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91.
The complete nucleotide sequences of the mitochondrial genome (mitogenome) of the oriental mole cricket, Gryllotalpa orientalis (Orthoptera: Gryllotalpidae), were determined. The 15,521-bp-long G. orientalis mitogenome contains typical gene complement, base composition, and codon usage found in metazoan mitogenomes. The G. orientalis mitogenome contains the third lowest A+T content (70.5%) among the complete insects mt genome sequences. The initiation codon for the G. orientalis COI gene appears to be ATG, instead of the tetranucleotides, which have been postulated to act as initiation codon for Locusta migratoria and some lepidopteran COI genes. The initiation codon for ND2 appears to be GTG, which is rare, but has been designated as an initiator of Tricholepidion gertschi ND2. All anticodons of G. orientalis tRNAs were identical to Drosophila yakuba and L. migratoria. The tRNA(Ser)(AGN) could not form a stable stem loop structure in the DHU arm as shown in many other insect tRNA(Ser)(AGN). Phylogenetic analysis of nucleotide sequence information from all mt genes supported a monophyletic Diptera, a monophyletic Lepidoptera, a monophyletic Coleoptera, a monophyletic Mecopterida (Diptera+Lepidoptera), and a monophyletic Endopterygota (Diptera+Lepidoptera+Coleoptera), suggesting that the complete insect mitogenome sequence has a resolving power to the diversification events within Endopterygota. However, the relationships of ancient insect orders were unstable, indicating the limited use of mitogenome information at deeper phylogenetic depth. 相似文献
92.
Malherbe DC Erpenbeck VJ Abraham SN Crouch EC Hohlfeld JM Wright JR 《American journal of physiology. Lung cellular and molecular physiology》2005,289(5):L856-L866
Mast cells play a key role in allergy and asthma. They reside at the host-environment interface and are among the first cells to make contact with inhaled microorganisms and particulate antigens. Pulmonary surfactant proteins A and D (SP-A and SP-D) function in lung host defense by enhancing microbe phagocytosis and mediating other immune cell functions, but little is known about their effects on mast cells. We hypothesized that SP-A and/or SP-D modulate IgE-dependent mast cell functions. Pollen starch granules (PSG) extracted from Dactylis glomerata and coated with trinitrophenol (TNP) were used as a model of an inhaled organic particulate allergen. Our data revealed that SP-D inhibited by 50% the release of beta-hexosaminidase by peritoneal mast cells sensitized with IgE anti-TNP and stimulated with TNP-PSG. In contrast, SP-A had no effect. Furthermore, SP-D aggregated PSG in a dose-dependent manner, and this aggregation was mediated by SP-D's carbohydrate recognition domain. A single arm SP-D mutant (RrSP-Dser15,20) neither aggregated PSG nor inhibited degranulation, suggesting that multimerization of SP-D is required for maximal PSG aggregation and inhibition of PSG-induced mast cell degranulation. This study is the first to demonstrate that SP-D modulates IgE-mediated mast cell functions, which are important in asthma and allergic inflammation. 相似文献
93.
Thermostable Pseudomonas fluorescens SIK W1 lipase (PFL), which is responsible for the spoilage of milk, was overexpressed as inclusion bodies in Escherichia coli. Renaturation of solubilized PFL was achieved by using size-exclusion protein refolding chromatography. The renatured enzyme was purified homogeneously using a combination of gel filtration and ion-exchange FPLC. Its specific activity was found to be enhanced in the presence of Ca2+. Secondary structural changes induced by Ca2+ were monitored by circular dichroism, which demonstrated that the activity increase of PFL in the presence of Ca2+ is strongly correlated with significant increases in alpha-helix and beta-sheet content. In the presence of Ca2+, the PFL structure was found resistant to denaturation by guanidine hydrochloride and to enzyme activity loss due to cosolvents like DMSO and trifluoroethanol, suggesting that Ca2+ plays an important role in inducing conformational changes and consequently in maintaining enzyme structural stability. 相似文献
94.
