Murine model for dengue virus-induced lethal disease with increased vascular permeability

Lack of an appropriate animal model for dengue virus (DEN), which causes dengue fever and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS), has impeded characterization of the mechanisms underlying the disease pathogenesis. The cardinal feature of DHF/DSS, the severe form of DEN infection, is increased vascular permeability. To develop a murine model that is more relevant to DHF/DSS, a novel DEN strain, D2S10, was generated by alternately passaging a non-mouse-adapted DEN strain between mosquito cells and mice, thereby mimicking the natural transmission cycle of the virus between mosquitoes and humans. After infection with D2S10, mice lacking interferon receptors died early without manifesting signs of paralysis, carried infectious virus in both non-neuronal and neuronal tissues, and exhibited signs of increased vascular permeability. In contrast, mice infected with the parental DEN strain developed paralysis at late times after infection, contained detectable levels of virus only in the central nervous system, and displayed normal vascular permeability. In the mice infected with D2S10, but not the parental DEN strain, significant levels of serum tumor necrosis factor alpha (TNF-alpha) were produced, and the neutralization of TNF-alpha activity prevented early death of D2S10-infected mice. Sequence analysis comparing D2S10 to its parental strain implicated a conserved region of amino acid residues in the envelope protein as a possible source for the D2S10 phenotype. These results demonstrate that D2S10 causes a more relevant disease in mice and that TNF-alpha may be one of several key mediators of severe DEN-induced disease in mice. This report represents a significant advance in animal models for severe DEN disease, and it begins to provide mechanistic insights into DEN-induced disease in vivo.     

The process of RNA editing in plant mitochondria

RNA editing changes more than 400 cytidines to uridines in the mRNAs of mitochondria in flowering plants. In other plants such as ferns and mosses, RNA editing reactions changing C to U and U to C are observed at almost equal frequencies. Development of transfection systems with isolated mitochondria and of in vitro systems with extracts from mitochondria has considerably improved our understanding of the recognition of specific editing sites in the last few years. These assays have also yielded information about the biochemical parameters, but the enzymes involved have not yet been identified. Here we summarize our present understanding of the process of RNA editing in flowering plant mitochondria.     

New insects (Insecta: Mecoptera,Grylloblattida) from the Middle Permian Chepanikha locality,Udmurtia

New scorpionflies, Asiachorista europaea sp. nov. and Petromantis udmurtica sp. nov. (Mecoptera: Permochoristidae), and new grylloblattids, Tshepanichoptera lacera gen. et sp. nov. (Grylloblattida: Aliculidae) and Miralioma urzhumica sp. nov. (Liomopteridae), are described from the Urzhumian of Udmurtia (Chepanikha locality). Liomopterites novissimus Aristov, 2004 (Liomopteridae) is redescribed.     

瑞氏木霉表达黑曲霉葡萄糖氧化酶

利用高表达分泌纤维素酶的真菌瑞氏木霉表达重组的黑曲霉葡萄糖氧化酶。在大肠杆菌DH5α中构建瑞氏木霉纤维素酶CBHI启动子和CBHI信号肽基因黑曲霉葡萄糖氧化酶基因瑞氏木霉纤维素酶CBHI终止子构巢曲霉的甘油醛3磷酸脱氢酶启动子大肠杆菌抗潮霉素B磷酸转移酶基因构巢曲霉色氨酸C终止子pUC19(命名为pCBHGOD)质粒,线性化后用瑞氏木霉纤维素酶CBHI启动子和CBHI信号肽基因黑曲霉葡萄糖氧化酶基因瑞氏木霉纤维素酶CBHI终止子构巢曲霉的甘油醛3磷酸脱氢酶启动子大肠杆菌抗潮霉素B磷酸转移酶基因构巢曲霉色氨酸C终止子(命名为CBHGOD)核酸片段转化瑞氏木霉QM9414原生质体。用PCR扩增方法筛选出同源重组葡萄糖氧化酶基因的瑞士木霉突变株。用麦杆诱导瑞氏木霉突变株,生产黑曲霉葡萄糖氧化酶,Westernblot分析重组的葡萄糖氧化酶分子量与Sigma公司的天然黑曲霉葡萄糖氧化酶一致,生产的重组酶活性25umL,相当于Sigma公司葡萄糖氧化酶标准品的产量为0.5gL。瑞氏木霉可用于生产黑曲霉葡萄糖氧化酶。     

Taxonomy of the fossil grylloblattid nymphs (Insecta: Grylloblattida)

