In this study, we completed the whole genome sequence of a new tobamovirus isolated from tomato plants grown in greenhouses in Jordan during the spring of 2015. The 6393-nt single-stranded RNA ...(ssRNA) genome encodes four proteins, as do other tobamoviruses: two replication-related proteins of 126 kDa and 183 kDa, a 30-kDa movement protein (MP) and a 17.5-kDa coat protein (CP). Phylogenetic analysis showed that this virus does not group with either the tomato mosaic virus (ToMV) or the tobacco mosaic virus (TMV) clades. Instead, it stems from a branch leading to the TMV clade. Analysis of possible recombination events between this virus and representative isolates of closely related tomato-infecting tobamoviruses showed that at least one region originated by recombination. We provide evidence that we have identified a new tobamovirus, for which we propose the name “tomato brown rugose fruit virus”.
So far there is no record of a specific virus able to infect both fungal and plant hosts in nature. However, experimental evidence shows that some plant virus RdRPs are able to perform replication in ...trans of genomic or DI RNAs in the yeast Saccharomyces cerevisiae. Furthermore, tobacco mosaic virus was recently shown to replicate in a filamentous ascomycetous fungus. Thus, at least experimentally, some plant viruses can infect some fungi. Endophytic fungi have been reported from many plants and several of these fungi have been shown to contain viruses. Here we tested if mycoviruses derived from a marine plant endophyte can replicate in plant cells. For this purpose, we used partially purified viral particles from isolate MUT4330 of Penicillium aurantiogriseum var. viridicatum which harbors six virus species, some having dsRNA and some positive-strand ssRNA genomes. These were transfected into three distinct plant protoplast cell systems. Time-course analysis of absolute RNA accumulation provided for the first time evidence that viruses of two species belonging to the Partitiviridae and Totiviridae families, can replicate in plant cells without evidence of host adaptation, i.e, changes in their nucleotide sequence.
To identify bipolar disorder (BD) genetic susceptibility factors, we conducted two genome-wide association (GWA) studies: one involving a sample of individuals of European ancestry (EA; n=1001 cases; ...n=1033 controls), and one involving a sample of individuals of African ancestry (AA; n=345 cases; n=670 controls). For the EA sample, single-nucleotide polymorphisms (SNPs) with the strongest statistical evidence for association included rs5907577 in an intergenic region at Xq27.1 (P=1.6 x 10(-6)) and rs10193871 in NAP5 at 2q21.2 (P=9.8 x 10(-6)). For the AA sample, SNPs with the strongest statistical evidence for association included rs2111504 in DPY19L3 at 19q13.11 (P=1.5 x 10(-6)) and rs2769605 in NTRK2 at 9q21.33 (P=4.5 x 10(-5)). We also investigated whether we could provide support for three regions previously associated with BD, and we showed that the ANK3 region replicates in our sample, along with some support for C15Orf53; other evidence implicates BD candidate genes such as SLITRK2. We also tested the hypothesis that BD susceptibility variants exhibit genetic background-dependent effects. SNPs with the strongest statistical evidence for genetic background effects included rs11208285 in ROR1 at 1p31.3 (P=1.4 x 10(-6)), rs4657247 in RGS5 at 1q23.3 (P=4.1 x 10(-6)), and rs7078071 in BTBD16 at 10q26.13 (P=4.5 x 10(-6)). This study is the first to conduct GWA of BD in individuals of AA and suggests that genetic variations that contribute to BD may vary as a function of ancestry.
Abstract Torradoviruses, family Secoviridae , are emergent bipartite RNA plant viruses. RNA1 is ca. 7 kb and has one open reading frame (ORF) encoding for the protease, helicase and RNA-dependent RNA ...polymerase (RdRp). RNA2 is ca. 5 kb and has two ORFs. RNA2-ORF1 encodes for a putative protein with unknown function(s). RNA2-ORF2 encodes for a putative movement protein and three capsid proteins. Little is known about the replication and polyprotein processing strategies of torradoviruses. Here, the cleavage sites in the RNA2-ORF2-encoded polyproteins of two torradoviruses, Tomato marchitez virus isolate M (ToMarV-M) and tomato chocolate spot virus, were determined by N-terminal sequencing, revealing that the amino acid (aa) at the −1 position of the cleavage sites is a glutamine. Multiple aa sequence comparison confirmed that this glutamine is conserved among other torradoviruses. Finally, site-directed mutagenesis of conserved aas in the ToMarV-M RdRp and protease prevented substantial accumulation of viral coat proteins or RNAs.
Perspectives on marine zooplankton lipids Kattner, G; Hagen, W; Lee, R F ...
Canadian journal of fisheries and aquatic sciences,
11/2007, Letnik:
64, Številka:
11
Journal Article
Recenzirano
Odprti dostop
We developed new perspectives to identify important questions and to propose approaches for future research on marine food web lipids. They were related to (i) structure and function of lipids, (ii) ...lipid changes during critical life phases, (iii) trophic marker lipids, and (iv) potential impact of climate change. The first addresses the role of lipids in membranes, storage lipids, and buoyancy with the following key question: How are the properties of membranes and deposits affected by the various types of lipids? The second deals with the importance of various types of lipids during reproduction, development, and resting phases and addresses the role of the different storage lipids during growth and dormancy. The third relates to trophic marker lipids, which are an important tool to follow lipid and energy transfer through the food web. The central question is how can fatty acids be used to identify and quantify food web relationships? With the fourth, hypotheses are presented on effects of global warming, which may result in the reduction or change in abundance of large, lipid-rich copepods in polar oceans, thereby strongly affecting higher trophic levels. The key question is how will lipid dynamics respond to changes in ocean climate at high latitudes?
