scholarly journals Possible Arbovirus Found in Virome of Melophagus ovinus

Viruses ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2375
Author(s):  
Alexander G. Litov ◽  
Oxana A. Belova ◽  
Ivan S. Kholodilov ◽  
Magomed N. Gadzhikurbanov ◽  
Larissa V. Gmyl ◽  
...  

Members of the Lipopteninae subfamily are blood-sucking ectoparasites of mammals. The sheep ked (Melophagus ovinus) is a widely distributed ectoparasite of sheep. It can be found in most sheep-rearing areas and can cause skin irritation, restlessness, anemia, weight loss and skin injuries. Various bacteria and some viruses have been detected in M. ovinus; however, the virome of this ked has never been studied using modern approaches. Here, we study the virome of M. ovinus collected in the Republic of Tuva, Russia. In our research, we were able to assemble full genomes for five novel viruses, related to the Rhabdoviridae (Sigmavirus), Iflaviridae, Reoviridae and Solemoviridae families. Four viruses were found in all five of the studied pools, while one virus was found in two pools. Phylogenetically, all of the novel viruses clustered together with various recently described arthropod viruses. All the discovered viruses were tested on their ability to replicate in the mammalian porcine embryo kidney (PEK) cell line. Aksy-Durug Melophagus sigmavirus RNA was detected in the PEK cell line cultural supernate after the first, second and third passages. Such data imply that this virus might be able to replicate in mammalian cells, and thus, can be considered as a possible arbovirus.

2011 ◽  
Vol 77 (9) ◽  
pp. 3023-3034 ◽  
Author(s):  
Ya-Jie Tang ◽  
Wei Zhao ◽  
Hong-Mei Li

ABSTRACTAccording to the structure of podophyllotoxin and its structure-function relationship, a novel tandem biotransformation process was developed for the directional modification of the podophyllotoxin structure to directionally synthesize a novel compound, 4-(2,3,5,6-tetramethylpyrazine-1)-4′-demethylepipodophyllotoxin (4-TMP-DMEP). In this novel tandem biotransformation process, the starting substrate of podophyllotoxin was biotransformed into 4′-demethylepipodophyllotoxin (product 1) with the demethylation of the methoxyl group at the 4′ position byGibberella fujikuroiSH-f13, which was screened out from Shennongjia prime forest humus soil (Hubei, China). 4′-Demethylepipodophyllotoxin (product 1) was then biotransformed into 4′-demethylpodophyllotoxone (product 2) with the oxidation of the hydroxyl group at the 4 position byAlternaria alternataS-f6, which was screened out from the gatheredDysosma versipellisplants in the Wuhan Botanical Garden, Chinese Academy of Sciences. Finally, 4′-demethylpodophyllotoxone (product 2) and ligustrazine were linked with a transamination reaction to synthesize the target product 4-TMP-DMEP (product 3) byAlternaria alternataS-f6. Compared with podophyllotoxin (i.e., a 50% effective concentration [EC50] of 529 μM), the EC50of 4-TMP-DMEP against the tumor cell line BGC-823 (i.e., 0.11 μM) was significantly reduced by 5,199 times. Simultaneously, the EC50of 4-TMP-DMEP against the normal human proximal tubular epithelial cell line HK-2 (i.e., 0.40 μM) was 66 times higher than that of podophyllotoxin (i.e., 0.006 μM). Furthermore, compared with podophyllotoxin (i.e., logP= 0.34), the water solubility of 4-TMP-DMEP (i.e., logP= 0.66) was significantly enhanced by 94%. For the first time, the novel compound 4-TMP-DMEP with superior antitumor activity was directionally synthesized from podophyllotoxin by the novel tandem biotransformation process developed in this work.


1988 ◽  
Vol 8 (10) ◽  
pp. 4185-4189 ◽  
Author(s):  
J A Greenspan ◽  
F M Xu ◽  
R L Davidson

The molecular mechanisms of ethyl methanesulfonate-induced reversion in mammalian cells were studied by using as a target a gpt gene that was integrated chromosomally as part of a shuttle vector. Murine cells containing mutant gpt genes with single base changes were mutagenized with ethyl methanesulfonate, and revertant colonies were isolated. Ethyl methanesulfonate failed to increase the frequency of revertants for cell lines with mutant gpt genes carrying GC----AT transitions or AT----TA transversions, whereas it increased the frequency 50-fold to greater than 800-fold for cell lines with mutant gpt genes carrying AT----GC transitions and for one cell line with a GC----CG transversion. The gpt genes of 15 independent revertants derived from the ethyl methanesulfonate-revertible cell lines were recovered and sequenced. All revertants derived from cell lines with AT----GC transitions had mutated back to the wild-type gpt sequence via GC----AT transitions at their original sites of mutation. Five of six revertants derived from the cell line carrying a gpt gene with a GC----CG transversion had mutated via GC----AT transition at the site of the original mutation or at the adjacent base in the same triplet; these changes generated non-wild-type DNA sequences that code for non-wild-type amino acids that are apparently compatible with xanthine-guanine phosphoribosyltransferase activity. The sixth revertant had mutated via CG----GC transversion back to the wild-type sequence. The results of this study define certain amino acid substitutions in the xanthine-guanine phosphoribosyltransferase polypeptide that are compatible with enzyme activity. These results also establish mutagen-induced reversion analysis as a sensitive and specific assay for mutagenesis in mammalian cells.


