. The research in this paper not only provides suggestions on how to decrease the spatial variability, but also proposes the method to consider the effect of the spatial variability in designing the thickness of the concrete cover.