Molecular and Biological Analysis of Potato virus M (PVM) Isolates from the Czech Republic

The sequences of the 3′‐terminal region of four Czech Potato virus M isolates VIRUBRA 4/007, VIRUBRA 4/009, VIRUBRA 4/016 and VIRUBRA 4/035 were determined and compared with sequences of PVM isolates available in GenBank. Among the Czech isolates, VIRUBRA 4/007 and 4/016 as well as VIRUBRA 4/016 and 4/035 showed the highest nucleotide identity (93%). Isolates VIRUBRA 4/007, 4/016 and 4/035 were most similar to the PV0273 isolate from Germany and to the wild isolate from Russia. Interestingly, isolate VIRUBRA 4/009 significantly differed from the other three Czech isolates and was the only European isolate that showed the highest nucleotide identity with American isolates. Moreover, the PVM isolates from the Czech Republic and Germany differed in their host range. Phylogenetic analysis based on ORF5 coding for coat protein showed that the Czech isolates could be classified in two of the three groupings of the phylogenetic tree obtained. This is the first report on molecular and biological analysis of the genome sequences of PVM isolates from the Czech Republic.     

Comparison of T Cell Receptor-Induced Proximal Signaling and Downstream Functions in Immortalized and Primary T Cells

Background

Human T cells play an important role in pathogen clearance, but their aberrant activation is also linked to numerous diseases. T cells are activated by the concurrent induction of the T cell receptor (TCR) and one or more costimulatory receptors. The characterization of signaling pathways induced by TCR and/or costimulatory receptor activation is critical, since these pathways are excellent targets for novel therapies for human disease. Although studies using human T cell lines have provided substantial insight into these signaling pathways, no comprehensive, direct comparison of these cell lines to activated peripheral blood T cells (APBTs) has been performed to validate their usefulness as a model of primary T cells.

Methodology/Principal Findings

We used quantitative biochemical techniques to compare the activation of two widely used human T cell lines, Jurkat E6.1 and HuT78 T cells, to APBTs. We found that HuT78 cells were similar to APBTs in proximal TCR-mediated signaling events. In contrast, Jurkat E6.1 cells had significantly increased site-specific phosphorylation of Pyk2, PLCγ1, Vav1, and Erk1/Erk2 and substantially more Ca²⁺ flux compared to HuT78 cells and APBTs. In part, these effects appear to be due to an overexpression of Itk in Jurkat E6.1 cells compared to HuT78 cells and APBTs. Both cell lines differ from APBTs in the expression and function of costimulatory receptors and in the range of cytokines and chemokines released upon TCR and costimulatory receptor activation.

Conclusions/Significance

Both Jurkat E6.1 and HuT78 T cells had distinct similarities and differences compared to APBTs. Both cell lines have advantages and disadvantages, which must be taken into account when choosing them as a model T cell line.     

Structure and Dynamics of a Compact State of a Multidomain Protein,the Mercuric Ion Reductase

The functional efficacy of colocalized, linked protein domains is dependent on linker flexibility and system compaction. However, the detailed characterization of these properties in aqueous solution presents an enduring challenge. Here, we employ a novel, to our knowledge, combination of complementary techniques, including small-angle neutron scattering, neutron spin-echo spectroscopy, and all-atom molecular dynamics and coarse-grained simulation, to identify and characterize in detail the structure and dynamics of a compact form of mercuric ion reductase (MerA), an enzyme central to bacterial mercury resistance. MerA possesses metallochaperone-like N-terminal domains (NmerA) tethered to its catalytic core domain by linkers. The NmerA domains are found to interact principally through electrostatic interactions with the core, leashed by the linkers so as to subdiffuse on the surface over an area close to the core C-terminal Hg(II)-binding cysteines. How this compact, dynamical arrangement may facilitate delivery of Hg(II) from NmerA to the core domain is discussed.     

Monosodium Urate Crystals Promote Innate Anti-Mycobacterial Immunity and Improve BCG Efficacy as a Vaccine against Tuberculosis

A safer and more effective anti-Tuberculosis vaccine is still an urgent need. We probed the effects of monosodium urate crystals (MSU) on innate immunity to improve the Bacille Calmette-Guerin (BCG) vaccination. Results showed that in vitro MSU cause an enduring macrophage stimulation of the anti-mycobacterial response, measured as intracellular killing, ROS production and phagolysosome maturation. The contribution of MSU to anti-mycobacterial activity was also shown in vivo. Mice vaccinated in the presence of MSU showed a lower number of BCG in lymph nodes draining the vaccine inoculation site, in comparison to mice vaccinated without MSU. Lastly, we showed that MSU improved the efficacy of BCG vaccination in mice infected with Mycobacterium tuberculosis (MTB), measured in terms of lung and spleen MTB burden. These results demonstrate that the use of MSU as adjuvant may represent a novel strategy to enhance the efficacy of BCG vaccination.     

