• Title/Summary/Keyword: signal molecule

Search Result 155, Processing Time 0.02 seconds

DETECTABILITY OF $H_2$-Ar AND $H_2$-Ne DIMERS IN JOVIAN ATMOSPHERES

  • 민영기;김상준;김용호;이용식
    • Journal of Astronomy and Space Sciences
    • /
    • v.14 no.2
    • /
    • pp.251-258
    • /
    • 1997
  • The detection of jovian hydrogen-hydrogen dimers through the clear telluric 2-micron window(Kim et al. 1995, Trafton et al. 1997( suggests possibility to detect noble gases in the form of dimer with hydrogen in jovian atmospheres. Since noble noble gases do not have spectral structures in the infrared, it has been difficult to derive their abundances in the atmospheres of jovian planets. If there is a significant component of noble gases other than helium in the jovian atmospheres. it might be detected through its dimer spectrum with hydrogen molecule. The relatively sharp spectral structures of hydrogen-argon and hydrogen-neon dimers compared with those of hydrogen-hydrogen dimers are useful for the detection, if an adequate signal-to-noise (S/N) is obtained. If we use a large telescope, such as the Keck telescope, with a long exposure time (>24 hours), then $H_2-Ar$ spectral structure may be detected.

  • PDF

Nitric Oxide Plays an Important Role in β-Aminobutyric Acid-Induced Resistance to Botrytis cinerea in Tomato Plants

  • Li, Rui;Sheng, Jiping;Shen, Lin
    • The Plant Pathology Journal
    • /
    • v.36 no.2
    • /
    • pp.121-132
    • /
    • 2020
  • β-Aminobutyric acid (BABA) has consistently been reported to enhance plant immunity. However, the specific mechanisms and downstream components that mediate this resistance are not yet agreed upon. Nitric oxide (NO) is an important signal molecule involved in a diverse range of physiological processes, and whether NO is involved in BABA-induced resistance is interesting. In this study, treatment with BABA significantly increased NO accumulation and reduced the sensitivity to Botrytis cinerea in tomato plants. BABA treatment reduced physical signs of infection and increased both the transcription of key defense marker genes and the activity of defensive enzymes. Interestingly, compared to treatment with BABA alone, treatment with BABA plus cPTIO (NO specific scavenger) not only significantly reduced NO accumulation, but also increased disease incidence and lesion area. These results suggest that NO accumulation plays an important role in BABA-induced resistance against B. cinerea in tomato plants.

Nonstructural Protein 5B of Hepatitis C Virus

  • Lee, Jong-Ho;Nam, In Young;Myung, Heejoon
    • Molecules and Cells
    • /
    • v.21 no.3
    • /
    • pp.330-336
    • /
    • 2006
  • Since its identification in 1989, hepatitis C virus has been the subject of extensive research. The biology of the virus and the development of antiviral drugs are closely related. The RNA polymerase activity of nonstructural protein 5B was first demonstrated in 1996. NS5B is believed to localize to the perinuclear region, forming a replicase complex with other viral proteins. It has a typical polymerase structure with thumb, palm, and finger domains encircling the active site. A de novo replication initiation mechanism has been suggested. To date, many small molecule inhibitors are known including nucleoside analogues, non-nucleoside analogues, and pyrophosphate mimics. NS5B interacts with other viral proteins such as core, NS3, 4A, 4B, and 5A. The helicase activity of NS3 seems necessary for RNA strand unwinding during replication, with other nonstructural proteins performing modulatory roles. Cellular proteins interacting with NS5B include VAMP-associated proteins, heIF4AII, hPLIC1, nucleolin, PRK2, ${\alpha}$-actinin, and p68 helicase. The interactions of NS5B with these proteins might play roles in cellular trafficking, signal transduction, and RNA polymerization, as well as the regulation of replication/translation processes.

Cudrania tricuspidata Suppresses Mast Cell-Mediated Allergic Response In Vitro and In Vivo (꾸지뽕나무 추출물의 비만세포 억제에 의한 항알레르기 효과 및 기전)

  • Kim, Young-Mi
    • YAKHAK HOEJI
    • /
    • v.56 no.1
    • /
    • pp.26-34
    • /
    • 2012
  • Mast cells play an important role in early and late phase allergic reactions through allergen and IgE-dependent release of histamine, proteases, prostaglandins, and several multifunctional cytokines. In this study, we investigated whether Cudrania tricuspidata extract (CTE) suppresses IgE-mediated allergic responses in mast cells, an allergic animal model, and its mechanism of action in mast cells. We found that CTE inhibited IgE-mediated degranulation and cytokine production in rat basophilic leukemia (RBL)-2H3 mast cells and bone marrow-derived mast cells (BMMC), as well as passive cutaneous anaphylaxis (PCA) in mice. With regard to its mechanism of action, CTE suppressed the activating phosphorylation of spleen tyrosine kinase (Syk), a key enzyme in mast cell signaling processes and that of LAT, a downstream adaptor molecule of Syk in $Fc{\varepsilon}RI$-mediated signal pathways. CTE also suppressed the activating phosphorylation of mitogen-activated protein (MAP) kinases and Akt. The present results strongly suggest that the anti-allergic activity of CTE is mediated through inhibiting degranulation and allergic cytokine secretion by inhibition of Syk kinase in mast cells. Therefore, CTE may be useful for the treatment of allergic diseases.