2013 ◽  
Vol 394 (7) ◽  
pp. 909-918 ◽  
Author(s):  
Srividya Vasu ◽  
Neville H. McClenaghan ◽  
Jane T. McCluskey ◽  
Peter R. Flatt

Abstract The novel insulin-secreting human pancreatic β-cell line, 1.1B4, demonstrates stability in culture and many of the secretory functional attributes of human pancreatic β-cells. This study investigated the cellular responses of 1.1B4 cells to lipotoxicity. Chronic 18-h exposure of 1.1B4 cells to 0.5 mm palmitate resulted in decreased cell viability and insulin content. Secretory responses to classical insulinotropic agents and cellular Ca2+ handling were also impaired. Palmitate decreased glucokinase activity and mRNA expression of genes involved in secretory function but up-regulated mRNA expression of HSPA5, EIF2A, and EIF2AK3, implicating activation of the endoplasmic reticulum stress response. Palmitate also induced DNA damage and apoptosis of 1.1B4 cells. These responses were accompanied by increased gene expression of the antioxidant enzymes SOD1, SOD2, CAT and GPX1. This study details molecular mechanisms underlying lipotoxicity in 1.1B4 cells and indicates the potential value of the novel β-cell line for future research.


2014 ◽  
Vol 3 (1) ◽  
pp. 140
Author(s):  
LUDMYLLA MENDES LIMA

<p><strong>Resumo: </strong>O presente artigo trata de analisar o modo particular como Machado de Assis constrói a representação dos fatos históricos brasileiros no romance <em>Esaú e Jacó</em>. Este romance traz em seu enredo dois importantes fatos históricos ocorridos no final do século XIX: a Abolição da Escravatura, em 1888 e a Proclamação da República, em 1889. O tratamento literário dado pelo autor aos fatos, imprimindo irrelevância aos mesmos no contexto do enredo, revela que para ser Realista ‘à brasileira’, naquelas circunstâncias específicas, era necessário mostrar o curso da História tendo como base a ausência de transformação.</p><p><strong>Palavras-chave</strong>: Machado de Assis – <em>Esaú e Jacó</em> – História do Brasil.</p><p> </p><p><strong>Abstract: </strong>This paper intends to analyze the special way Machado de Assis builds the representation of Brazilian historical facts in the novel <em>Esaú e Jacó</em>. This novel brings in its plot two important historical events that happened in the late Nineteenth century: the Abolition of Slavery, in 1888; and the Proclamation of the Republic, in 1889. The literary treatment given by the author to the events, printing irrelevance to them, in the context of the plot, reveals that to build a Brazilian realism, in those circumstances, it was necessary to show the course of history based on the absence of transformation.</p><p><strong>Keywords</strong>: Machado de Assis – <em>Esaú e Jacó –</em> Brazilian History.</p>


1996 ◽  
Vol 109 (6) ◽  
pp. 1265-1274 ◽  
Author(s):  
J. Armstrong ◽  
N. Thompson ◽  
J.H. Squire ◽  
J. Smith ◽  
B. Hayes ◽  
...  

We describe the cloning of a cDNA from the rat basophilic leukaemia cell line (RBL.2H3) encoding a novel member of the Rab family of small GTP binding proteins. The novel clone, which we call Rab8b, is most highly related to the Rab8 family with substantial divergence in the variable C-terminal domain. Northern blot analysis reveals highest levels of expression of Rab8b in the spleen, testis and brain, which is in marked contrast to the tissue distribution of Rab8. The Rab8b cDNA was modified to introduce a c-myc epitope tag at the extreme N terminus of the protein, and transient transfection studies were performed to analyse the intracellular localization of Rab8b by confocal microscopy. Transient expression of the c-myc/Rab8b fusion protein in both PC12 and RBL.2H3 cells shows staining of both the plasma membrane and ill-defined vesicular structures, and in the case of RBL.2H3 cells appears to induce striking outgrowths of the plasma membrane.


2021 ◽  
Author(s):  
Satoshi Ikegame ◽  
Mohammed Siddiquey ◽  
Chuan-Tien Hung ◽  
Griffin Haas ◽  
Luca Brambilla ◽  
...  

