ABSTRACT Junonia coenia densovirus (JcDNV) is an ambisense insect parvovirus highly pathogenic for lepidopteran pests at larval stages. The potential use of DNVs as biological control agents prompted us to reinvestigate the host range and cellular mechanisms of infection. In order to understand the early events of infection, we set up a functional infection assay in a cell line of the pest Lymantria dispar to determine the intracellular pathway undertaken by JcDNV to infect a permissive lepidopteran cell line. Our results show that JcDNV particles are rapidly internalized into clathrin-coated vesicles and slowly traffic within early and late endocytic compartments. Blocking late-endocytic trafficking or neutralizing the pH with drugs inhibited infection. During internalization, disruption of the cytoskeleton, and inhibition of phosphatidylinositol 3-kinase blocked the movement of vesicles containing the virus to the nucleus and impaired infection. In summary, our results define for the first time the early endocytic steps required for a productive DNV infection.

Xanthogaleruca luteola Müller (Coleoptera, Chrysomelidae) is widely spread in Europe and North America and it is a dangerous pest of elm-trees. In Italy the elm-trees are often located in urban areas so the potential of 3 entomoparasitic nematodes (EPNs; 2 Italian strains of Steinernema carpocapsae and S. feltiae and 1 commercial strain of Heterorhabditis bacteriophora), was evaluated through field experiments for control of X. luteola. During the first 2 weeks of June 2006, S. carpocapsae (ItS-MR7), S. feltiae (ItS-CL2) and H. bacteriophora (Nematop®) in gel suspensions (with Idrosorb SR 200 and Xanthan gum) were sprayed on leaves and small branches heavily infested by X. luteola larvae in a periurban park of Bari city (Apulia Region, South Italy). The efficiency of these EPNs was then evaluated after 3 and 5 days. S. carpocapsae in Idrosorb + Xanthan gum controlled 67% of the larvae after 5 days, producing significantly greater larval mortality than S. feltiae and H. bacteriophora. Cultivation conditions of biocomplexes applicable to control Melolontha melolontha C. Sisak, Z. Kaskötő, T. Tóth, T. Lakatos ................................................................... 297 Abstract: Recently several nematode/bacterium complexes have been isolated in Hungary with potential to grubs of the European cockchafer (Melolontha melolontha). The cultivation of one of the most promising biocomplexes, Heterorhabditis downesi ’267’ + Photorhabdus temperata in liquid medium can be considered to be effective if the concentration of the dauer juveniles achieves 10,000/ml. A prerequisite for the elaboration of suitable conditions for cultivation is the development of optimal process conditions (aeration at low shear stress, medium composition, etc.) and to avoid the occurrence of phase variants of the bacterium symbiont. Cultivation experiments with P. temperata were performed first in shake flasks, in LB and TSY medium at 20-22°C. The aeration rate required by the cells during the logarithmic growth period was about 0.6-0.7 vvm. Applying a 5 litre mechanically stirred fermenter equipped with drafttube for bacterium growth studies, a special fedbatch technique has been elaborated. Cell numbers of the primary phase variant were sustained at high numbers over a period of 19 days. Medium optimization studies exchanged several protein components of LCM for lipid components and obtained considerably higher numbers of dauer juveniles and hermaphrodites. Rape seed oil was the most suitable lipid component. In the best medium, the initial nematode dauer juvenile number (1,000/ml) increased to 120,000/ml within 12 days. At present, scale-up studies of the biocomplex are in progress in column bioreactors of different type. Recovery of Steinernema carpocapsae and Steinernema feltiae in liquid culture A. Hirao, R.-U. Ehlers ................................................................................................. 301 Abstract: The development from infective Dauer juvenile (DJ) to third stage juvenile, so called “recovery”, occurs at almost 100% when DJs infect a living insect. In contrast, recovery is much lower, when DJs are inoculated in liquid culture media, in which the symbiotic bacteria were preincubated. For the purpose of obtaining an increase in recovery in liquid culture, recovery inducing factor for S. carpocapsae and S. feltiae was investigated. The influence of penetration behavior on recovery was checked. DJs injected into G. mellonella or inoculated into sand containing the insect recovered at almost 100%. The penetration activity is excluded to influence recovery of S. carpocapsae and S. feltiae. The high recovery in insects might to be due to a food signal present in the serum of G. mellonella. Inoculation