Nymphs of fossil grylloblattid insects are revised. Newly described taxa are Lemmatonympha gracilissima gen. et sp. nov. and Kaltanympha vorcutensis sp. nov. from the Verkhne-Syr’yaginsk locality (Ufimian, Lek-Vorkuta Formation in the Vorkuta Coal Basin), genera Sylvalitoralis gen. nov. and Tshebardanympha gen. nov. from the Tshekarda locality (Kungurian, Koshelevka Formation, Middle Urals), Tataronymphakamensis gen. et sp. nov. from the Tikhie Gory locality (Lower Kazanian, linguloid beds of the Baitugan Formation, Tatarstan), and Kaltanympha ornata sp. nov. from the Kerbo locality (Upper Tatarian, lower part of the Degali Formation, Evenki Autonomous Region). Liomopterites (?) gracilis Sharov, 1961 from Lower Kazanian deposits of the Kuznetsk Formation in the Kuznetsk Basin is transferred to the genus Kaltanympha Sharov, 1961; Permonympha arcuata Sharov, 1957 from the same locality is synonymized under Permonympha gracile Sharov, 1957; the nymph described from the Karatau locality (Upper Jurassic, Karabastau Formation in southern Kazakhstan) as Blattogryllus karatavicus Rasnitsyn, 1976 is excluded from grylloblattids. Keys to extinct grylloblattid nymphs are provided.     

New Insects (Insecta: Trichoptera,Reculida, Eoblattida) from the Mesozoic of Asia

New caddisflies, reculid and eoblattid insects from the Mesozoic of Asia are described. Caddisflies of the families Philopotamidae (Mesoviatrix paradoxa gen. et sp. nov. and Kempia piotri gen. et sp. nov.) and Polycentropodidae (Polylongevus eskovi gen. et sp. nov.) from the Upper Jurassic–Lower Cretaceous of the Kempendyai locality in Yakutia are described. A short review and comparison of fossil members in these families are provided. New Gryllones insects, Shurabia tanga sp. nov., Sauk batkenicus gen. et sp. nov. from the Sauk Tan’ga locality (Lower Jurassic of Kyrgyzstan), Say kirgizicus gen. et sp. nov. from the Shurab III locality (Reculida: Geinitziidae; Lower or Middle Jurassic of Kyrgyzstan) Griphopteron iya sp. nov. (Eoblattida: Blattogryllidae) from Iya locality (Middle Jurassic of Russia) are described.     

A new family of the order Grylloblattida (Insecta) from the Middle Permian of Russia

A new family, Ivapteridae fam. nov. (Insecta; Grylloblattida), is described from the Middle Permian locality of Soyana (Arkhangelsk Region; Kazanian Stage). It is most similar to Sojanoraphidiidae O. Martynova, 1952, differing from it in the subcostal field being traversed in the basal half of the wing by long, curved, and strongly oblique crossveins that form a double row of cells, the base of CuA being free, and CuA₁ thin compared to CuA₂. The new family is represented by a single species, Ivaptera sharovi, gen. et sp. nov. An overview of the modern system of the order Grylloblattida is included.     

New Grylloblattida (Insecta) from the Upper Permian and Lower Triassic of European Russia and Kazakhstan

New grylloblattid insects are described from the Upper Permian and Lower Triassic of European Russia and Kazakhstan: Kuplya minutissima gen. et sp. nov. (Tshekardominidae) from the Severodvinian locality Novo-Aleksandrovka (Orenburg Region); Parachauliodites orthopteroides gen. et sp. nov. (Chaulioditidae), Permofossilis commasticatus gen. et sp. nov. (Permotermopsidae), Megakhosarodes tensilis sp. nov. (Megakhosaridae), and Baharellinus dilaceratus sp. nov. (Blattogryllidae) from the Severodvinian locality Isady (Vologda Region); Dvinopedes salariovensis gen. et sp. nov. (Chaulioditidae) from the Vyatkian locality Aristovo (Vologda Region); Klyazmia karasevi gen. et sp. nov. (Chaulioditidae) from the Vyatkian locality Sokovka (Vladimir Region); Megakhosarodes borealis sp. nov. (Megakhosaridae) from the Vyatkian locality Balymotikha (Vladimir Region); Sigmophlebia rugulosa sp. nov. (Tshekardominidae) from the Upper Permian locality Karaungir (East Kazakhstan Province); and Chauliodites kitshmengensis sp. nov. and C. nedubrovensis sp. nov. (Chaulioditidae) from the Induan locality Nedubrovo (Vologda Region).     

MEF10 is required for RNA editing at nad2-842 in mitochondria of Arabidopsis thaliana and interacts with MORF8

A forwards genetic screen of a chemically mutated plant population identified mitochondrial RNA editing factor 10 (MEF10) in Arabidopsis thaliana. MEF10 is a trans-factor required specifically for the C to U editing of site nad2-842. The MEF10 protein is characterized by a stretch of pentatricopeptide repeats (PPR) and a C-terminal extension domain ending with the amino acids DYW. Editing is lost in mutant plants but is recovered by transgenic introduction of an intact MEF10 gene. The MEF10 protein interacts with multiple organellar RNA editing factor 8 (MORF8) but not with other mitochondrial MORF proteins in yeast two hybrid assays. These results support the model that specific combinations of MORF and MEF proteins are involved in RNA editing in plant mitochondria.