• Title/Summary/Keyword: biological pathways

Search Result 704, Processing Time 0.023 seconds

Antagonistic Regulation of Arabidopsis Growth by Brassinosteroids and Abiotic Stresses

  • Chung, Yuhee;Kwon, Soon Il;Choe, Sunghwa
    • Molecules and Cells
    • /
    • v.37 no.11
    • /
    • pp.795-803
    • /
    • 2014
  • To withstand ever-changing environmental stresses, plants are equipped with phytohormone-mediated stress resistance mechanisms. Salt stress triggers abscisic acid (ABA) signaling, which enhances stress tolerance at the expense of growth. ABA is thought to inhibit the action of growth-promoting hormones, including brassinosteroids (BRs). However, the regulatory mechanisms that coordinate ABA and BR activity remain to be discovered. We noticed that ABA-treated seedlings exhibited small, round leaves and short roots, a phenotype that is characteristic of the BR signaling mutant, brassinosteroid insensitive1-9 (bri1-9). To identify genes that are antagonistically regulated by ABA and BRs, we examined published Arabidopsis microarray data sets. Of the list of genes identified, those upregulated by ABA but downregulated by BRs were enriched with a BRRE motif in their promoter sequences. After validating the microarray data using quantitative RT-PCR, we focused on RD26, which is induced by salt stress. Histochemical analysis of transgenic Arabidopsis plants expressing RD26pro:GUS revealed that the induction of GUS expression after NaCl treatment was suppressed by co-treatment with BRs, but enhanced by co-treatment with propiconazole, a BR biosynthetic inhibitor. Similarly, treatment with bikinin, an inhibitor of BIN2 kinase, not only inhibited RD26 expression, but also reduced the survival rate of the plant following exposure to salt stress. Our results suggest that ABA and BRs act antagonistically on their target genes at or after the BIN2 step in BR signaling pathways, and suggest a mechanism by which plants fine-tune their growth, particularly when stress responses and growth compete for resources.

Characterization of UV-Inducible Gene(UVI-155) in Schizosaccharomyces pombe (효모 Schizosaccharomyces pombe에서 자외선 유도유전자 UVI-155의 분리 및 특성 연구)

  • Jin, Ji-Young;Choi, In-Soon
    • Journal of Life Science
    • /
    • v.16 no.1
    • /
    • pp.126-130
    • /
    • 2006
  • The present study intends to characterize the DNA damage-inducible responses in yeast. The fission yeast, Schizosaccharomyces pombe was used in this study as a model system for higher eukaryotes. To study UV-inducible responses in S. pombe, five UV-inducible cDNA clones were isolated from S. pombe by using subtration hybridization method. To investigate the expression of isolated genes, UVI-155, the cellular levels of the transcripts were determined by Northern blot analysis after UV-irradiation. The transcripts of isolated gene (UVI-155) increased rapidly and reached maximum accumulation after UV-irradiation. Compared to the message levels of control, the levels of maximal increase were approximately 5 fold to UV-irradiation. In order to investigation whether the increase of UVI-l55 trascripts was a specific results of UV-irradiation, UVI-155 transcript levels were examined after treating the cells to mthylmethane sulfonate (MMS). The transcripts of UVI-155 were not induced by treatment of $0.25\%$ MMS. These results implied that the effects of damaging agents are complex and different regulatory pathways exist for the induction of these genes. To characterize the UVI-155 gene, gene deletion experiments were analyzed. The deleted strain was not well grown. This result indicated that the UVI-155 gene is essential for cell viability.

Antibacterial Mode of Action of Cinnamomum verum Bark Essential Oil, Alone and in Combination with Piperacillin, Against a Multi-Drug-Resistant Escherichia coli Strain

