48 resultados para Traf
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Ubiquitination of proteins is a post-translational modification, which decides on the cellular fate of the protein. Addition of ubiquitin moieties to proteins is carried out by the sequential action of three enzymes: E1, ubiquitin-activating enzyme; E2, ubiquitin-conjugating enzyme; and E3, ubiquitin ligase. The TRAF-interacting protein (TRAIP, TRIP, RNF206) functions as Really Interesting New Gene (RING)-type E3 ubiquitin ligase, but its physiological substrates are not yet known. TRAIP was reported to interact with TRAF [tumor necrosis factor (TNF) receptor-associated factors] and the two tumor suppressors CYLD and Syk (spleen tyrosine kinase). Ectopically expressed TRAIP was shown to inhibit nuclear factor-kappa B (NF-κB) signalling. However, recent results suggested a role for TRAIP in biological processes other than NF-κB regulation. Knock-down of TRAIP in human epidermal keratinocytes repressed cellular proliferation and induced a block in the G1/S phase of the cell cycle without affecting NF-κB signalling. TRAIP is necessary for embryonal development as mutations affecting the Drosophila homologue of TRAIP are maternal effect-lethal mutants, and TRAIP knock-out mice die in utero because of aberrant regulation of cell proliferation and apoptosis. These findings underline the tight link between TRAIP and cell proliferation. In this review, we summarize the data on TRAIP and put them into a larger perspective regarding the role of TRAIP in the control of tissue homeostasis.
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Welsch (Projektbearbeiter): Aufruf zur Einigkeit Gesamtdeutschlands und zur Überwindung partikularstaatlicher Egoismen: "Wir woll'n in Preußen Deutsche sein." In Umformung des von Gustav Reichardt vertonten Gedichtes 'Was ist des Teutschen Vaterland?' von Ernst Moritz Arndt
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Tumor necrosis factor (TNF) receptor-associated factor (TRAF) proteins associate with and transduce signals from TNF receptor 2, CD40, and presumably other members of the TNF receptor superfamily. TRAF2 is required for CD40- and TNF-mediated activation of the transcription factor NF-kappa B. Here we describe the isolation and characterization of a novel TRAF-interacting protein, I-TRAF, that binds to the conserved TRAF-C domain of the three known TRAFs. Overexpression of I-TRAF inhibits TRAF2-mediated NF-kappa B activation signaled by CD40 and both TNF receptors. Thus, I-TRAF appears as a natural regulator of TRAF function that may act by maintaining TRAFs in a latent state.
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Federal Highway Administration, Washington, D.C.
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Federal Highway Administration, Washington, D.C.
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This paper investigates a mixed centralised-decentralised air traffic separation management system, which combines the best features of the centralised and decentralised systems whilst ensuring the reliability of the air traffic management system during degraded conditions. To overcome communication band limits, we propose a mixed separation manager on the basis of a robust decision (or min-max) problem that is posed on a reduced set of admissible flight avoidance manoeuvres (or a FAM alphabet). We also present a design method for selecting an appropriate FAM alphabet for use in the mixed separation management system. Simulation studies are presented to illustrate the benefits of our proposed FAM alphabet based mixed separation manager.
Novel TBK1 truncating mutation in a familial amyotrophic lateral sclerosis patient of Chinese origin
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Missense and frameshift mutations in TRAF family member-associated NF-kappa-B activator (TANK)-binding kinase 1 (TBK1) have been reported in European sporadic and familial amyotrophic lateral sclerosis (ALS) cohorts. To assess the role of TBK1 in ALS patient cohorts of wider ancestry, we have analyzed whole-exome sequence data from an Australian cohort of familial ALS (FALS) patients and controls. We identified a novel TBK1 deletion (c.1197delC) in a FALS patient of Chinese origin. This frameshift mutation (p.L399fs) likely results in a truncated protein that lacks functional domains required for adapter protein binding, as well as protein activation and structural integrity. No novel or reported TBK1 mutations were identified in FALS patients of European ancestry. This is the first report of a TBK1 mutation in an ALS patient of Asian origin and indicates that sequence variations in TBK1 are a rare cause of FALS in Australia. © 2015 Elsevier Inc.
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We analyze the performance of an SIR based admission control strategy in cellular CDMA systems with both voice and data traffic. Most studies In the current literature to estimate CDMA system capacity with both voice and data traf-Bc do not take signal-tlFlnterference ratio (SIR) based admission control into account In this paper, we present an analytical approach to evaluate the outage probability for voice trafllc, the average system throughput and the mean delay for data traffic for a volce/data CDMA system which employs an SIR based admission controL We show that for a dataaniy system, an improvement of about 25% In both the Erlang capacity as well as the mean delay performance is achieved with an SIR based admission control as compared to code availability based admission control. For a mixed voice/data srtem with 10 Erlangs of voice traffic, the Lmprovement in the mean delay performance for data Is about 40%.Ah, for a mean delay of 50 ms with 10 Erlangs voice traffic, the data Erlang capacity improves by about 9%.
