Localization of the Major NF-κB-activating Site and the Sole TRAF3 Binding Site of LMP-1 Defines Two Distinct Signaling Motifs

The TRAF3 molecule interacts with the cytoplasmic carboxyl terminus (COOH terminus) of the Epstein-Barr virus-encoded oncogene LMP-1. NF-κB activation is a downstream signaling event of tumor necrosis factor receptor-associated factor (TRAF) molecules in other signaling systems (CD40 for example) and is an event caused by LMP-1 expression. One region capable of TRAF3 interaction in LMP-1 is the membrane-proximal 45 amino acids (188–242) of the COOH terminus. We show that this region contains the only site for binding of TRAF3 in the 200-amino acid COOH terminus of LMP-1. The site also binds TRAF2 and TRAF5, but not TRAF6. TRAF3 binds to critical residues localized between amino acids 196 and 212 (HHDDSLPHPQQATDDSG), including the PXQX(T/S) motif, that share limited identity to the CD40 receptor TRAF binding site (TAAPVQETL). Mutation of critical residues in the TRAF3 binding site of LMP-1 that prevents binding of TRAF2, TRAF3, and TRAF5 does not affect NF-κB-activating potential. Deletion mapping localized the major NF-κB activating region of LMP-1 to critical residues in the distal 4 amino acids of the COOH terminus (383–386). Therefore, TRAF3 binding and NF-κB activation occur through two separate motifs at opposite ends of the LMP-1 COOH-terminal sequence

Control of the Onset of Filamentation in Condensed Media

Propagation of intense, ultrashort laser pulses through condensed media like crystals of BaF$_2$ and sapphire results in the formation of filaments. We demonstrate that the onset of filamentation may be controlled by rotating the plane of polarization of incident light. We directly visualize filamentation in BaF_2 via six-photon absorption-induced fluorescence and, concomitantly, by probing the spectral and spatial properties of white light that is generated.Comment: To appear in Phys. Rev.

Ecology of Juvenile Walleye Pollock, Theragra chalcogramma: Papers from the workshop "The Importance of Prerecruit Walleye Pollock to the Bering Sea and North Pacific Ecosystems" Seattle, Washington, 28-30 October 1993

The Alaska Fisheries Science Center (AFSC), National Marine Fisheries Service (NMFS), hosted an international workshop, 'The Importance of Prerecruit Walleye Pollock to the Bering Sea and North Pacific Ecosystems," from 28 to 30 October 1993. This workshop was held in conjunction with the annual International North Pacific Marine Science Organization (PICES) meeting held in Seattle. Nearly 100 representatives from government agencies, universities, and the fishing industry in Canada, Japan, the People's Republic of China, Russia, and the United States took part in the workshop to review and discuss current knowledge on juvenile pollock from the postlarval period to the time they recruit to the fisheries. In addition to its importance to humans as a major commercial species, pollock also serves as a major forage species for many marine fishes, birds, and mammals in the North Pacific region. (PDF file contains 236 pages.

Egg parasitoid exploitation of plant volatiles induced by single or concurrent attack of a zoophytophagous predator and an invasive phytophagous pest

Zoophytophagous insect predators can induce physiological responses in plants by activating defence signalling pathways, but whether plants can respond to facultative phytophagy by recruiting natural enemies remains to be investigated. In Y-tube olfactometer bioassays, using a system including a Vicia faba plant, the zoophytophagous predator Podisus maculiventris and the egg parasitoid Telenomus podisi, we first demonstrated that T. podisi females are attracted by broad bean plants damaged by feeding activity of P. maculiventris and on which host egg masses had been laid, while they are not attracted by undamaged plants or plants damaged by feeding activity alone. In a second experiment, we evaluated the impact of the invasive phytophagous pest Halyomorpha halys on this plant volatile-mediated tritrophic communication. Results showed that the invasive herbivorous adults do not induce plants to recruit the native egg parasitoid, but they can disrupt the local infochemical network. In fact, T. podisi females are not attracted by volatiles emitted by plants damaged by H. halys feeding alone or combined with oviposition activity, nor are they attracted by plants concurrently infested by P. maculiventris and H. halys, indicating the specificity in the parasitoid response and the ability of the invasive herbivore in interrupting the semiochemical communication between plants and native egg parasitoids. To the best of our knowledge, this is the first study showing that zoophytophagous predator attacks induce indirect plant defences similarly to those defence strategies adopted by plants as a consequence of single or concurrent infestations of herbivorous insects

The Mah Jongg Nightmare

Sheet music contains anti-Asian racist language, stereotypes, and/or imagry.https://digitalcommons.library.umaine.edu/mmb-vp/6871/thumbnail.jp

