scholarly journals Stability of a Spodoptera frugiperda Nucleopolyhedrovirus Deletion Recombinant during Serial Passage in Insects

2009 ◽  
Vol 76 (3) ◽  
pp. 803-809 ◽  
Author(s):  
Oihane Simón ◽  
Trevor Williams ◽  
Robert D. Possee ◽  
Miguel López-Ferber ◽  
Primitivo Caballero

ABSTRACT The stabilities of the Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) complete genome bacmid (Sfbac) and a deletion recombinant (Sf29null) in which the Sf29 gene was replaced by a kanamycin resistance cassette were determined during sequential rounds of per os infection in insect larvae. The Sf29 gene is a viral factor that determines the number of virions in occlusion bodies (OBs). The Sf29null bacmid virus was able to recover the Sf29 gene during passage. After the third passage (P3) of Sf29null bacmid OBs, the population was observed to reach an equilibrium involving a mixture of those with a kanamycin resistance cassette and those with the Sf29 gene. The biological activity of Sf29null bacmid OBs at P3 was similar to that of Sfbac OBs. The recovered gene in the Sf29null virus was 98 to 100% homologous to the Sf29 genes of different SfMNPV genotypes. Reverse transcription-PCR analysis of uninoculated S. frugiperda larvae confirmed the expression of the SfMNPV ie-0 and Sf29 genes, indicating that the insect colony harbors a covert SfMNPV infection. Additionally, the nonessential bacterial artificial chromosome vector was spontaneously deleted from both viral genomes upon passage in insects.

Open Medicine ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. 1202-1212
Author(s):  
Aichun Zhang ◽  
Yangzi Jin

AbstractAllergic rhinitis (AR) is one of the most common chronic diseases. This study examined whether microRNA (miR)-182-5p plays a role in AR by regulating toll-like receptor 4 (TLR4). First, data demonstrated that TLR4 was a target of miR-182-5p. Subsequently, AR mouse model was established to explore the role of miR-182-5p and TLR4 in AR in vivo. Initially, quantitative reverse transcription-PCR (qRT-PCR) analysis indicated that miR-182-5p was downregulated, while TLR4 expression was upregulated in AR mice. Then we found that miR-182-5p mimic reduced the frequency of sneezing and nose rubbing of the AR mice. In addition, miR-182-5p mimic significantly increased ovalbumin (OVA)-specific IgE and leukotriene C4 expression levels in nasal lavage fluid (NLF) and serum of AR mice. miR-182-5p mimic decreased the number of inflammatory cells in NLF of AR mice. It also reduced the levels of inflammatory factors in the serum of AR mice, such as interleukin (IL)-4, IL-5, IL-13, IL-17 and tumor necrosis factor (TNF)-α, while increasing the release of IFN-γ and IL-2. Finally, miR-182-5p mimic inhibited NF-κB signaling pathway activation in AR mice. However, all effects of miR-182-5p mimic on AR mice were reversed by TLR4-plasmid. In conclusion, miR-182-5p/TLR4 axis may represent a novel therapeutic target for AR.


2003 ◽  
Vol 69 (11) ◽  
pp. 6541-6549 ◽  
Author(s):  
Gilbert Thierry Lamothe ◽  
Thierry Putallaz ◽  
Han Joosten ◽  
Joey D. Marugg

ABSTRACT A seminested reverse transcription-PCR method coupled to membrane filtration was optimized to investigate the presence of norovirus (NV) RNA sequences in bottled and natural mineral waters. The recovery of viral particles by filtration varied between 28 and 45%, while the limit of detection of the overall method ranged from 6 to 95 viral particles. The assay was broadly reactive, as shown by the successful detection of 27 different viral strains representing 12 common genotypes of NVs. A total of 718 bottled and natural mineral water samples were investigated, including 640 samples of finished, spring, and line products (mostly 1 to 1.5 liters), collected from 36 different water brands of various types and from diverse geographic origins over a 2-year period. In addition, 78 samples of larger volume (10 and 400 to 500 liters) and environmental swabs were investigated. From the 1,436 analyses that were performed for the detection of NVs belonging to genogroups I and II, 34 samples (2.44%) were presumptively positive by seminested RT-PCR. However, confirmation by DNA sequence analysis revealed that all presumptive positive results were either due to nonspecific amplification or to cross-contamination. In conclusion, these results do not provide any evidence for the presence of NV genome sequences in bottled waters.


2021 ◽  
Vol 32 (4) ◽  
pp. 637-644
Author(s):  
Jamal Nasser Saleh Al-maamari ◽  
Mahardian Rahmadi ◽  
Sisca Melani Panggono ◽  
Devita Ardina Prameswari ◽  
Eka Dewi Pratiwi ◽  
...  