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TNF receptor associated factor 1 (TRAF1) plays an important role in regulating the TNF signaling and protecting cells from apoptosis. In the present study, a TRAF1 gene has been cloned from grass carp (Ctenopharyngodon idella) by reverse transcription (RT)-PCR and rapid amplification of cDNA ends (RACE). The full-length cDNA is 2235 bp, including a 250 bp 5' UTR (untranslated region), a 1659 bp open reading frame, and a 326 bp 3'UTR. The polyadenylation signal (AATAAA, AATAA) and one mRNA instability motif (AUUUA) were found followed by a poly (A) tail in the 3'UTR. No signal peptide or transmembrane region has been found in the putative amino acids of grass carp TRAF1 (gcTRAF1). The putative amino acids of gcTRAF1 share 72% identity with the homologue in zebrafish. It is characterized by a zinc finger at the N-terminus and a TRAF domain (contains one TRAF-C and one TRAF-N) at the C-terminus. The identity of the TRAF domain among all the TRAF1 homologues in vertebrates varies from 52% to 58%, while the identities of TRAF-C were almost the same as 70%. The recombinant gcTRAF1 has been constructed successfully and expressed in Escherichia coli by using pET-32a expression vector. The polyclonal antibody for rabbit has been successfully obtained. The expression of gcTRAF1 in different organs was examined by real-time quantitative PCR and Western blotting, respectively. It was widely distributed in heart, head kidney, thymus, brain, gill, liver, spleen, and trunk kidney. This is the first report of TRAF1 homologue molecule found in fish. (c) 2007 Elsevier B.V. All rights reserved.
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Tumor necrosis factor receptor-associated factor 2 (TRAF2) is a crucial component of almost the entire tumor necrosis factor receptor superfamily signaling pathway. In the present study, a TRAF2 gene has been cloned from grass carp (Ctenopharyngodon idella) by reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends. The full-length cDNA is 3162 bp, including a 60 bp 5' untranslated region (UTR), a 1611 bp open reading frame, and a 1491 bp 3' UTR. The polyadenylation signal (AATAAA) and the mRNA instability motifs (ATTTTA, ATTTA) were followed by a poly(A) tail in the 3' UTR. No signal peptide or transmembrane region has been found in the putative amino acids of grass carp TRAF2 (gcTRAF2). Phylogenetic tree analysis clearly showed that gcTRAF2 is nearest to the TRAF2 gene of goldfish. The identity of gcTRAF2 with its homologs in other vertebrates ranges from 56% to 97%. It is characterized by one RING-type signature at the N-terminus, one zinc finger in the middle part, and one conserved TRAF domain consisting of a C-proximal (TRAF-C) subdomain and a N-proximal (TRAF-N) subdomain. The identity of TRAF-C among all TRAF2 homologs in vertebrates varies from 78% to 97%, whereas the identity of TRAF-N ranges from 56% to 100%. The recombinant gcTRAF2 has been expressed in Escherichia coli using pET-32a expression vector. The rabbit anti-gcTRAF2 polyclonal antibody was obtained. The expression of gcTRAF2 in different organs was examined by real-time quantitative polymerase chain reaction and Western blot analysis. It was widely distributed in heart, head kidney, thymus, brain, gill, liver, spleen, and trunk kidney. This is the first report of a TRAF2 homolog molecule in fish.
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Tumor necrosis factor receptor-associated factor 6 (TRAF6), a key signaling adaptor molecule common to the TNFR superfamily and IL-IR/TLR family, is important not only for a diverse array of physiological processes functions of the TNFR superfamily, but also is involved in adaptive immunity and innate immunity. In this report, the first bivalve TRAF6 (named as CfTRAF6) gene is identified and characterized from Zhikong scallop Chlamys farreri. The full-length cDNA of CfTRAF6 is of 2510 bp, consisting of a 5'-terminal untranslated region (UTR) of 337 bp, a 3'-terminal UTR of 208 bp with a canonical polyadenylation signal sequence AATAAA and a poly (A) tail, and an open reading frame (ORF) encoding a polypeptide of 655 amino acids. The predicted amino acid sequence of CfTRAF6 comprises characteristic motifs of the TRAF proteins, including a Zinc finger of RING-type, two Zinc fingers of TRAF-type, a coiled-coil region, and a MATH (the meprin and TRAF homology) domain. The overall amino acid sequence identity between CfTRAF6 and other TRAF6s is 28-68%. Phylogenetic analyses of CfTRAF6 sequence with TRAF sequences from other organisms indicate that CfTRAF6 is a true TRAF6 orthologue. The mRNA expression of CfTRAF6 in various tissues is measured by Real-time RT-PCR. The mRNA transcripts are constitutively expressed in tissues of haemocyte, muscle, mantle, heart, gonad and gill, but the highest expression is observed in the gonad. The temporal expressions of CfTRAF6 mRNA in the mixed primary cultured haemocytes are recorded after treatment with 20 mu g mL(-1) and 0.5 mu g mL(-1) peptido-glycan (PGN). The expression level of CfTRAF mRNA is down-regulated from 1.5 h to 3 h after the treatment with 0.5 mu g mL(-1) PGN, and then recovers to the original level. While the expression of CfTRAF6 is obviously decreased after treatment with 20 mu g mL(-1) PGN, and reach the lowest point (only about 1/9 times to control) at 3 h. The result Suggests that CfTRAF6 can be greatly regulated by PGN and it may be involved in signal transduction and immune response of scallop. (C) 2008 Published by Elsevier Ltd.