  • Yap, Polly Soo Xi;Krishnan, Thiba;Chan, Kok-Gan;Lim, Swee Hua Erin
    • Journal of Microbiology and Biotechnology
    • /
    • v.25 no.8
    • /
    • pp.1299-1306
    • /
    • 2015
  • This study aims to investigate the mechanism of action of the cinnamon bark essential oil (CB), when used singly and also in combination with piperacillin, for its antimicrobial and synergistic activity against beta-lactamase TEM-1 plasmid-conferred Escherichia coli J53 R1. Viable count of bacteria for this combination of essential oil and antibiotic showed a complete killing profile at 20 h and further confirmed its synergistic effect by reducing the bacteria cell numbers. Analysis on the stability of treated cultures for cell membrane permeability by CB when tested against sodium dodecyl sulfate revealed that the bacterial cell membrane was disrupted by the essential oil. Scanning electron microscopy observation and bacterial surface charge measurement also revealed that CB causes irreversible membrane damage and reduces the bacterial surface charge. In addition, bioluminescence expression of Escherichia coli [pSB1075] and E. coli [pSB401] by CB showed reduction, indicating the possibility of the presence of quorum sensing (QS) inhibitors. Gas-chromatography and mass spectrometry of the essential oil of Cinnamomum verum showed that trans-cinnamaldehyde (72.81%), benzyl alcohol (12.5%), and eugenol (6.57%) were the major components in the essential oil. From this study, CB has the potential to reverse E. coli J53 R1 resistance to piperacillin through two pathways; modification in the permeability of the outer membrane or bacterial QS inhibition.

Transcriptomic analysis of the liver in aged laying hens with different intensity of brown eggshell color

  • Han, Gi Ppeum;Kim, Jun-Mo;Kang, Hwan Ku;Kil, Dong Yong
    • Animal Bioscience
    • /
    • v.34 no.5
    • /
    • pp.811-823
    • /
    • 2021
  • Objective: Eggshell color is an important indicator of egg quality for consumers, especially for brown eggs. Various factors related to laying hens and their environment affect brown eggshell coloration. However, there have been no studies investigating hepatic functions of laying hens with variable intensity of brown eggshell color. Therefore, this study was aimed to identify potential factors affecting brown eggshell coloration in aged laying hens at the hepatic transcriptomic level. Methods: Five hundred 92-wk-old Hy-line Brown laying hens were screened to select laying hens with different intensity of brown eggshell color based on eggshell color fans. Based on eggshell color scores, hens with dark brown eggshells (DBE; eggshell color fan score = 14.8) and hens with light brown eggshells (LBE; eggshell color fan score = 9.7) were finally selected for the liver sampling. We performed RNA-seq analysis using the liver samples through the paired-end sequencing libraries. Differentially expressed genes (DEGs) profiling was carried out to identify their biological meaning by bioinformatics. Results: A total of 290 DEGs were identified with 196 being up-regulated and 94 being down-regulated in DBE groups as compared to LBE groups. The Kyoto encyclopedia of genes and genomes (KEGG) analysis revealed that these DEGs belong to several biological pathways including herpes simplex infection (toll-like receptor 3 [TLR3], cyclin-dependent kinase 1, etc.) and influenza A (TLR3, radical S-adenosyl methionine domain containing 2, myxovirus [influenza virus] resistance 1, etc.). Genes related to stress response (ceremide kinase like) and nutrient metabolism (phosphoenolpyruvate carboxy-kinase 1, methylmalonic aciduria [cobalamin deficiency] cblB type, glycine receptor alpha 2, solute carrier family 7 member 11, etc.) were also identified to be differentially expressed. Conclusion: The current results provide new insights regarding hepatic molecular functions related to different intensity of brown eggshell color in aged laying hens. These insights will contribute to future studies aiming to optimize brown eggshell coloration in aged laying hens.

Application of Dynamic Regulation to Increase L-Phenylalanine Production in Escherichia coli

  • Wu, Jie;Liu, Yongfei;Zhao, Sheng;Sun, Jibin;Jin, Zhaoxia;Zhang, Dawei
    • Journal of Microbiology and Biotechnology
    • /
    • v.29 no.6
    • /
    • pp.923-932
    • /
    • 2019
  • Current strategies of strain improvement processes are mainly focused on enhancing the synthetic pathways of the products. However, excessive metabolic flux often creates metabolic imbalances, which lead to growth retardation and ultimately limit the yield of the product. To solve this problem, we applied a dynamic regulation strategy to produce $\text\tiny{L}$-phenylalanine ($\text\tiny{L}$-Phe) in Escherichia coli. First, we constructed a series of Phe-induced promoters that exhibited different strengths through modification of the promoter region of tyrP. Then, two engineered promoters were separately introduced into a Phe-producing strain xllp1 to dynamically control the expression level of one pathway enzyme AroK. Batch fermentation results of the strain xllp3 showed that the titer of Phe reached 61.3 g/l at 48 h, representing a titer of 1.36-fold of the strain xllp1 (45.0 g/l). Moreover, the $\text\tiny{L}$-Phe yields on glucose of xllp3 (0.22 g/g) were also greatly improved, with an increase of 1.22-fold in comparison with the xllp1 (0.18 g/g). In summary, we successfully improved the titer of Phe by using dynamic regulation of one key enzyme and this strategy can be applied for improving the performance of strains producing other aromatic amino acids and derived compounds.