Epigenetics Beyond Fetal Growth Restriction: A Comprehensive Overview

Molecular Diagnosis & Therapy - Fetal growth restriction is a pathological condition occurring when the fetus does not reach the genetically determined growth potential. The etiology of fetal...     

Integrative taxonomy reveals extreme morphological conservatism in sympatric Mugil species from the Tropical Southwestern Atlantic

The biodiversity crisis has had particularly harsh impacts on marine environments. However, there is still considerable uncertainty about how many species have been seriously impacted and the effectiveness of protection measures (e.g., marine protected areas or MPAs) due to high levels of cryptic species in many taxa. Here, we employ an integrative taxonomy approach to mullet species in the genus Mugil. In addition to its high economic value, this genus is notable for having diversified ~29 million years ago without marked morphological and ecological divergence. We obtained 129 specimens of Mugil from the Coral Coast MPA, the largest of its kind in the Tropical Southwestern Atlantic marine province. Although morphometric and meristic traits revealed six taxonomically recognized species, only five mitochondrial lineages were observed. All individuals morphologically identified as M. incilis belonged to the mitochondrial lineage of Mugil curema, which is consistent with misidentification of morphologically similar species and an overestimation of species diversity. Remarkably, Mugil species in our sample that diverged up to ~23 million years ago are also the most morphologically similar (M. curema and M. rubrioculus), suggesting extreme morphological conservatism, possibly driven by similarities in habitat use and life‐history traits. This study demonstrates the potential utility of integrative taxonomy (including DNA barcoding) for contributing to the conservation and sustainable use of natural resources.     

Latency type-dependent modulation of Epstein-Barr virus-encoded latent membrane protein 1 expression by type I interferons in B cells

We report that type I interferons (IFNs) upregulate latent membrane protein 1 (LMP-1) expression by direct activation of the ED-L1 promoter in several Epstein-Barr virus (EBV)-carrying Burkitt's lymphoma lines. In EBV-infected primary B cells, IFN-α transiently upregulates LMP-1 mRNA, but not protein levels, followed by downregulation of both, suggesting a novel antiproliferative mechanism of type I IFNs. Furthermore, our results may explain the expression of LMP-1 in memory B cells of systemic lupus erythematosus patients.     

Termite Feeding by <Emphasis Type="Italic">Gorilla gorilla gorilla</Emphasis> at Bai Hokou,Central African Republic

Though insectivory by large-bodied gorillas may be unexpected, researchers have reported it in all populations of gorillas studied to date. Our study of 2 well monitored groups of western gorillas (Gorilla gorilla gorilla) at Bai Hokou in Dzanga-Ndoki National Park, Central African Republic provides information on frequency and variability of termite consumption (the most commonly eaten insect) as well as some of the first direct observations of the behavior. Pooled data from both groups indicate termite feeding on 34% and 83% of days, through fecal analysis and feeding trails, respectively. Direct observations revealed that termite feeding occurred on 91% of the days for 1 group, in which the silverback fed on termites during 13% of all feeding scans, making termites the most commonly observed food item. The group that had a higher density of termite mounds in its home range consumed termites more frequently than the other group did. A higher proportion of fecal samples from the silverbacks contained termite remains than the ones from adult females and juveniles. Termite consumption was lower during the dry season, but it does not correlate with rainfall, measures of fruit availability, or fruit consumption. Displacements at termite mounds occurred more than expected, indicating that they are a patchy, sought-after food resource. Gorillas did not use tools to extract termites, but they used 2 different techniques to remove them from the cells. Though culture or social traditions may cause the variation in termite consumption across sites, further investigation of termite availability and consumption is necessary to rule out ecological and methodological explanations for observed variations.     

Expression of Recombinant Potato leafroll virus Structural and Non‐structural Proteins for Antibody Production

Vector pMPM‐A4Ω and vectors pQE‐30 and pET‐45b(+) containing the 6x His‐tag sequence were used for expression of Potato leafroll virus (PLRV) structural and non‐structural proteins in Escherichia coli. Coat protein (CP) and RNA‐dependent RNA polymerase (RdRp)–fragments RdRp_43‐616 and RdRp_304‐537 were chosen for expression. A high level of CP and RdRp_304‐537 was obtained only in an expression system using pET‐45b(+) vector and E. coli Rosetta‐gami 2(DE3) cells. After purification, the His‐tagged PLRV proteins were used for immunization of rabbits.