Revisiting the use of Iprodione and Trichoderma in the integrated management of onion white rot

The biocontrol properties of Trichoderma species are well documented, but their effectiveness in antagonism of the problematic Sclerotium cepivorum, the causal agent of white rot in Allium species, appears limited with reports of significant control only relating to deliberately-mutated strains of Trichoderma. Our previous studies have indicated the possibility of using selected naturally-occurring strains of the antagonist in the suppression of other diseases; now in vitro and controlled environment in vivo studies have indicated that a degree of control of Onion White Rot is possible, and that the selected antagonist strains can be used in integrated treatments with Iprodione to good effect. The possible value of such treatments is considered in light of other approaches to the suppression of this continuing problem.     

Inhibition of diverse opportunistic viruses by structurally optimized retrograde trafficking inhibitors

Opportunistic viruses are a major problem for immunosuppressed individuals, particularly following organ or stem cell transplantation. Current treatments are non-existent or suffer from problems such as high toxicity or development of resistant strains. We previously published that a trafficking inhibitor that targets a host protein greatly reduces the replication of human cytomegalovirus. This inhibitor was also shown to be moderately effective against polyomaviruses, another family of opportunistic viruses. We have developed a panel of analogues for this inhibitor and have shown that these analogues maintain their high efficacy against HCMV, while substantially lowering the concentration required to inhibit polyomavirus replication. By targeting a host protein these compounds are able to inhibit the replication of two very different viruses. These observations open up the possibility of pan-viral inhibitors for immunosuppressed individuals that are effective against multiple, diverse opportunistic viruses.     

A web server to locate periodicities in a sequence

Summary : FT is a tool written in C++, which implements the Fourier analysis method to locate periodicities in aminoacid or DNA sequences. It is provided for free public use on a WWW server with a Java interface. Availability : The server address is http://o2.db. uoa.gr/FT Contact : shamodr@atlas.uoa.gr      

Utility of the white gene in estimating phylogenetic relationships among mosquitoes (Diptera: Culicidae)

The utility of a nuclear protein-coding gene for reconstructing phylogenetic relationships within the family Culicidae was explored. Relationships among 13 species representing three subfamilies and nine genera of Culicidae were analyzed using a 762-bp fragment of coding sequence from the eye color gene, white. Outgroups for the study were two species from the sister group Chaoboridae. Sequences were determined from clone PCR products amplified from genomic DNA, and aligned following conceptual intron splicing and amino acid translation. Third codon positions were characterized by high levels of divergence and biased nucleotide composition, the intensity and direction of which varied among taxa. Equal weighting of all characters resulted in parsimony and neighboring-joining trees at odds with the generally accepted phylogenetic hypothesis based on morphology and rDNA sequences. The application of differential weighting schemes recovered the traditional hypothesis, in which the subfamily Anophelinae formed the basal clade. The subfamily Toxorhynchitinae occupied an intermediate position, and was a sister group to the subfamily Culicinae. Within Culicinae, the genera Sabethes and Tripteroides formed an ancestral clade, while the Culex-Deinocerites and Aedes- Haemagogus clades occupied increasingly derived positions in the molecular phylogeny. An intron present in the Culicinae- Toxorhynchitinae lineage and one outgroup taxon was absent in the basal Anophelinae lineage and the second outgroup taxon, suggesting that intron insertions or deletions may not always be reliable systematic characters.      

Evaluation of the prevalence and economic burden of adverse drug reactions presenting to the medical emergency department of a tertiary referral centre: a prospective study

Background  

Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India     

A novel mechanism of autophagic cell death in dystrophic muscle regulated by P2RX7 receptor large-pore formation and HSP90

P2RX7 is an ATP-gated ion channel, which can also exhibit an open state with a considerably wider permeation. However, the functional significance of the movement of molecules through the large pore (LP) and the intracellular signaling events involved are not known. Here, analyzing the consequences of P2RX7 activation in primary myoblasts and myotubes from the Dmd^mdx mouse model of Duchenne muscular dystrophy, we found ATP-induced P2RX7-dependent autophagic flux, leading to CASP3-CASP7-independent cell death. P2RX7-evoked autophagy was triggered by LP formation but not Ca²⁺ influx or MAPK1-MAPK3 phosphorylation, 2 canonical P2RX7-evoked signals. Phosphoproteomics, protein expression inference and signaling pathway prediction analysis of P2RX7 signaling mediators pointed to HSPA2 and HSP90 proteins. Indeed, specific HSP90 inhibitors prevented LP formation, LC3-II accumulation, and cell death in myoblasts and myotubes but not in macrophages. Pharmacological blockade or genetic ablation of p2rx7 also proved protective against ATP-induced death of muscle cells, as did inhibition of autophagy with 3-MA. The functional significance of the P2RX7 LP is one of the great unknowns of purinergic signaling. Our data demonstrate a novel outcome—autophagy—and show that molecules entering through the LP can be targeted to phagophores. Moreover, we show that in muscles but not in macrophages, autophagy is needed for the formation of this LP. Given that P2RX7-dependent LP and HSP90 are critically interacting in the ATP-evoked autophagic death of dystrophic muscles, treatments targeting this axis could be of therapeutic benefit in this debilitating and incurable form of muscular dystrophy.     

