• 제목/요약/키워드: regulatory factor

검색결과 749건 처리시간 0.022초

Mechanisms of immune tolerance to allergens in children

  • Kucuksezer, Umut C.;Ozdemir, Cevdet;Akdis, Mubeccel;Akdis, Cezmi A.
    • Clinical and Experimental Pediatrics
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    • 제56권12호
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    • pp.505-513
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    • 2013
  • Because the prevalence of allergic diseases has significantly increased in recent years, understanding the causes and mechanisms of these disorders is of high importance, and intense investigations are ongoing. Current knowledge pinpoints immune tolerance mechanisms as indispensable for healthy immune response to allergens in daily life. It is evident that development and maintenance of allergen-specific T cell tolerance is of vital importance for a healthy immune response to allergens. Such tolerance can be gained spontaneously by dose-dependent exposures to allergens in nature or by allergen-specific immunotherapy. Allergen-specific immunotherapy induces regulatory T cells with the capacity to secrete interleukin-10 and transforming growth factor-${\beta}$, limits activation of effector cells of allergic inflammation (such as mast cells and basophils), and switches antibody isotype from IgE to the noninflammatory type IgG4. Although allergen-specific immunotherapy is the only method of tolerance induction in allergic individuals, several factors, such as long duration of treatment, compliance problems, and life-threatening side effects, have limited widespread applicability of this immunomodulatory treatment. To overcome these limitations, current research focuses on the introduction of allergens in more efficient and safer ways. Defining the endotypes and phenotypes of allergic diseases might provide the ability to select ideal patients, and novel biomarkers might ensure new custom-tailored therapy modalities.

NF-Y binds to both G1- and G2-specific cyclin promoters; a possible role in linking CDK2/Cyclin A to CDK1/Cyclin B

  • Chae, Hee-Don;Kim, Jung-Bin;Shin, Deug-Y.
    • BMB Reports
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    • 제44권8호
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    • pp.553-557
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    • 2011
  • We previously reported that CDK2/Cyclin A can phosphorylate and activate the transcription factor NF-Y. In this study, we investigated a potential regulatory role for NF-Y in the transcription of Cyclin A and other cell cycle regulatory genes. Gel-shift assays demonstrate that NF-Y binds to CCAAT sequences in the Cyclin A promoter, as well as to those in the promoters of cell cycle G2 regulators such as CDC2, Cyclin B and CDC25C. Furthermore, expression of Cyclin A increases NF-Y's affinity for CCAAT sequences in the CDC2 promoter; however, Cyclin A's induction of CDC2 transcription is antagonized by p21, an inhibitor of CDK2/Cyclin A. These results suggest a model wherein NF-Y binds to and activates transcription from the Cyclin A promoter, increasing cellular levels of Cyclin A/CDK2 and potentiating NF-Y's capacity for transcriptional transactivation, and imply a positive feedback loop between NF-Y and Cyclin A/CDK2. Our findings are additionally indicative of a role for Cyclin A in activating Cyclin B/CDK1 through promoting NF-Y dependent transcription of Cyclin B and CDC2; NF-Y mediated crosstalk may therefore help to orchestrate cell-cycle progression.

Correlation Analysis between Regulatory Sequence Motifs and Expression Profiles by Kernel CCA

  • Rhee, Je-Keun;Joung, Je-Gun;Chang, Jeong-Ho;Zhang, Byoung-Tak
    • 한국생물정보학회:학술대회논문집
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    • 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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    • pp.63-68
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    • 2005
  • Transcription factors regulate gene expression by binding to gene upstream region. Each transcription factor has the specific binding site in promoter region. So the analysis of gene upstream sequence is necessary for understanding regulatory mechanism of genes, under a plausible idea that assumption that DNA sequence motif profiles are closely related to gene expression behaviors of the corresponding genes. Here, we present an effective approach to the analysis of the relation between gene expression profiles and gene upstream sequences on the basis of kernel canonical correlation analysis (kernel CCA). Kernel CCA is a useful method for finding relationships underlying between two different data sets. In the application to a yeast cell cycle data set, it is shown that gene upstream sequence profile is closely related to gene expression patterns in terms of canonical correlation scores. By the further analysis of the contributing values or weights of sequence motifs in the construction of a pair of sequence motif profiles and expression profiles, we show that the proposed method can identify significant DNA sequence motifs involved with some specific gene expression patterns, including some well known motifs and those putative, in the process of the yeast cell cycle.