Abstract Objectives The study aimed to determine the effect of quercetin on the expression of primary regulator gene involved in lipogenesis and triglycerides synthesis in the liver, and the sterol regulatory binding protein-1c (SREBP-1c) mRNA in non-alcoholic fatty liver disease (NAFLD) with a high-fat diet (HFD) model. Methods Fifty-six Balb/c mice were divided into seven groups: standard feed; HFD; HFD and quercetin 50 mg/kg for 28 days; HFD and quercetin 100 mg/kg BW for 28 days; HFD and quercetin 50 mg/kg for 14 days; HFD and quercetin 100 mg/kg for 14 days; HFD and repaired fed for 14 days. Quercetin was administered intraperitoneally. The animals were sacrificed 24 h after the last treatment; the liver was taken for macroscopic, histopathological staining using hematoxylin–eosin and reverse transcription-PCR analysis sample. Results HFD significantly increased the expression of SREBP-1c mRNA; meanwhile, quercetin and repaired feed significantly reduced the expression of SREBP-1c mRNA in the liver. Quercetin at a dose of 50 mg/kg and 100 mg/kg also improved liver cells’ pathological profile in high-fat diet NAFLD. Conclusions The present study suggests that quercetin has an inhibitory effect on SREBP-1c expression and improved liver pathology in NAFLD mice.


Microbiology ◽  
2004 ◽  
Vol 150 (6) ◽  
pp. 1851-1857 ◽  
Author(s):  
Nicole Gliese ◽  
Viola Khodaverdi ◽  
Max Schobert ◽  
Helmut Görisch

The response regulator AgmR was identified to be involved in the regulation of the quinoprotein ethanol oxidation system of Pseudomonas aeruginosa ATCC 17933. Interruption of the agmR gene by insertion of a kanamycin-resistance cassette resulted in mutant NG3, unable to grow on ethanol. After complementation with the intact agmR gene, growth on ethanol was restored. Transcriptional lacZ fusions were used to identify four operons which are regulated by the AgmR protein: the exaA operon encodes the pyrroloquinoline quinone (PQQ)-dependent ethanol dehydrogenase, the exaBC operon encodes a soluble cytochrome c 550 and an aldehyde dehydrogenase, the pqqABCDE operon carries the PQQ biosynthetic genes, and operon exaDE encodes a two-component regulatory system which controls transcription of the exaA operon. Transcription of exaA was restored by transformation of NG3 with a pUCP20T derivative carrying the exaDE genes under lac-promoter control. These data indicate that the AgmR response regulator and the exaDE two-component regulatory system are organized in a hierarchical manner. Gene PA1977, which appears to form an operon with the agmR gene, was found to be non-essential for growth on ethanol.


2000 ◽  
Vol 74 (21) ◽  
pp. 10176-10186 ◽  
Author(s):  
T. Yamaguchi ◽  
S. L. Kaplan ◽  
P. Wakenell ◽  
K. A. Schat

ABSTRACT The QT35 cell line was established from a methylcholanthrene-induced tumor in Japanese quail (Coturnix coturnix japonica) (C. Moscovici, M. G. Moscovici, H. Jimenez, M. M. Lai, M. J. Hayman, and P. K. Vogt, Cell 11:95–103, 1977). Two independently maintained sublines of QT35 were found to be positive for Marek's disease virus (MDV)-like genes by Southern blotting and PCR assays. Sequence analysis of fragments of the ICP4, ICP22, ICP27, VP16, meq, pp14, pp38, open reading frame (ORF) L1, and glycoprotein B (gB) genes showed a strong homology with the corresponding fragments of MDV genes. Subsequently, a serotype 1 MDV-like herpesvirus, tentatively name QMDV, was rescued from QT35 cells in chicken kidney cell (CKC) cultures established from 6- to 9-day-old chicks inoculated at 8 days of embryonation with QT35 cells. Transmission electron microscopy failed to show herpesvirus particles in QT35 cells, but typical intranuclear herpesvirus particles were detected in CKCs. Reverse transcription-PCR analysis showed that the following QMDV transcripts were present in QT35 cells: sense and antisense meq, ORF L1, ICP4, and latency-associated transcripts, which are antisense to ICP4. A transcript of approximately 4.5 kb was detected by Northern blotting using total RNA from QT35 cells. Inoculation of QT35 cells with herpesvirus of turkeys (HVT)-infected chicken embryo fibroblasts (CEF) but not with uninfected CEF resulted in the activation of ICP22, ICP27, VP16, pp38, and gB. In addition, the level of ICP4 mRNA was increased compared to that in QT35 cells. The activation by HVT resulted in the production of pp38 protein. It was not possible to detect if the other activated genes were translated due to the lack of serotype 1-specific monoclonal antibodies.