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扇贝是我国海水养殖的重要品种,但自1994年以来,养殖扇贝陆续爆发的大规模死亡,不但造成了巨大的经济损失,而且直接威胁到现有产业的生存和发展。引起扇贝大规模死亡原因是多方面的,其主要原因是养殖环境恶化、扇贝种质衰退和抗病力下降。因此,深入研究扇贝免疫防御机制,探讨提高机体抗病力的有效途径和方法,改良种质和培育抗病品系,无疑是解决目前困扰扇贝养殖业健康可持续发展的必经之路。 Toll样受体(TLRs)家族是新近发现的模式识别受体(PRRs),参与识别病原体相关的分子模式(PAMPs),在天然免疫系统中起着非常重要的作用。哺乳动物中Toll样受体信号通路还参与诱导树枝状细胞成熟、参与免疫耐受、参与凋亡发生发展、介导非感染性因素的识别等,被视为联系天然免疫和获得性免疫的桥梁。同时果蝇的Toll信号通路也是不具备获得性免疫的果蝇赖以抵御病毒、细菌和真菌感染,介导天然免疫反应的重要信号通路。 本研究采用大规模EST测序方法,结合Genome Walker库的构建和cDNA末端快速扩增技术,从栉孔扇贝克隆得到CfToll-1、CfMyd88、CfTRAF6和CfCactus这四个Toll样受体信号通路基因的全长cDNA,同时用荧光实时定量PCR技术检测了这些基因的组织分布及在脂多糖(LPS)和肽聚糖(PGN)刺激下的表达规律。 栉孔扇贝Toll样受体(CfToll-1)的cDNA序列全长4308 bp,包含5’非翻译区(UTR)211 bp,3597 bp的开放阅读框,500 bp的3’UTR,最后为18个腺嘌呤的ploy A 尾巴。开放阅读框编码1198个氨基酸的多肽,该多肽的估计分子量为137.41kd,估计的等电点为5.62,该多肽有信号肽,具有一个预测的跨膜区,因此是一种跨膜蛋白。经BLAST比对,CfToll-1基因与节肢动物多种Toll蛋白高度的相似性。SMART(Simple Modular Architecture Research Tool)软件分析,CfToll-1包含典型的Toll样受体的结构:富含亮氨酸的重复序列的胞外区(leucine-rich repeats, LRR),一段跨膜结构域,以及胞内区的TIR结构域(Toll/IL-1 receptor homologous region)。利用Real-time RT-PCR发现CfToll-1mRNA在扇贝体内普遍存在于血细胞、肌肉、外套膜、心、性腺和鳃组织中。利用体外培养的原代血细胞系研究不同浓度LPS刺激后CfToll-1的表达变化,结果显示低剂量(100ng.mL-1 )LPS 使CfToll-1 mRNA表达量减小,该变化在1.5h、3h 和9h组差异显著,虽然在6h组表达量稍有恢复,但尚未达到对照水平;用1μg.mL-1LPS处理细胞时, 6h组CfToll-1表达量明显上调,约为对照水平的2倍。证实细菌结构脂多糖对CfToll-1基因的表达有影响,且这种影响有剂量依赖效应。 栉孔扇贝Myd88同源基因(CfMyd88)的cDNA序列全长1554bp,包含5’UTR 427 bp,1101bp的开放阅读框,最后为18个腺嘌呤的ploy A 尾。CfMyd88的开放阅读框可编码367个氨基酸的多肽,该多肽的估计分子量为42.37kD,估计的等电点为5.71。利用SMART程序分析发现CfMyd88编码了Death和TIR结构域, 这两个结构域是Myd88特征结构。BLAST程序发现扇贝的序列与数据库哺乳动物的Myd88基因高度同源。原代培养的扇贝血细胞在受到PGN刺激后,CfMyd88 mRNA表达在1.5小时开始下调,直到9小时下调至对照表达量的1/10,证实肽聚糖结构对CfMyd88基因的表达有影响。 栉孔扇贝TRAF6同源基因(CfTRAF6)的cDNA序列全长2510bp,包含5’UTR 337 bp,1965bp的开放阅读框,3’UTR 208bp,最后为21 个腺嘌呤的ploy A 尾巴。CfTRAF6开放阅读框编码655个氨基酸的多肽,该多肽的估计分子量为74.09kD,估计的等电点为6.01。InterPro Scan在线分析发现CfTRAF6有典型的TRAF蛋白家族的特征结构,包括的一个指环结构,两个锌指结构,一个MATH (the meprin and TRAF homology)结构域以及Coiled-coil区域。CfTRAF6的序列与数据库多物种的TRAF6高度同源,同源性最高的是乌贼序列(Identity=68)和鼠类(Identity=45%)。利用Real-time RT-PCR,发现CfTRAF6在各组织普遍存在,在性腺中的表达最高。原代培养的扇贝血细胞在受到不同浓度PGN刺激后,与CfMyd88的情况一样,CfTRAF6的表达量变化减少,且这种变化随剂量的增加更加明显。 栉孔扇贝Cactus同源基因(CfCactus)的cDNA序列全长2488bp,包含5’UTR 181 bp,840bp的开放阅读框, 3’UTR 1467bp,最后为19个腺嘌呤的ploy A 尾巴。CfCactus的开放阅读框编码279个氨基酸的多肽,该多肽的估计分子量为31.37 kD;估计的等电点为4.74,与果蝇的Cactus基因的等电点相近(4.5)。利用SMART程序分析发现CfCactus主要编码了ANK结构域(ankyrin repeats)。Cactus基因为哺乳动物NF-κB抑制蛋白IκB的同源分子,BLAST 程序发现扇贝的序列与数据库多物种的Cactus或IκB基因高度同源。