The Endoplasmic Reticulum Chaperone BiP/GRP78 Is Important in the Structure and Function of the Human Cytomegalovirus Assembly Compartment

We previously demonstrated that the endoplasmic reticulum (ER) chaperone BiP functions in human cytomegalovirus (HCMV) assembly and egress. Here, we show that BiP localizes in two cytoplasmic structures in infected cells. Antibodies to the extreme C terminus, which includes BiP''s KDEL ER localization sequence, detect BiP in regions of condensed ER near the periphery of the cell. Antibodies to the full length, N terminus, or larger portion of the C terminus detect BiP in the assembly compartment. This inability of C-terminal antibodies to detect BiP in the assembly compartment suggests that BiP''s KDEL sequence is occluded in the assembly compartment. Depletion of BiP causes the condensed ER and assembly compartments to dissociate, indicating that BiP is important for their integrity. BiP and pp28 are in association in the assembly compartment, since antibodies that detect BiP in the assembly compartment coimmunoprecipitate pp28 and vice versa. In addition, BiP and pp28 copurify with other assembly compartment components on sucrose gradients. BiP also coimmunoprecipitates TRS1. Previous data show that cells infected with a TRS1-deficient virus have cytoplasmic and assembly compartment defects like those seen when BiP is depleted. We show that a fraction of TRS1 purifies with the assembly compartment. These findings suggest that BiP and TRS1 share a function in assembly compartment maintenance. In summary, BiP is diverted from the ER to associate with pp28 and TRS1, contributing to the integrity and function of the assembly compartment.Human cytomegalovirus (HCMV), the largest of the human herpesviruses, is capable of encoding over 200 proteins, which are expressed in temporal fashion as immediate-early, early, delayed-early, and late genes. Despite the extensive coding capacity of HCMV, its replication cycle is slow. During this protracted period, the virus must maintain optimal replication conditions in the host cell. However, the increasing strain of the infection induces cellular stress responses with consequences that may be deleterious to the progress of the infection. We and others have previously shown that HCMV has multiple mechanisms to deal with the deleterious aspects of cellular stress responses while maintaining beneficial ones (2, 8-10, 14, 17, 18, 22-24, 26, 27, 50, 51).An example of these mechanisms is the viral control of endoplasmic reticulum (ER) stress and the unfolded protein response (UPR). Due to the number of HCMV proteins that are glycosylated, or receive other ER-dependent posttranslational modifications, the load of proteins in the ER can exceed its capacity, resulting in ER stress and the activation of the UPR (18, 47, 51). However, we and others have shown that HCMV controls and modulates the UPR, maintaining aspects that may benefit the viral infection while inhibiting aspects that would be detrimental (18, 51).The UPR is normally controlled by transmembrane sensors which initiate the complex UPR signaling cascade when activated by ER stress (reviewed in references 20, 35, 38, and 52). The ER molecular chaperone BiP (immunoglobulin heavy chain-binding protein), also called glucose-regulated protein 78 (GRP78), is believed to bind these sensors and keep them inactive during unstressed conditions. However, when unfolded or misfolded proteins accumulate in the ER, BiP leaves these sensors to perform its chaperone function, thus allowing the sensors to activate UPR signaling. We have previously shown that during HCMV infection, BiP is vastly overproduced (8), suggesting that BiP may have other functions in the viral infection. Indeed, it has been shown that BiP binds to the viral proteins US2 and US11; this interaction is necessary for the virus-mediated degradation of major histocompatibility complex class I and II (15, 47). Further, we have shown that depletion of BiP, using either the BiP-specific subtilase cytotoxin SubAB (32) or short hairpin RNAs, caused infectious virion formation in the cytoplasm to cease and nucleocapsids to accumulate just outside the outer nuclear membrane (8). This result suggested that BiP has a significant role in virion formation and cytoplasmic egress.Although the exact mechanism of virion formation in the cytoplasm is not well understood, studies have identified a perinuclear structure, referred to as the cytoplasmic assembly compartment, that is involved in the process. Several viral proteins, for example, tegument proteins (pp28, pp65) (36) and viral glycoproteins (gB, gH, gL, gO, gp65) (36, 46), have been identified as part of this structure. Defining the exact origin of this compartment has been complicated by the observation of specific organellar markers in and around the compartment, while other markers of the same organelles are not detected. For example, immunofluorescence examination suggests that the early endosomal marker early endosome antigen 1 (EEA1) has been observed in the center of the assembly compartment (12, 13); however, Rab4 and Rab5, other early endosomal markers, were not detected (16). Such observations suggest that the virus directs specific viral and cellular proteins to the assembly compartment as needed for assembly compartment function.In the present study, we further examine the role of BiP during an HCMV infection, including its localization and interactions with other proteins. We show here that in infected cells, BiP localizes in two distinct structures, regions of condensed ER near the periphery of the cell and the assembly compartment. The data suggest that BiP diversion from the ER to the assembly compartment is due to occlusion of its ER localization signal. Depletion of BiP causes both condensed ER and assembly compartments to disperse, indicating that BiP is important for their formation or maintenance. BiP and pp28 appear to associate in the assembly compartment, since BiP from the assembly compartment coimmunoprecipitates pp28 and vice versa. In addition, both BiP and pp28 copurify with the assembly compartment on sucrose gradients. BiP also coimmunoprecipitates TRS1. Previous studies (1, 4) have shown that cells infected with HCMV with a mutation in the TRS1 gene show cytoplasmic and assembly compartment defects like those seen when BiP is depleted (reference 8 and the studies presented below). We show that a fraction of TRS1 purifies with the assembly compartment, indicating a shared assembly compartment function with BiP. In summary, our data suggest that BiP is diverted from the ER to associate with pp28 and TRS1, contributing to the integrity and function of the assembly compartment.