During the 2007 growing season, melon (Cucumis melo) samples from the state of Guerrero in Mexico showing mosaic and other virus-like symptoms were collected for analysis. Electron microscopic ...examination of negatively stained leaf-dip extracts revealed the presence of abundant virus-like particles with features characteristic of the family Bunyaviridae. No other viral particles were observed in these preparations. However, enzyme-linked immunosorbent assays (ELISAs) specific for the most common Tospovirus spp. gave negative results. Antibodies raised against purified nucleocapsids reacted specifically with the infected leaf extracts in Western blots and double-antibody sandwich ELISA. The viral RNA was used as a template for a cDNA library, and nucleotide sequence analysis identified cloned cDNAs representing sequences corresponding to the three Tospovirus genome segments. Sequence comparisons showed that the new virus had the highest similarity to Chrysanthemum stem necrosis virus (CSNV). Phylogenetic analysis of two genome regions confirmed that this virus, provisionally named Melon severe mosaic virus (MeSMV), is a previously undescribed Tospovirus sp. belonging to the “new world” clade of Tospovirus spp. An initial survey of various cucurbit crops in various states of Mexico confirmed the widespread occurrence of this virus.
Introduction
Perfusion magnetic resonance imaging (MRI) can be used in the pre-operative assessment of brain tumours. The aim of this prospective study was to identify the perfusion parameters from ...dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast (DSC) perfusion imaging that could best discriminate between grade II and III gliomas.
Methods
MRI (3 T) including morphological ((T2 fluid attenuated inversion recovery (FLAIR) and T1-weighted (T1W)+Gd)) and perfusion (DCE and DSC) sequences was performed in 39 patients with newly diagnosed suspected low-grade glioma after written informed consent in this review board-approved study. Regions of interests (ROIs) in tumour area were delineated on FLAIR images co-registered to DCE and DSC, respectively, in 25 patients with histopathological grade II (
n
= 18) and III (
n
= 7) gliomas. Statistical analysis of differences between grade II and grade III gliomas in histogram perfusion parameters was performed, and the areas under the curves (AUC) from the ROC analyses were evaluated.
Results
In DCE, the skewness of transfer constant (
k
trans
) was found superior for differentiating grade II from grade III in all gliomas (AUC 0.76). In DSC, the standard deviation of relative cerebral blood flow (rCBF) was found superior for differentiating grade II from grade III gliomas (AUC 0.80).
Conclusions
Histogram parameters from
k
trans
(DCE) and rCBF (DSC) could most efficiently discriminate between grade II and grade III gliomas.
Most plant viruses are absolutely dependent on a vector for plant-to-plant spread. Although a number of different types of organisms are vectors for different plant viruses, phloem-feeding ...Hemipterans are the most common and transmit the great majority of plant viruses. The complex and specific interactions between Hemipteran vectors and the viruses they transmit have been studied intensely, and two general strategies, the capsid and helper strategies, are recognized. Both strategies are found for plant viruses that are transmitted by aphids in a nonpersistent manner. Evidence suggests that these strategies are found also for viruses transmitted in a semipersistent manner. Recent applications of molecular and cell biology techniques have helped to elucidate the mechanisms underlying the vector transmission of several plant viruses. This review examines the fundamental contributions and recent developments in this area.
Tomato marchitez virus (ToMarV; synonymous with Tomato apex necrosis virus) is a positive-strand RNA virus in the genus Torradovirus within the family Secoviridae. ToMarV is an emergent ...whitefly-transmitted virus that causes important diseases in tomato (Solanum lycopersicum) in Mexico. Here, the genome sequence of the ToMarV isolate M (ToMarV-M) was determined. We engineered full-length cDNA clones of the ToMarV-M genomic RNA (RNA1 and RNA2), separately, into a binary vector. Coinfiltration of both triggered systemic infections in Nicotiana benthamiana, tomato, and tomatillo (Physalis philadelphica) plants and recapitulated the biological activity of the wild-type virus. The viral progeny generated from tomato and tomatillo plants were transmissible by the whitefly Bemisia tabaci biotype B. Also, we assessed whether these infectious clones could be used for screening tomato cultivars for resistance to ToMarV and our results allowed us to differentiate resistant and susceptible tomato lines. We demonstrated that RNA1 of ToMarV-M is required for the replication of RNA2, and it can replicate independently of RNA2. From this, ToMarV-M RNA2 was used to express the green fluorescent protein in N. benthamiana plants, which allowed us to track cell-to-cell movement. The construction of full-length infectious cDNA clones of ToMarV-M provides an excellent tool to investigate virus-host-vector interactions and elucidate the functions of torradovirus-encoded proteins or the mechanisms of replication of torradovirus genomic RNA.
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