2021 ◽  
Author(s):  
Can Chen ◽  
Yi Zong ◽  
Jiaojiao Tang ◽  
Ruisheng Ke ◽  
Lizhi Lv ◽  
...  

Background: The aim of this study was to investigate the role of miR-369-3p in hepatocellular carcinoma (HCC). Materials & methods: The expression levels of miR-369-3p were detected using the quantitative real-time reverse transcription-PCR analysis. The cell counting kit-8 and transwell assays were used to explore the effects of miR-369-3p on cell proliferation, migration and invasion of HCC cells. Results: The miR-369-3p expression was downregulated in HCC tissues and cell lines, in comparison to the normal controls, respectively. In vitro, overexpression of miR-369-3p in Hep 3B and Huh7 cells inhibited cell proliferation, migration and invasion. SOX4 was a direct target of miR-369-3p. Conclusion: Our results suggested that miR-369-3p may be a tumor suppressor in HCC by targeting SOX4.


2017 ◽  
Vol 91 (20) ◽  
Author(s):  
Kui Yang ◽  
Xiaoqun Dang ◽  
Joel D. Baines

ABSTRACT Monomeric herpesvirus DNA is cleaved from concatemers and inserted into preformed capsids through the actions of the viral terminase. The terminase of herpes simplex virus (HSV) is composed of three subunits encoded by UL15, UL28, and UL33. The UL33-encoded protein (pUL33) interacts with pUL28, but its precise role in the DNA cleavage and packaging reaction is unclear. To investigate the function of pUL33, we generated a panel of recombinant viruses with either deletions or substitutions in the most conserved regions of UL33 using a bacterial artificial chromosome system. Deletion of 11 amino acids (residues 50 to 60 or residues 110 to 120) precluded viral replication, whereas the truncation of the last 10 amino acids from the pUL33 C terminus did not affect viral replication or the interaction of pUL33 with pUL28. Mutations that replaced the lysine at codon 110 and the arginine at codon 111 with alanine codons failed to replicate, and the pUL33 mutant interacted with pUL28 less efficiently. Interestingly, genomic termini of the large (L) and small (S) components were detected readily in cells infected with these mutants, indicating that concatemeric DNA was cleaved efficiently. However, the release of monomeric genomes as assessed by pulsed-field gel electrophoresis was greatly diminished, and DNA-containing capsids were not observed. These results suggest that pUL33 is necessary for one of the two viral DNA cleavage events required to release individual genomes from concatemeric viral DNA. IMPORTANCE This paper shows a role for pUL33 in one of the two DNA cleavage events required to release monomeric genomes from concatemeric viral DNA. This is the first time that such a phenotype has been observed and is the first identification of a function of this protein relevant to DNA packaging other than its interaction with other terminase components.


2010 ◽  
Vol 84 (6) ◽  
pp. 2648-2656 ◽  
Author(s):  
Ronen Borenstein ◽  
Haim Zeigerman ◽  
Niza Frenkel

ABSTRACT Human herpesvirus 6A (HHV-6A) and HHV-6B are lymphotropic viruses which replicate in cultured activated cord blood mononuclear cells (CBMCs) and in T-cell lines. Viral genomes are composed of 143-kb unique (U) sequences flanked by ∼8- to 10-kb left and right direct repeats, DRL and DRR. We have recently cloned HHV-6A (U1102) into bacterial artificial chromosome (BAC) vectors, employing DNA replicative intermediates. Surprisingly, HHV-6A BACs and their parental DNAs were found to contain short ∼2.7-kb DRs. To test whether DR shortening occurred during passaging in CBMCs or in the SupT1 T-cell line, we compared packaged DNAs from various passages. Restriction enzymes, PCR, and sequencing analyses have shown the following. (i) Early (1992) viral preparations from CBMCs contained ∼8-kb DRs. (ii) Viruses currently propagated in SupT1 cells contained ∼2.7-kb DRs. (iii) The deletion spans positions 60 to 5545 in DRL, including genes encoded by DR1 through the first exon of DR6. The pac-2-pac-1 packaging signals, the DR7 open reading frame (ORF), and the DR6 second exon were not deleted. (iv) The DRR sequence was similarly shortened by 5.4 kb. (v) The DR1 through DR6 first exon sequences were deleted from the entire HHV-6A BACs, revealing that they were not translocated into other genome locations. (vi) When virus initially cultured in CBMCs was passaged in SupT1 cells no DR shortening occurred. (vii) Viral stocks possessing short DRs replicated efficiently, revealing the plasticity of herpesvirus genomes. We conclude that the DR deletion occurred once, producing virus with advantageous growth “conquering” the population. The DR1 gene and the first DR6 exon are not required for propagation in culture.