of DJs in purified and antibiotics-treated serum was investigated. Whereas in vivo recovery of S. carpocapsae reached 100%, only 40% of S. feltiae recovered in sterilize serum. Whereas a food signal triggering recovery of S. carpocapsae is found in the serum, the composition of the G. mellonella serum seems suboptimal for recovery of S. feltiae. The influence of the density of the symbiotic bacteria, X. nematophila and X. bovienii (isolated from S. carpocapsae and S. feltiae, respectively) was investigated. The bacteria were proliferated in liquid medium for 36 and 48 hours. Then DJs at a density of 1,000 DJs/ml were inoculated at bacterial densities of 108, 109 and 1010 cells/ml. Recovery of S. carpocapsae was checked every two hours until 12 h post inoculation (hpi) and S. feltiae every two hours between 4 and 10 hpi. Comparing recovery at different bacterial densities, recovery of both nematodes increased with increasing bacterial density. However, the recovery of S. feltiae was delayed and lower compared to results obtained with S. carpocapsae. Culture supernatant of both bacterial symbionts contained food signal, however, the recovery was significantly higher when bacterial cells were present. Differential gene expression of recovery in Heterhorabditis bacteriophora A. Moshayov, H. Koltai, I. Glazer (Abstract only) ......................................................... 307 Expression of different desiccation tolerance related genes in various species of entomopathogenic nematodes V. S. Somvanshi, H. Koltai, I. Glazer (Abstract only) ................................................... 308 Genetic improvement of beneficial traits mixed population of Steinernema feltiae for enhancement of persistence and efficacy M. Chubinishvili, L. Salame, C. Chkhubianishvili, I. Glazer (Abstract only) ................. 309 Soil insect pests and miscellaneous When should we use biocontrol agents against leatherjackets (Tipula paludosa Meig.) R.P.Blackshaw ........................................................................................................... 313 Abstract: Recent work has demonstrated that biological control agents directed against the larvae of Tipula paludosa (leatherjackets) are more effective if applied against early instars in October rather than later instars in the late winter/early spring. In this paper simulation modelling is used to identify potential strategies for the deployment of biocontrol agents against leatherjackets in continuous grass, and in grass/arable rotations. It is concluded that the optimal prophylactic strategy in continuous grass lies between annual and biannual application frequencies, and that application in the autumn preceding cultivation for a spring crop suppresses populations better than applications earlier in the rotation. A decision tool based on economic thresholds is presented for grass/arable rotations. The results are discussed and it is concluded that development of a robust monitoring system is necessary if recommendations other than prophylactic applications are to be made. Biocontrol of Capnodis tenebrionis (L.) (Col., Buprestidae) with entomopathogenic fungi P. Marannino, C. Santiago Álvarez, E. de Lillo, E. Tarasco, O. Triggiani, E. Quesada Moraga ........................................................................................................ 319 Abstract: A study was carried out at ETSIAM to investigate the potential of Beauveria bassiana (Bals.) Vuill. and Metarhizium anisopliae (Metsch.) Sorok. for the control of the peach root-borer, Capnodis tenebrionis (L.), a major threat to stone-fruit orchards in several Mediterranean countries. The pathogenicity of 4 B. bassiana and 4 M. anisopliae isolates (from ETSIAM collection) against C. tenebrionis neonate larvae was assessed under endophytic conditions. Mortality rates varied from 23.5 to 100%, 10 days after inoculation by dipping in a suspension with 108 conidia/ml. The most virulent isolate, M. anisopliae EAMa 01/58-Su, was used as spore suspension (106, 107, 108 conidia/ml) for soil application on Prunus myrobalana Lois. potted seedlings 2 days before infesting them with C. tenebrionis neonates. The treatment caused a significant mortality (83.3 to 91.6%) on the larvae recovered from the roots 4 weeks later. No significant difference was detected among the doses. The susceptibility of C. tenebrionis adults to EAMa 01/58-Su was also assessed and a significant mortality (86.7%) was ascertained after immersion in a spore suspension (108 conidia/ml). No significant difference was pointed out between male and female mortalities. The effectiveness of the selected M. anisopliae isolate was proved also using non-woven fiber bands impregnated with conidia. Mortality of beetles that crossed the band varied from 85.7 to 100%. No significant correlation was found between time needed to cross the band and survival times. Our results demonstrate that EAMa 01/58Su is suitable to target successfully both peach-borer stages. Infectivity of Steinernema feltiae and Heterorhabditis bacteriophora towards first and second stage larvae of the forest cockchafer, Melolontha hippocastani K. Jung, A. Peters, J. Pelz .......................................................................................... 