Functional Characteristics of C-terminal Lysine to Cysteine Mutant Form of CTLA-4Ig

  • Kim, Bongi;Shin, Jun-Seop;Park, Chung-Gyu
    • IMMUNE NETWORK
    • /
    • v.13 no.1
    • /
    • pp.16-24
    • /
    • 2013
  • CTLA-4Ig is regarded as an inhibitory agent of the T cell proliferation via blocking the costimulatory signal which is essential for full T cell activation. To improve applicability, we developed the CTLA-4Ig-CTKC in which the c-terminal lysine had been replaced by cysteine through single amino acid change. The single amino acid mutation of c-terminus of CTLA-4Ig was performed by PCR and was checked by in vitro transcription and translation. DNA construct of mutant form was transfected to Chinese hamster ovary (CHO) cells by electroporation. The purified proteins were confirmed by Western blot and B7-1 binding assay for their binding ability. The suppressive capacity of CTLA-4Ig-CTKC was evaluated by the mixed lymphocyte reaction (MLR) and in the allogeneic pancreatic islet transplantation model. CTLA-4Ig-CTKC maintained binding ability to B7-1 molecule and effectively inhibits T cell proliferation in MLR. In the murine allogeneic pancreatic islet transplantation, short-term treatment of CTLA-4Ig-CTKC prolonged the graft survival over 100 days. CTLA-4Ig-CTKC effectively inhibits immune response both in MLR and in allogeneic islet transplantation model, indicating that single amino acid mutation does not affect the inhibitory function of CTLA-4Ig. CTLA-4Ig-CTKC can be used in vehicle-mediated drug delivery system such as liposome conjugation.

Effects of Yangkyuksanhawtang on the Allergic Contact Dermatitis (양격산화탕(凉隔散化湯)이 Allergy성(性) 접촉피부염(接觸皮膚炎)에 미치는 영향(影響))

  • Cho, Se-Wang
    • Korean Journal of Korean Medical Institute of Dermatology and Aesthetics
    • /
    • v.1 no.1
    • /
    • pp.16-40
    • /
    • 2005
  • Objective : To study the effectiveness of Yangkyuksanhawtang against Allergic Contact Dermatitis I observed the change of cutaneous shape, histochemistry, immunohistochemistry, and the distribution of apoptotic cells. materials and methods : I divided 4-month-old rats into three groups of 10, which are a contrastive group of having applied Acetone olive oil only, ACD group to have intentionally activated Allergic Contact Dermatitis by DNCB and YST group to give medication of Yangkyuksanhawtang extract. And I observed each group of mice after 24, 48 and 72 hours. results : 1. With the result of Contact hypersensitivity assay, YST group shows appreciably less ear swelling than ACD group. 2. Comparing YST and ACD groups to each other regarding general change of skin, YST group shows less hyperplasia of epidermis, less migration of inflammatory cells and less damage of epidermis than ACD group. 3. Regarding the change of collagen fiber, ACD group has appeared to be low in number of collagen fiber while YST shows similarity with the contrastive group. 4. In dermis YST group has showed lower number of mastocyte than ACD group and is granulated type. 5. In dermis YST group has showed less MAC-1, IL-1 , $IL-2R-\;{\alpha}$ G, ICAM-1 and VCAM-1 than ACD group. 6. The distribution of apoptotic cells has appeared littler in YST group than in ACD 7. Among signal molecule of apoptosis Bcl-2 has distributed more in YST group than ACD group and Bax and Fas has distributed less in YST group than ACD group.