Bioconversion of Gentiana scabra Bunge increases the anti-inflammatory effect in RAW 264.7 cells via MAP kinases and NF-κB pathway

  • Kim, Min-A;Lee, Han-Saem;Chon, So-Hyun;Park, Jeong-Eun;Lim, Yu-Mi;Kim, Eun-Jeong;Son, Eun-Kyung;Kim, Sang-Jun;So, Jai-Hyun
    • Journal of Applied Biological Chemistry
    • /
    • v.62 no.1
    • /
    • pp.39-50
    • /
    • 2019
  • Mitogen-activated protein (MAP) kinases play an important role in cell growth and differentiation, as well as the modulation of proinflammatory cytokines. The objective of this study was to examine the increase in the anti-inflammatory effect of Gentiana scabra Bunge (GSB), due to bioconversion with the Aspergillus kawachii crude enzyme, via inhibition of the $NF-{\kappa}B$ signaling and MAP kinase pathways in RAW 264.7 cells. The expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 in RAW 264.7 cells treated with the GSB ethyl acetate fraction bioconverted with A. kawachii crude enzyme (GE-BA), was dramatically suppressed as compared to GSB ethyl acetate fraction non-bioconverted with the A. kawachii crude enzyme (GE-UA). The phosphorylation of p38, extracellular signal-regulated kinases, and inhibitory ${\kappa}B$ in RAW 264.7 cells treated with GE-BA was further suppressed, as compared to exposure to GE-UA. Moreover, the mRNA expression of interleukin 6, interleukin 1-beta, and tumor necrosis $factor-{\alpha}$ was further suppressed by GE-BA, compared to GE-UA. Similarly, anti-oxidant activities, such as 2,2-diphenyl-1-picrylhydrazyl hydrate and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activity, of GE-BA were further increased compared to GE-UA. These observations demonstrate that the anti-oxidant and anti-inflammatory activities of GSB ethyl acetate fraction increases as a result from bioconversion with the A. kawachii crude enzyme.

Myonectin inhibits adipogenesis in 3T3-L1 preadipocytes by regulating p38 MAPK pathway

  • Park, Tae-Jun;Park, Anna;Kim, Jaehoon;Kim, Jeong-Yoon;Han, Baek Soo;Oh, Kyoung-Jin;Lee, Eun Woo;Lee, Sang Chul;Bae, Kwang-Hee;Kim, Won Kon
    • BMB Reports
    • /
    • v.54 no.2
    • /
    • pp.124-129
    • /
    • 2021
  • In current times, obesity is a major health problem closely associated with metabolic disease such as diabetes, dyslipidemia, and cardiovascular disease. The direct cause of obesity is known as an abnormal increase in fat cell size and the adipocyte pool. Hyperplasia, the increase in number of adipocytes, results from adipogenesis in which preadipocytes differentiate into mature adipocytes. Adipogenesis is regulated by local and systemic cues that alter transduction pathways and subsequent control of adipogenic transcription factors. Therefore, the regulation of adipogenesis is an important target for preventing obesity. Myonectin, a member of the CTRP family, is a type of myokine released by skeletal muscle cells. Although several studies have shown that myonectin is associated with lipid metabolism, the role of myonectin during adipogenesis is not known. Here, we demonstrate the role of myonectin during adipocyte differentiation of 3T3-L1 cells. We found that myonectin inhibits the adipogenesis of 3T3-L1 preadipocytes with a reduction in the expression of adipogenic transcription factors such as C/EBPα, β and PPARγ. Furthermore, we show that myonectin has an inhibitory effect on adipogenesis through the regulation of the p38 MAPK pathway and CHOP. These findings suggest that myonectin may be a novel therapeutic target for the prevention of obesity.