Abstract The novel pandemic betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected at least 120 million people since its identification as the cause of a December 2019 viral pneumonia outbreak in Wuhan, China1,2. Despite the unprecedented pace of vaccine development, with six vaccines already in use worldwide, the emergence of SARS-CoV-2 ‘variants of concern’ (VOC) across diverse geographic locales have prompted re-evaluation of strategies to achieve universal vaccination3. All three officially designated VOC carry Spike (S) polymorphisms thought to enable escape from neutralizing antibodies elicited during initial waves of the pandemic4–8. Here, we characterize the biological consequences of the ensemble of S mutations present in VOC lineages B.1.1.7 (501Y.V1) and B.1.351 (501Y.V2). Using a replication-competent EGFP-reporter vesicular stomatitis virus (VSV) system, rcVSV-CoV2-S, which encodes S from SARS coronavirus 2 in place of VSV-G, and coupled with a clonal HEK-293T ACE2 TMPRSS2 cell line optimized for highly efficient S-mediated infection, we determined that only 1 out of 12 serum samples from a cohort of recipients of the Gamaleya Sputnik V Ad26 / Ad5 vaccine showed effective neutralization (IC90) of rcVSV-CoV2-S: B.1.351 at full serum strength. The same set of sera efficiently neutralized S from B.1.1.7 and showed only moderately reduced activity against S carrying the E484K substitution alone. Taken together, our data suggest that control of some emergent SARS-CoV-2 variants may benefit from updated vaccines.


Author(s):  
Cihan Tastan ◽  
Bulut Yurtsever ◽  
Gozde Sir ◽  
Derya Dilek Kancagi ◽  
Sevda Demir ◽  
...  

AbstractThe novel coronavirus pneumonia, which was named later as Coronavirus Disease 2019 (COVID-19), is caused by the Severe Acute Respiratory Syndrome Coronavirus 2, namely SARS-CoV-2. It is a positive-strand RNA virus that is the seventh coronavirus known to infect humans. The COVID-19 outbreak presents enormous challenges for global health behind the pandemic outbreak. The first diagnosed patient in Turkey has been reported by the Republic of Turkey Ministry of Health on March 11, 2020. Today, over ninety thousand cases in Turkey, and two million cases around the world have been declared. Due to the urgent need for vaccine and anti-viral drug, isolation of the virus is crucial. Here, we report one of the first isolation and characterization studies of SARS-CoV-2 from nasopharyngeal and oropharyngeal specimens of diagnosed patients in Turkey. This study provides an isolation and replication methodology, and cell culture tropism of the virus that will be available to the research communities.Article SummaryScientists have isolated virus from Turkish COVID-19 patients. The isolation, propagation, and plaque and immune response assays of the virus described here will serve in following drug discovery and vaccine testing.


1999 ◽  
Vol 9 (2) ◽  
pp. 182-188
Author(s):  
Jessie Gu ◽  
Xin-Yuan Guan ◽  
Melissa A. Ashlock

Gene isolation methods used during positional cloning rely on physical contigs consisting of bacterial artificial chromosomes, P1, or cosmid clones. However, in most instances, the initial framework for physical mapping consists of contigs of yeast artificial chromosome (YACs), large vectors that are suboptimal substrates for gene isolation. Here we report a strategy to identify gene sequences contained within a YAC by using cDNA representational difference analysis (RDA) to directly isolate transcripts expressed from the YAC in mammalian cells. The RDA tester cDNAs were generated from a previously reported hamster cell line derived by stable transfer of a 590-kb YAC (911D5) that expressed NPC1, the human gene responsible for Niemann-Pick type C (NP-C). The driver cDNAs were generated from a control hamster cell line that did not contain the YAC that expressed NPC1. Among the gene fragments obtained by RDA,NPC1 was the most abundant product. In addition, two non-NPC1 fragments were isolated that were mapped to and expressed from 911D5. One of these RDA gene fragments (7-R) spans more than one exon and has 98% sequence identity with a human cDNA clone reported previously as an expressed sequence tag (EST), but not mapped to a chromosomal region. The other fragment (2-R) that had no significant sequence similarities with known mammalian genes or ESTs, was further localized to the region of overlap between YACs911D5 and 844E3. The latter YAC is part of a contig across the NP-C candidate region, but does not contain NPC1. This two-part approach in which stable YAC transfer is followed by cDNA RDA should be a useful adjunct strategy to expedite the cloning of human genes when a YAC contig is available across a candidate interval.[The sequence data described in this paper have been submitted to GenBank under accession nos. AF117641 and AF117642.]


1995 ◽  
Vol 108 (4) ◽  
pp. 1469-1476
Author(s):  
P.E. Hill ◽  
P.A. Walton

Peroxisomes import virtually all of their membrane and matrix proteins post-translationally. It is presently unknown whether, in mammalian cells, their exists a pool of mature peroxisomes which have received their complement of proteins and are import-incompetent. Previous work has shown that fibroblasts are capable of importing microinjected peroxisomal proteins into peroxisomes. This report describes the import of a hybrid peroxisomal protein into virtually all peroxisomes of the microinjected cell. The peroxisomal import was uniform in both short and long incubations. Pretreatment of the cells with cycloheximide did not affect the import of the peroxisomal protein, nor was there any difference in the distribution of the imported protein. Sequential microinjection experiments demonstrated that peroxisomes that had imported luciferase were capable of importing another peroxisomal protein injected 24 hours later. These results suggest that, in fibroblasts, all peroxisomes have associated protein-import machinery; this evidence does not support the hypothesis that there exists a pool of import-incompetent peroxisomes.


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