Genomic segments cloning and analysis of Cotesia plutellae polydnavirus using plasmid capture system
Choi JY Roh JY Kang JN Shim HJ Woo SD Jin BR Li MS Je YH 《Biochemical and biophysical research communications》2005,332(2):487-493
Cotesia plutellae polydnaviruses (CpBV) has a segmented genome consisting of multiple circular double stranded DNAs. Recently, we have developed an easy, simple, and convenient system based on Tn7 transposition in order to clone genomic segments of CpBV in Escherichia coli cell and designated plasmid capture system (PCS). The PCS donor-S transferred a pUC19 origin of replication and an ampicillin resistance marker into CpBV genomic DNA by in vitro transposition. Through PCS system, we were able to clone 53 genomic clones ranging from 0.1 to 25.5 kb and further they were classified into 29 segments by their sizes and restriction endonuclease patterns. Among them, a complete nucleotide sequence of CpBV-S28 segment was determined and 10 putative genes were predicted from this segment. Interestingly, 9 of 10 putative ORFs had high level of similarities with catalytic domain of protein tyrosine phosphatase. Also, ORF2807 showed similarity with EP1-like proteins of C. congregata polydnavirus. 相似文献
95.
The alveolar epithelium is lined by surfactant, a lipoprotein complex that both reduces surface tension and mediates several innate immune functions including bacterial aggregation, alteration of alveolar macrophage function, and regulation of bacterial clearance. Surfactant protein-D (SP-D) participates in several of these immune functions, and specifically it enhances the clearance of the pulmonary pathogen Pseudomonas aeruginosa, a common cause of morbidity and mortality in cystic fibrosis (CF) patients. P. aeruginosa secretes a variety of virulence factors including elastase, a zinc-metalloprotease, which degrades both SP-A and SP-D. Here we show that SP-D is cleaved by elastase to produce a stable 35-kDa fragment in a time-, temperature-, and dose-dependent manner. Degradation is inhibited by divalent metal cations, a metal chelator, and the elastase inhibitor, phosphoramidon. Sequencing the SP-D degradation products localized the major cleavage sites to the C-terminal lectin domain. The SP-D fragment fails to bind or aggregate bacteria that are aggregated by intact SP-D. SP-D fragment is observed when normal rat bronchoalveolar lavage (BAL) is treated with Pseudomonas aeruginosa elastase, and SP-D fragments are present in the BAL of CF lung allograft patients. These data show that degradation of SP-D occurs in the BAL environment and that degradation eliminates many normal immune functions of SP-D. 相似文献
96.
Akeson EC Donahue LR Beamer WG Shultz KL Ackert-Bicknell C Rosen CJ Corrigan J Davisson MT 《Genomics》2006,87(2):311-313
Mice of the inbred mouse strain C3H/HeJ have been shown to be homozygous for a chromosomal inversion on Chromosome (Chr) 6. The inversion encompasses about 20% of the chromosome from approximately 73 Mb to approximately 116 Mb. The importance of this finding is that linkage crosses using C3H/HeJ will show no recombination in this region of Chr 6. The inversion has no apparent effect on the phenotype of C3H/HeJ mice and its presence should not affect biological studies; however, use of C3H/HeJ mice for genetic analysis of Chr 6 should be avoided or the results interpreted with the inversion in mind. The inversion has been named In(6)1J (inversion Chr 6, Jackson 1). 相似文献
97.
Stadthagen G Jackson M Charles P Boudou F Barilone N Huerre M Constant P Liav A Bottova I Nigou J Brando T Puzo G Daffé M Benjamin P Coade S Buxton RS Tascon RE Rae A Robertson BD Lowrie DB Young DB Gicquel B Griffin R 《Microbes and infection / Institut Pasteur》2006,8(8):2245-2253
p-Hydroxybenzoic acid derivatives (p-HBADs) are glycoconjugates secreted by all Mycobacterium tuberculosis isolates whose contribution to pathogenicity remains to be determined. The pathogenicity of three transposon mutants of M. tuberculosis deficient in the biosynthesis of some or all forms of p-HBADs was studied. Whilst the mutants grew similarly to the wild-type strain in macrophages and C57BL/6 mice, two of the mutants induced a more severe and diffuse inflammation in the lungs. The lack of production of some or all forms of p-HBADs in these two mutants also correlated with an increased secretion of the pro-inflammatory cytokines tumour-necrosis factor alpha, interleukin 6 and interleukin 12 in vivo. We propose that the loss of production of p-HBADs by tubercle bacilli results in their diminished ability to suppress the pro-inflammatory response to infection and that this ultimately provokes extensive pulmonary lesions in the C57BL/6 model of tuberculosis infection. 相似文献
98.