Identification of Subgroups with Poor Glycemic Control among Patients with Type 2 Diabetes Mellitus: Based on the Korean National Health and Nutrition Examination Survey from KNHANES VII (2016 to 2018) (제 2형 성인 당뇨병 유병자의 혈당조절 취약군 예측: 제7기(2016-2018년도) 국민건강영양조사 자료 활용)

  • Kim, Hee Sun;Jeong, Seok Hee
    • Journal of Korean Biological Nursing Science
    • /
    • v.23 no.1
    • /
    • pp.31-42
    • /
    • 2021
  • Purpose: This study was performed to assess the level of blood glucose and to identify poor glycemic control groups among patients with type 2 diabetes mellitus (DM). Methods: Data of 1,022 Korean type 2 DM patients aged 30-64 years were extracted from the Korea National Health and Nutrition Examination Survey VII. Complex samples analysis and a decision-tree analysis were performed using the SPSS WIN 26.0 program. Results: The mean level of hemoglobin A1c (HbA1c) was 7.22±0.25%, and 69.0% of the participants showed abnormal glycemic control (HbA1c≥6.5%). The characteristics of participants associated with poor glycemic control groups were presented with six different pathways by the decision-tree analysis. Poor glycemic control groups were classified according to the patients' characteristics such as period after DM diagnosis, awareness of DM, sleep duration, gender, alcohol drinking, occupation, income status, low density lipoprotein-cholesterol, abdominal obesity, and number of walking days per week. Period of DM diagnosis with a cut-off point of 6 years was the most significant predictor of the poor glycemic control group. Conclusion: The findings showed the predictable characteristics of the poor glycemic control groups, and they can be used to screen the poor glycemic control groups among adults with type 2 DM.

Anti-inflammatory and antioxidant effects of Barringtonia augusta Kurz extract (Barringtonia augusta Kurz 추출물의 항염증 및 항산화 효능 평가)

  • Ryu, Soo Ho;Kim, Min Jeong;Bach, Tran The;Jung, Sung Keun
    • Korean Journal of Food Science and Technology
    • /
    • v.53 no.2
    • /
    • pp.154-159
    • /
    • 2021
  • Barringtonia augusta Kurz is a species of the genus Barringtonia. Although several studies have analyzed the biological activity of B. racemosa Roxb and B. acutangula, the anti-inflammatory and antioxidant effects of B. augusta extract (BKE) remain unclear. Therefore, in this study, we investigated the anti-inflammatory and antioxidant effects of BKE using lipopolysaccharide (LPS) and RAW 264.7. BKE suppressed LPS-induced nitric oxide (NO) and inducible NO synthase expression without affecting RAW 264.7 cell viability. Additionally, BKE showed 2,2-Diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging capacities and inhibited LPS-induced reactive oxygen species production in RAW 264.7 cells. BKE also suppressed LPS-induced phosphorylation of IκB kinase and nuclear factor kappa-B (NF-κB) and p65 translocation from the cytosol to the nucleus in RAW 264.7 cells. These results suggest that BKE is a possible novel material that exerts beneficial antioxidant and anti-inflammatory effects through the inhibition of NF-κB signaling pathways.

Association between cancer metabolism and muscle atrophy (암 대사와 근위축의 연관성)

  • Yeonju Seo;Ju-Ock Nam
    • Journal of Applied Biological Chemistry
    • /
    • v.65 no.4
    • /
    • pp.387-396
    • /
    • 2022
  • Skeletal muscle accounts for about 40-50% of body weight and is an important tissue that performs various functions, such as maintaining posture, supporting soft tissues, maintaining body temperature, and respiration. Cancer, which occurs widely around the world, causes cancer cachexia accompanied by muscular atrophy, which reduces the effectiveness of anticancer drugs and greatly reduces the quality of life and survival rate of cancer patients. Therefore, research to improve cancer cachexia is ongoing. However, there are few studies on the link between cancer and muscle atrophy. Cancer cells exhibit distinct microenvironment and metabolism from tumor cells, including tumor-associated macrophages (TAM), tumor-associated neutrophils (TAN), and insulin resistance due to the Warburg effect. Therefore, we summarize the microenvironment and metabolic characteristics of cancer cells, and the molecular mechanisms of muscle atrophy that can be affected by cytokine and insulin resistance. In addition, this suggests the possibility of improving cancer cachexia of substances affecting TAM, TAN, and Warburg effect. We also summarize the mechanisms identified so far through single agents and the signaling pathways mediated by them that may ameliorate cancer cachexia.