1999 ◽  
Vol 181 (13) ◽  
pp. 3981-3993 ◽  
Author(s):  
Sylvia A. Denome ◽  
Pamela K. Elf ◽  
Thomas A. Henderson ◽  
David E. Nelson ◽  
Kevin D. Young

ABSTRACT The penicillin binding proteins (PBPs) synthesize and remodel peptidoglycan, the structural component of the bacterial cell wall. Much is known about the biochemistry of these proteins, but little is known about their biological roles. To better understand the contributions these proteins make to the physiology ofEscherichia coli, we constructed 192 mutants from which eight PBP genes were deleted in every possible combination. The genes encoding PBPs 1a, 1b, 4, 5, 6, and 7, AmpC, and AmpH were cloned, and from each gene an internal coding sequence was removed and replaced with a kanamycin resistance cassette flanked by two ressites from plasmid RP4. Deletion of individual genes was accomplished by transferring each interrupted gene onto the chromosome of E. coli via λ phage transduction and selecting for kanamycin-resistant recombinants. Afterwards, the kanamycin resistance cassette was removed from each mutant strain by supplying ParA resolvase in trans, yielding a strain in which a long segment of the original PBP gene was deleted and replaced by an 8-bpres site. These kanamycin-sensitive mutants were used as recipients in further rounds of replacement mutagenesis, resulting in a set of strains lacking from one to seven PBPs. In addition, thedacD gene was deleted from two septuple mutants, creating strains lacking eight genes. The only deletion combinations not produced were those lacking both PBPs 1a and 1b because such a combination is lethal. Surprisingly, all other deletion mutants were viable even though, at the extreme, 8 of the 12 known PBPs had been eliminated. Furthermore, when both PBPs 2 and 3 were inactivated by the β-lactams mecillinam and aztreonam, respectively, several mutants did not lyse but continued to grow as enlarged spheres, so that one mutant synthesized osmotically resistant peptidoglycan when only 2 of 12 PBPs (PBPs 1b and 1c) remained active. These results have important implications for current models of peptidoglycan biosynthesis, for understanding the evolution of the bacterial sacculus, and for interpreting results derived by mutating unknown open reading frames in genome projects. In addition, members of the set of PBP mutants will provide excellent starting points for answering fundamental questions about other aspects of cell wall metabolism.


2020 ◽  
Author(s):  
Xiya Zuo ◽  
Shixiang Wang ◽  
Wen Xiang ◽  
Huiru Yang ◽  
Muhammad Mobeen Tahir ◽  
...  

Abstract Background: Apple (Malus domestica Borkh.) is one of the most popular cultivated fruit crops in China. Apple floral transition is an important process but liable to be affected by various environmental factors. The 14-3-3 proteins are involved in regulating diverse biological processes in plants, and some 14-3-3 members play vital roles in flowering. However, little information was available about the 14-3-3 members in apple.Results: In the current study, we identified eighteen 14-3-3 gene family members from the apple genome database, designated MdGF14a to MdGF14r. The isoforms possess a conserved core region comprising nine antiparallel α-helices and divergent N and C termini. According to their structural and phylogenetic features, Md14-3-3 proteins could be classified into two major evolutionary branches, the epsilon (ɛ) group and the non-epsilon (non-ɛ) group. Moreover, expression profiles derived from transcriptome data and quantitative real-time reverse transcription PCR analysis showed diverse expression patterns of Md14-3-3 genes in various tissues and in response to different sugars and hormone treatments during the floral transition phase. Four Md14‑3-3 isoforms (MdGF14a, MdGF14d, MdGF14i, and MdGF14j) exhibiting prominent transcriptional responses to sugars and hormones were selected for further investigation. Furthermore, yeast two-hybrid and bimolecular fluorescence complementation experiments showed that the four Md14-3-3 proteins interact with key floral integrators, MdTFL1 (TERMINAL FLOWER1) and MdFT (FLOWERING LOCUS T). Subcellular localization of four selected Md14-3-3 proteins demonstrated their localization in both the cytoplasm and nucleus.Conclusion: We identified the Md14-3-3s family in apple comprehensively. Certain Md14-3-3 genes are expressed predominantly during the apple floral transition stage, and may participate in the regulation of flowering through association with flower control genes. Our results provide a preliminary framework for further investigation into the roles of Md14-3-3s in floral transition.


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