同源性最高的是太平洋牡蛎(Identity=35%)和圆尾鲎(Identities = 44%)。对CfTCactus mRNA在扇贝的血细胞、性腺、 肠的组织表达进行分析,并同时与CfTRAF6和CfMyd88的表达量进行了对比,发现CfCactus的表达水平明显高于这两个基因,而且CfTRAF6的基因表达量也高于CfMyd88,表现出级联放大效应。正常情况下,三个基因在性腺的表达量最高,推测这条通路可能和发育等功能密切相关。 通过本研究我们首次在双壳类软体动物找得到与果蝇Toll蛋白家族高度同源的CfToll-1基因,同时发现其他三个在Toll样受体信号传递过程中起重要作用的基因,其中包括在软体动物中获得的第一个Toll样受体的接头分子-CfMyd88基因,该结果直接证明软体动物具有与哺乳动物和节肢动物高度类似Myd88依赖的Toll样受体信号通路。同时通过这些基因组织分布的研究以及细菌结构LPS和PGN对这条通路上基因表达的影响,证明扇贝Toll信号通路可能与在果蝇中一样,参与扇贝的发育和免疫防御等多种功能。
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Web threats are becoming a major issue for both governments and companies. Generally, web threats increased as much as 600% during last year (WebSense, 2013). This appears to be a significant issue, since many major businesses seem to provide these services. Denial of Service (DoS) attacks are one of the most significant web threats and generally their aim is to waste the resources of the target machine (Mirkovic & Reiher, 2004). Dis-tributed Denial of Service (DDoS) attacks are typically executed from many sources and can result in large traf-fic flows. During last year 11% of DDoS attacks were over 60 Gbps (Prolexic, 2013a). The DDoS attacks are usually performed from the large botnets, which are networks of remotely controlled computers. There is an increasing effort by governments and companies to shut down the botnets (Dittrich, 2012), which has lead the attackers to look for alternative DDoS attack methods. One of the techniques to which attackers are returning to is DDoS amplification attacks. Amplification attacks use intermediate devices called amplifiers in order to amplify the attacker's traffic. This work outlines an evaluation tool and evaluates an amplification attack based on the Trivial File Transfer Proto-col (TFTP). This attack could have amplification factor of approximately 60, which rates highly alongside other researched amplification attacks. This could be a substantial issue globally, due to the fact this protocol is used in approximately 599,600 publicly open TFTP servers. Mitigation methods to this threat have also been consid-ered and a variety of countermeasures are proposed. Effects of this attack on both amplifier and target were analysed based on the proposed metrics. While it has been reported that the breaching of TFTP would be possible (Schultz, 2013), this paper provides a complete methodology for the setup of the attack, and its verification.