Effet des taches foliaires causées par le Phaeosphaeria nodorum inoculé à différents stades de développement sur le rendement du blé de printemps

Des études en serre ont été réalisées pour évaluer l'effet du Phaeosphaeria nodorum sur le rendement du blé de printemps (Triticum aestivum, cv. Laval 19). Les plants de blé étaient inoculés aux stades gonflement épiaison, pleine floraison et grain laiteux. L'essai a été réalisé au cours de l'hiver 1993 et répété au cours de l'hiver 1994. L'inoculation du champignon pathogène P. nodorum entraîne généralement une augmentation significative de la surface foliaire infectée et une réduction du rendement comparativement aux témoins non inoculés. La surface foliaire infectée mesurée uniquement sur la feuille étendard est similaire à celle mesurée sur la plante entière. Le stade phénologique a un effet significatif sur toutes les variables observées: surface foliaire infectée, poids des tiges et des feuilles, poids des épis, poids des grains, poids des biomasses végétative et totale et indice de récolte. L'inoculation du pathogène au stade grain laiteux, le plus tardif de l'étude, semble avoir provoqué moins d'effets négatifs sur le rendement du blé comparativement aux trois autres stades étudiés. Selon les résultats de cette étude et les observations réalisées au Québec au cours des 15 dernières années, il est peu probable que les taches foliaires causées par le P. nodorum provoquent des baisses appréciables de rendement du blé de printemps au Québec.Greenhouse studies were carried out to evaluate the effects of foliar leaf spots caused by P. nodorum on spring wheat (Triticum aestivum, cv. Laval 19) yield. Wheat plants were inoculated at booting, heading, flowering and milking growth stages. Experiments were first performed in winter 1993 and repeated in winter 1994. Inoculation of P. nodorum usually resulted in an increase of leaf spots and a decrease of yield compared to uninoculated plants. Foliar flag leaves spots were similar to total plant foliar leaf spots. All variables were significantly affected by inoculation stages : infected foliar area, biomass of straw and leaves, biomass of spikes, biomass of grains, vegetative biomass and harvest index. Inoculation at milking growth stage seemed to resul in the least negative impacts on yield compared to all other stages. From the results of this study and observations performed in Quebec during the 15 past years, leaf spots caused by P. nodorum should not resul in important spring wheat yield losses in Quebec

Mid-Western Educational Researcher Call for Papers: Special Issue on Anti-Racist Education

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Effects of a Large Fishing Closure on Benthic Communitites in the Western Gulf of Maine: Recovery from the Effects of Gillnets and Otter Trawls

The recovery of benthic communities inside the western Gulf of Maine fishing closure area was evaluated by comparing invertebrate assemblages at sites inside and outside of the closure four to six years after the closure was established. The major restriction imposed by the closure was a year-round prohibition of bottom gillnets and otter trawls. A total of 163 seafloor sites (~half inside and half outside the closure) within a 515-km2 study area were sampled with some combination of Shipek grab, Wildco box corer, or underwater video. Bottom types ranged from mud (silt and clay) to boulders, and the effects of the closure on univariate measures (total density, biomass, taxonomic richness) of benthos varied widely among sediment types. For sites with predominantly mud sediments, there were mixed effects on inside and outside infauna and no effect on epifauna. For sites with mainly sand sediments, there were higher density, biomass, and taxonomic richness for infauna inside the closure, but no significant effects on epifauna. For sites dominated by gravel (which included boulders in some areas), there were no effects on infauna but strong effects on epifaunal density and taxonomic richness. For fishing gear, the data indicated that infauna recovered in sand from the impacts of otter trawls operated inside the closure but that they did not recover in mud, and that epifauna recovered on gravel bottoms from the impact of gillnets used inside the closure. The magnitudes of impact and recovery, however, cannot be inferred directly from our data because of a confounding factor of different fishing intensities outside the closure for a direct comparison of preclosure and postclosure data. The overall negative impact of trawls is likely underestimated by our data, whereas the negative impact of gillnets is likely overestimated

Light Filaments Without Self Guiding

An examination of the propagation of intense 200 fs pulses in water reveals light filaments not sustained by the balance between Kerr-induced self-focusing and plasma-induced defocusing. Their appearance is interpreted as the consequence of a spontaneous reshaping of the wave packet form a gaussian into a conical wave, driven by the requirement of maximum localization, minimum losses and stationarity in the presence of non-linear absorption.Comment: Submitted to Phys. Rev. Lett. on July 7th, 200