Gowdy KM Cardona DM Nugent JL Giamberardino C Thomas JM Mukherjee S Martinu T Foster WM Plevy SE Pastva AM Wright JR Palmer SM 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(10):4897-4905
Graft-versus-host disease (GVHD) is a severe and frequent complication of allogeneic bone marrow transplantation (BMT) that involves the gastrointestinal (GI) tract and lungs. The pathobiology of GVHD is complex and involves immune cell recognition of host Ags as foreign. We hypothesize a central role for the collectin surfactant protein A (SP-A) in regulating the development of GVHD after allogeneic BMT. C57BL/6 (H2b; WT) and SP-A-deficient mice on a C57BL/6 background (H2b; SP-A(-/-)) mice underwent allogeneic or syngeneic BMT with cells from either C3HeB/FeJ (H2k; SP-A-deficient recipient mice that have undergone an allogeneic BMT [SP-A(-/-)alloBMT] or SP-A-sufficient recipient mice that have undergone an allogeneic BMT) or C57BL/6 (H2b; SP-A-deficient recipient mice that have undergone a syngeneic BMT or SP-A-sufficient recipient mice that have undergone a syngeneic BMT) mice. Five weeks post-BMT, mice were necropsied, and lung and GI tissue were analyzed. SP-A(-/-) alloBMT or SP-A-sufficient recipient mice that have undergone an allogeneic BMT had no significant differences in lung pathology; however, SP-A(-/-)alloBMT mice developed marked features of GI GVHD, including decreased body weight, increased tissue inflammation, and lymphocytic infiltration. SP-A(-/-)alloBMT mice also had increased colon expression of IL-1β, IL-6, TNF-α, and IFN-γ and as well as increased Th17 cells and diminished regulatory T cells. Our results demonstrate the first evidence, to our knowledge, of a critical role for SP-A in modulating GI GVHD. In these studies, we demonstrate that mice deficient in SP-A that have undergone an allogeneic BMT have a greater incidence of GI GVHD that is associated with increased Th17 cells and decreased regulatory T cells. The results of these studies demonstrate that SP-A protects against the development of GI GVHD and establishes a role for SP-A in regulating the immune response in the GI tract. 相似文献
99.
Denton PW Olesen R Choudhary SK Archin NM Wahl A Swanson MD Chateau M Nochi T Krisko JF Spagnuolo RA Margolis DM Garcia JV 《Journal of virology》2012,86(1):630-634
Here we demonstrate that a combination of tenofovir, emtricitabine, and raltegravir effectively suppresses peripheral and systemic HIV replication in humanized BLT mice. We also demonstrate that antiretroviral therapy (ART)-treated humanized BLT mice harbor latently infected resting human CD4+ T cells that can be induced ex vivo to produce HIV. We observed that the levels of infected resting human CD4+ T cells present in BLT mice are within the range of those observed circulating in patients undergoing suppressive ART. These results demonstrate the potential of humanized BLT mice as an attractive model for testing the in vivo efficacy of novel HIV eradication strategies. 相似文献
100.
Urdaz-Rodríguez J Fosgate G Alleman AR Rae O Donovan A Binford M Zaragoza A Melendez P 《Experimental & applied acarology》2012,58(2):145-157
A prevalence study was conducted to survey tick larvae populations in Puerto Rico (PR), compare the number of infested sites with Rhipicephalus (Boophilus) microplus larvae between the wet and dry season, and assess the associations of ecologic factors on the presence of R. microplus larvae. Ninety-six sites were selected using a GIS-based sampling method. Each site was sampled twice; the first sampling was performed during the dry season (March 4-18, 2007) and the second sampling during the wet season (August 13-26, 2007). Sites were sampled using a tick drag with a 1-m(2) white flannel cloth along a 50-m straight course. Only 2 tick species were identified. In the dry season, 15 sites (0.16, 95?% CI?=?0.09-0.24) were identified with R. microplus larvae (n?=?606) and 9 sites (0.09, 95?% CI?=?0.04-0.17) with Dermacentor (Anocentor) nitens larvae (n?=?779), whereas in the wet season 5 sites (0.05, 95?% CI?=?0.02-0.12) were identified with R. microplus (n?=?94), and 5 sites (0.05?%, 95?% CI = 0.02-0.12) with D. nitens (n?=?275). Difference in the number of infested sites with R. microplus was significant (P =?0.031) between the 2 seasons. Factors associated with the presence of R. microplus larvae in PR were wind speed of >4.0?km/h (OR?=?0.07, 95?% CI?=?0.01-0.63), more than 25?% bushes and shrubs on the site (OR?=?11, 95?% CI?=?1.6-71), and presence of cattle on the site (OR?=?26, 95?% CI?=?3.4-188). 相似文献