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Targeting the Osmotic Stress Response for Strain Improvement of an Industrial Producer of Secondary Metabolites

  • Godinez, Octavio;Dyson, Paul;del Sol, Ricardo;Barrios-Gonzalez, Javier;Millan-Pacheco, Cesar;Mejia, Armando
    • Journal of Microbiology and Biotechnology
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    • 제25권11호
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    • pp.1787-1795
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    • 2015
  • The transition from primary to secondary metabolism in antibiotic-producing Streptomyces correlates with expression of genes involved in stress responses. Consequently, regulatory pathways that regulate specific stress responses are potential targets to manipulate to increase antibiotic titers. In this study, genes encoding key proteins involved in regulation of the osmotic stress response in Streptomyces avermitilis, the industrial producer of avermectins, are investigated as targets. Disruption of either osaBSa, encoding a response regulator protein, or osaCSa, encoding a multidomain regulator of the alternative sigma factor SigB, led to increased production of both oligomycin, by up to 200%, and avermectin, by up to 37%. The mutations also conditionally affected morphological development; under osmotic stress, the mutants were unable to erect an aerial mycelium. In addition, we demonstrate the delivery of DNA into a streptomycete using biolistics. The data reveal that information on stress regulatory responses can be integrated in rational strain improvement to improve yields of bioactive secondary metabolites.

Molecular Characterization of Cytoskeletal Beta-Actin and its Promoter in the Javanese Ricefish Oryzias javanicus

  • Lee, Sang Yoon;Kim, Dong Soo;Nam, Yoon Kwon
    • Fisheries and Aquatic Sciences
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    • 제15권4호
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    • pp.317-324
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    • 2012
  • We characterized the cytoskeletal beta-actin (${\beta}$-ACT) gene (actb) and its 5'-upstream regulatory region in the Javanese ricefish Oryzias javanicus. The gene and protein structures were deduced from amino acid sequences of the actb gene and conserved in the teleost lineage. The O. javanicus actb gene has common transcription factor binding motifs in its regulatory region found in teleostean orthologues. Following quantitative reverse transcription-PCR, actb gene transcripts were detected in all tissues examined; however, the basal expression levels were different. During early development, O. javanicus actb mRNA levels showed a gradual increase and peaked between late somitogenesis and the heartbeat stage. Microinjection of O. javanicus embryos with the actb gene promoter-driven red fluorescent protein (RFP) gene reporter vector showed a ubiquitous distribution of RFP signals, although most exhibited a mosaic pattern of transgene expression. A small number of microinjected embryos displayed a wide distribution of RFP signals over their entire body, which resembled the expression pattern of endogenous actb. Data from this study provide a basis to develop a transgenic system with ubiquitous expression of foreign genes in O. javanicus.

원핵세포에서 신호물질 및 조절인자로서의 3',5'-Cyclic Adenosine Monophosphate의 역할 (3',5'-Cyclic Adenosine Monophosphate (cAMP) as a Signal and a Regulatory Compound in Bacterial Cells)

  • 천세진;석영재;이규호
    • 한국미생물·생명공학회지
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    • 제34권4호
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    • pp.289-298
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    • 2006
  • 3',5'-cyclic adenosine monophosphate (cAMP) is an important molecule, which mediates diverse cellular processes. For example, it is involved in regulation of sugar uptake/catabolism, DNA replication, cell division, and motility in various acterial species. In addition, cAMP is one of the critical regulators for syntheses of virulence factors in many pathogenic bacteria. It is believed that cAMP acts as a signal for environmental changes as well as a regulatory factor for gene expressions. Therefore, intracellular concentration of cAMP is finely modulated by according to its rates of synthesis (by adenylate cyclase), excretion, and degradation (by cAMP phosphodiesterase). In the present review, we discuss the bacterial physiological characteristics governed by CAMP and the molecular mechanisms for gene regulation by cAMP. Furthermore, the effect of cAMP on phosphotransferase system is addressed.

Apelin-APJ axis inhibits TNF-alpha-mediated expression of genes involved in the inflammatory response in periodontal ligament cells

  • Lee, Gyuseok;Song, Won-Hyun;Kim, Su-Jin;Kim, Young-Gwon;Ryu, Je-Hwang
    • International Journal of Oral Biology
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    • 제44권4호
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    • pp.182-190
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    • 2019
  • Periodontitis is an inflammatory disease of the supportive tissues surrounding the teeth, and is characterized by irreversible destruction of the gingiva, periodontal ligament (PDL), and alveolar bone, which results in the loss of teeth. In the present study, we elucidated the correlation between periodontitis and apelin (APLN), an adipokine and a regulatory peptide, respectively, which are involved in inflammation and bone remodeling. The expression of APLN is negatively correlated with periodontitis progression in gingival tissue. In addition, treatment with TNF-α downregulated the expression of APLN in PDL cells and gingival fibroblasts, indicating the protective role played by APLN against periodontitis progression. The overexpression of APLN or treatment with exogenous APLN suppressed the TNF-α-mediated catabolic gene expression of MMP1, IL6, and PTGS2 in PDL cells. Moreover, the inhibition of the APLNA-PJ axis by ML221, an APJ inhibitor, induced catabolic gene expression in PDL cells. Thus, the results of this study provided evidence to support APLN as a regulatory factor of the inflammatory response during periodontitis.