327 Abstract: At high population densities, the forest cockchafer, Melolontha hippocastani is a serious pest insect causing death to trees and seedlings. In the southern Rhine valley of Germany, a new gradation of M. hippocastani has built up since the 1980s. Despite considerable results on the control of grubs with entomopathogenic nematodes (EPN), so far no nematode was identified, which efficiently infect Melolontha spp. We herein report on laboratory assays with H. bacteriophora and S. feltiae, both alone, in combination with one another and with B. brongniartii against the 1st and 2nd instar larvae of M. hippocastani. First instar larvae did not seem to be more susceptible than second instar larvae. None of the nematode, alone or in combination caused high mortality, with H. bacteriophora being a little better than S. feltiae (28 compared to 4 % at 500.000 IJ’s/m2). In conclusion, the nematodes currently availa

ABSTRACT Hydroxychloroquine at 1 μM reduces the load of human immunodeficiency virus type 1 (HIV-1) in patients, whereas chloroquine (CQ) concentrations above 3 μM are required for inhibition of HIV-1 replication in peripheral blood mononuclear cells. Exogenous HIV-1 Tat reaches the cytosol of T cells by using low endosomal pH, and endosome neutralization by CQ prevents Tat from entering and affecting T cells. We show here that 0.6 μM CQ inhibits cytokine secretion induced by Tat in monocytes without affecting lipopolysaccharide-triggered cytokine release. This finding suggests that the in vivo anti-HIV-1 effect of CQ results not from a direct effect on the infected cell but rather from the capacity of CQ to prevent Tat from perturbing the cytokine balance.

The HIV-1 Tat protein is secreted by infected cells. Extracellular Tat can affect bystander uninfected T cells and induce numerous biological responses such as apoptosis and cytokine secretion. Tat is likely involved in several immune disorders during AIDS. Nevertheless, it is not known whether Tat triggers cell responses directly upon binding to signaling receptors at the plasma membrane or after delivery to the cytosol. The pathway that enables Tat to reach the cytosol is also unclear. Here we visualized Tat within T-cell-coated pits and endosomes. Moreover, inhibitors of clathrin/AP-2-mediated uptake such as chlorpromazine, activated RhoA, or dominant-negative mutants of Eps15, intersectin, dynamin, or rab5 impaired Tat delivery to the cytosol by preventing its endocytosis. Molecules neutralizing low endosomal pH or Hsp90 inhibitors abolished Tat entry at a later stage by blocking its endosomal translocation, as directly shown using a cell-free translocation assay. Finally, endosomal pH neutralization prevented Tat from inducing T-cell responses such as NF-kappaB activation, apoptosis, and interleukin secretion, indicating that cytosolic delivery is required for Tat signaling. Hence, Tat enters T cells essentially like diphtheria toxin, using clathrin-mediated endocytosis before low-pH-induced and Hsp90-assisted endosomal translocation. Cell responses are then induced from the cytosol.

Biology of the CellVolume 91, Issue 7 p. 562-562a HIV-TAT is endocytosed by uninfected lymphocytes before triggering their apoptosis Agnès Vendeville, Agnès Vendeville UMR 5539 CNRS, Dept Biologie-Santé, Université Montpellier II, 34095 MONTPELLIER, FranceSearch for more papers by this authorNadir Bettache, Nadir Bettache UMR 5539 CNRS, Dept Biologie-Santé, Université Montpellier II, 34095 MONTPELLIER, FranceSearch for more papers by this authorBruno Beaumelle, Bruno Beaumelle UMR 5539 CNRS, Dept Biologie-Santé, Université Montpellier II, 34095 MONTPELLIER, FranceSearch for more papers by this author Agnès Vendeville, Agnès Vendeville UMR 5539 CNRS, Dept Biologie-Santé, Université Montpellier II, 34095 MONTPELLIER, FranceSearch for more papers by this authorNadir Bettache, Nadir Bettache UMR 5539 CNRS, Dept Biologie-Santé, Université Montpellier II, 34095 MONTPELLIER, FranceSearch for more papers by this authorBruno Beaumelle, Bruno Beaumelle UMR 5539 CNRS, Dept Biologie-Santé, Université Montpellier II, 34095 MONTPELLIER, FranceSearch for more papers by this author First published: 01 February 2012 https://doi.org/10.1016/S0248-4900(99)90291-5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume91, Issue7September 1999Pages 562-562a RelatedInformation