  • PDF

Galleria mellonella 6-Tox Gene, Putative Immune Related Molecule in Lepidoptera

  • Lee, Joon-Ha;Park, Seung-Mi;Chae, Kwon-Seok;Lee, In-Hee
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.21 no.1
    • /
    • pp.127-132
    • /
    • 2010
  • We have characterized full-length cDNA encoding Gall-6-tox protein, which was cloned from the fat body of the immunized Galleria mellonella larvae. The cloned cDNA of Gall-6-tox consists of 1301 nucleotides and contained an open reading frame of 891 nucleotides corresponding to a protein of 296 residues that includes a putative 16-residue signal sequence and a 280-residue mature peptide with a calculated mass of 30,707.73 Da. The deduced mature peptide contains conserved tandem repeats of six cysteine-stabilized alpha beta ($Cs{\alpha}{\beta}$) motifs, which was detected in scorpion toxins and insect defensins. In the sequence homology search, mature Gall-6-tox showed 34% and 28% amino acid sequence homology with Bomb-6-tox from Bombyx mori and Spod-11-tox from Spodoptera frugiperda, respectively. Gall-6-tox orthologs were only found in Lepidopteran species, indicating that this new immune-related gene family is specific to this insect order. RT-PCR analysis revealed that Gall-6-tox was expressed primarily in the larval fat bodies, hemocytes, and midgut against invading bacteria into hemocoel. Moreover, the expression time course of Gall-6-tox was examined up to 24 h in the fat bodies and midgut after injection of E. coli. Altogether, these results suggest that Gall-6-tox is derived from defensins and Gall-6-tox may play a critical role in Lepidoptera immune system.

Combined Effects of Multiple Endoplasmic Reticulum Stresses on Cytokine Secretion in Macrophage

  • Kim, Hye-Min;Do, Chang-Hee;Lee, Dong-Hee
    • Biomolecules & Therapeutics
    • /
    • v.20 no.3
    • /
    • pp.346-351
    • /
    • 2012
  • Cells show various stress signs when they are challenged with severe physiological problems. Majority of such cellular stresses are conveyed to endoplasmic reticulum (ER) and unfolded protein response (UPR) serves as typical defense mechanism against ER stress. This study investigated an interaction between ER stress agents using macropage cell line Raw 264.7. When activated by lipopolysaccharide (LPS), the cell lines showed typical indicators of ER stress. Along with molecular chaperones, the activation process leads to the production of additional inflammatory mediators. Following activation, the macrophage cell line was further treated with TUN and characterized in terms of chaperone expression and cytokine secretion. When treated with TUN, the activated macrophage cell leads to increased secretion of IL-6 although expression of ER stress markers, GRP94 and GRP78 increased. The secretion of cytokines continued until the addition of BFA which inhibits protein targeting from ER to Golgi. However, secretion of cytokines was ceased upon dual treatments with BFA and TG. This result strongly implies that cells may differently deal with various polypeptides depending on the urgency in cellular function under ER stress. Considering IL-6 is one of the most important signal molecules in macrophage, the molecule might be able to circumvent ER stress and UPR to reach its targeting site.

Effect of nitric oxide on the expression of matrix metalloproteinases by the UV irradiated human dermal fibroblasts

  • Taeboo Choe;Lee, Bumchun;Park, Inchul;Seokil Hong
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.28 no.1
    • /
    • pp.31-41
    • /
    • 2002
  • The production of matrix matalloproteinases(MMPs) by the UV irradiated skin fibroblast and the degradation of extracellular matrix(ECM) by these enzymes is known as one of the main reasons of photoaging. Recently, Fisher group showed that the MMP expression is mainly regulated by the mitogen-activated protein(MAP) kinas family, such as extracellular signal-regulated kinase(ERK), c-Jun amino-terminal kinase(JNK) and p38, each of which forms a signaling pathway. In this work we first examined the effect of nitric oxide (NO) on the production of MMP-1 and MMP-2 by the human dermal fibroblasts (HDFs). NO is a multifunctional messenger molecule generated from L-arginine and involved in many kinds of signaling pathway. We found that the treatment of HDF with NO donor, sodium nitroprusside (SNP) enhanced the expression of MMPs with or without UV irradiation and the treatment with nitric oxide synthase (NOS) inhibitors resulted in the significant decrease of MMPs production. From these results, we concluded that the production of MMPs by the UV irradiated HDF is regulated through the signaling pathway involving NO and cyclic GMP.

Spectroscopy of acetylene (13C2H2) using a tunable erbium-doped fiber ring laser (파장가변 광섬유 링 레이저를 이용한 아세틸렌(13C2H2) 분광)

  • 유한영;오정미;이동한;문한섭;이원규;박갑동;서호성
    • Korean Journal of Optics and Photonics
    • /
    • v.14 no.6
    • /
    • pp.674-679
    • /
    • 2003
  • We fabricated erbium-doped fiber ring laser with a new structure that can operate in C- & L-band wavelength region. The wave-length of the laser can be tuned continuously over 102 nm between 1510.4-1612.6 nm by insertion of the fiber Fabry-Perot tunable filter (FFP-TF) in the ring cavity. By use of the wavelength tunable characteristics of our fiber laser, we measured absorption spectra of more than fifty transition lines of the acetylene ($^{13}$ C$_2$H$_2$) molecule with high signal to noise ratio (SNR).