Lipase Inactive Mutant of PLC-γ1 Regulates NGF-induced Neurite Outgrowth Via Enzymatic Activity and Regulation of Cell Cycle Regulatory Proteins

  • Le Xuan Nguyen, Truong;Ahn, Jee-Yin
    • BMB Reports
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    • 제40권6호
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    • pp.888-894
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    • 2007
  • Src homology (SH) domains of phospholipase C-$\gamma1$ (PLC-$\gamma1$) impair NGF-mediated PC12 cells differentiation. However, whether the enzymatic activity is also implicated in this process remains elusive. Here, we report that the enzymatic activity of phospholipase C-$\gamma1$ (PLC-$\gamma1$) is at least partially involved to the blockage of neuronal differentiation via an abrogation of MAPK activation, as well as sustained Akt activation. By contrast, Overexpression of WT-PLC-$\gamma1$ exhibited sustained NGF-induced MAPK activation, and triggered transient Akt activation resulting in profound inhibition of neurite outgrowth. However, lipase-inactive mutant (LIM) PLC-$\gamma1$ cells fail to suppress neurite outgrowth, although it contains intact SH domains, specifically enhancing the expression of cyclin D1 and p21 proteins, which regulate the function of retinoblastoma Rb protein. These observations show that the lipase inactive mutant of PLC-$\gamma1$ does not alter NGF-induced neuronal differentiation via enzymatic inability and the modulation of cell cycle regulatory proteins independent on SH3 domain.

RAS inhibitor를 이용한 항암제의 개발에 관하여

  • 어미숙
    • 미생물과산업
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    • 제19권4호
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    • pp.32-35
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    • 1993
  • ras는 활성화 형태인 GTP bound form과 비활성화 형태인 GDP bound form의 두 형태로 존재하며 두 형태를 매개하는 regulatory protein들에 의해 그 activity가 조절된다. 또한 ras는 GTP와 GDP에 강한 친화성이 있으며 세포내에는 GTP보다 GDP가 더 많이 있어서 평소에는 ras가 GDP와 결합하고 있다가 활성화될때만 GTP와 결합하는 것으로 추정된다. GDP bound ras는 guanine nucloetide exchange protein(GEP)에 의해 활성화된 GTP bound form으로 전환되며 ras의 기능이 발휘된 후에는 GTPase activating protein(GAP)에 의해 비활성화된다. Yeast의 경우 IRA1과 2의 product가 GAP의 역할을 하는 것으로 알려져 있고 CDC25 gene의 product가 GEP의 기능을 담당하는 것으로 알려져 있다. NF1 gene은 Von Recklinghausen Neurofibromatosis Type I 질병을 가진 환자에게서 발견되었는데 부분적으로 sequencing한 결과에 따르면 yeast의 IRA1/2, mammalian GAP gene product와 protein homology가 높은 것으로 나타났다. Yeast의 경우 IRA1/2 gene의 손실이나 mammalian ras gene의 transformation으로 인한 heat shock sensitivity가 NF1 gene(2,3) 혹은 GAP(4)의 expression으로 suppression된 것으로 보아 NF1이 GAP protein으로서 ras를 불활성화 시킨다는 것이 판명되었다. 결론적으로 ras의 활성은 GTP bound 혹은 GDP bound의 양쪽형태를 이동하면서 조절되는데 이 기능은 GAP과 GEP 또는 그의 유사 protein들에 의해 수행되며 이러한 regulatory protein들은 growth factor, cytokine 그리고 protein kinase 같은 signal에 의해 활성화된다고 생각된다. 본 총설에서는 ras protein의 여러가지 성질보다는 ras의 modification과 관련하여 항암제로 사용할 수 있는 ras에 specific한 약품개발의 가능성과 현재 알려진 ras의 inhibitor를 중심으로 논하고자 한다.

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Influences of different light sources and light/dark cycles on anthocyanin accumulation and plant growth in Petunia

  • Ai, Trinh Ngoc;Naing, Aung Htay;Kim, Chang Kil
    • Journal of Plant Biotechnology
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    • 제43권1호
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    • pp.119-124
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    • 2016
  • Anthocyanin accumulation and plant growth were examined in petunia (NT and $T_2$ transgenic plants) by determining the effects of different sources of light and varying light/dark cycles. Red light significantly enhanced anthocyanin content of B-peru+mPAP1; however, it had a negative effect on anthocyanin production in RsMYB1 plants. In general, white light was found to be reasonable for anthocyanin accumulation in all plants. In case of light/dark cycles, application of seven days of light:14 days of dark significantly enhanced anthocyanin content. We found that anthocyanin content detected in transgenic plants expressing anthocyanin regulatory transcription factor genes (B-peru+mPAP1 or RsMYB1) was higher than that in NT plants in all treatments. Plant growth was also influenced by the different light sources and dark/light cycles. Taken together, our results suggest that light source and light/dark cycle play an important role in anthocyanin production and plant growth. The choice of the optimal conditions is also important for anthocyanin production and plant growth depending on NT or transgenic plants carrying anthocyanin regulatory transcription factors.