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991.
Ikram Zaïdi Chantal Ebel Majdi Touzri Etienne Herzog Jean-Luc Evrard Anne Catherine Schmit Khaled Masmoudi Moez Hanin 《Plant molecular biology》2010,73(3):325-338
The regulation of plant signalling responses by Mitogen-Activated Protein Kinases (MAPKs)-mediated protein phosphorylation is well recognized. MAP kinase phosphatases (MKPs) are negative regulators of MAPKs in eukaryotes. We report here the identification and the characterization of TMKP1, the first wheat MKP (Triticum turgidum L. subsp. Durum). Expression profile analyses performed in two durum wheat cultivars showing a marked difference in salt and drought stress tolerance, revealed a differential regulation of TMKP1. Under salt and osmotic stress, TMKP1 is induced in the sensitive wheat variety and repressed in the tolerant one. A recombinant TMKP1 was shown to be an active phosphatase and capable to interact specifically with two wheat MAPKs (TMPK3 and TMPK6). In BY2 tobacco cells transiently expressing GFP::TMKP1, the fusion protein was localized into the nucleus. Interestingly, the deletion of the N-terminal non catalytic domain results in a strong accumulation of the truncated fusion protein in the cytoplasm. In addition, when expressed in BY2 cells, TMPK3 and TMPK6 fused to red fluorescent protein (RFP) were shown to be present predominantly in the nucleus. Surprisingly, when co-expressed with the N-terminal truncated TMKP1 fusion protein; both kinases are excluded from the nuclear compartment and accumulate in the cytoplasm. This strongly suggests that TMKP1 interacts in vivo with TMPK3 and TMPK6 and controls their subcellular localization. Taken together, our results show that the newly isolated wheat MKP might play an active role in modulating the plant cell responses to salt and osmotic stress responses. 相似文献
992.
993.
The acoustic structure of echolocation pulses emitted by Japanese pipistrellePipistrellus abramus (Temminck, 1840) bats during different phases of aerial hawking is described here for the first time. Behavioural observations
of the foraging flight in conjunction with acoustical analysis of echolocation pulses indicated a flight path consisting of
four distinct phases following the reconnaissance or search phase. Short (∼4.68 ms) and relatively broadband frequencymodulated
(FM) pulses (∼23.55 kHz bandwidth) were emitted at a repetition rate of 15 Hz during presumed target approach. Presumed insect
capture consisted of an early and a late buzz phase. Both buzz types were emitted at high repetition rates (111 Hz in early
to 222 Hz in late) and consisted of very short, broadband FM pulses (1.26 ms in early to 0.3 ms in late). There was also a
characteristically sharp drop in both the peak and terminal frequencies of each echolocation pulse during the transition from
early to late buzz. No pulses were recorded during the final phase of foraging referred to as a “post-buzz pause”. Thus the
foraging behaviour of this species consisted of five sequential phases involving four broad types of echolocation pulses. 相似文献
994.
Romain Pigeaud Valérie Plagnes Jean-Jacques Bahain Sylvie Demailly Éric Laval Joël Rodet Philippe Walter avec la collaboration de Pascal Bonic et Gabriel Renault du groupe des Excentriques et J.-J. Chaut de la Société française pour l’Étude et la Protection des Mammifères 《L'Anthropologie》2010,114(1):97
Since 1998, a multidisciplinary team works on the study of the representations in the cave Mayenne-Sciences (Thorigné-en-Charnie, Mayenne). Particularly, there are trials for U-TH (TIMH) datations of the speleothems recovering the drawings and fossils of the bats; this would help to know at what date the decorated cave was closed. The studies already allowed to know better the black drawings, executed with a wooden charcoal crayon. Thus, it was possible to make removals which gave two dates from the Gravettian phase; this feeds again the discussion about the chronocultural position of this cave, on of the most septentrional caves we know. 相似文献
995.
996.
Morphological and molecular analyses demonstrate that Coniolariella gamsii and Coniolaria murandii are distinct species. The latter species is validated here as Coniolariella macrothecia. A key to the five species of the genus is provided. 相似文献
997.
Induced plant resistance (IR) against pathogen infection can be triggered by various chemical and biological elicitors. The effectiveness of elicitors to induce resistance as a practical means to control plant disease makes use of the plant’s own defence mechanisms triggered by resistance inducing agents. The aim of the present study was to examine the possible side effects of IR on the establishment and the efficiency of a rhizobial symbioses (Bradyrhizobium japonicum-soybean) and an arbuscular mycorrhizal symbioses (Glomus mosseae —soybean). IR was triggered by applying, acibenzolar S-methyl (ASM) at 80 mg a.i. L?1 by two ways: seed soaking or foliar spray. Chitinase activity, used as a biochemical marker of IR, increased when ASM was applied both as seed soaking or as foliar spray. In vitro ASM showed no direct effect on the growth of B. japonicum and induced, only at a high concentration, a slight inhibition effect on spore germination of G. mosseae. ASM caused after both treatments a significant decrease in the number of nodules. Nitrogen content in aerial parts and roots decreased. On the other hand, ASM showed no significant effect on the frequency of colonization by G.mosseae but reduced the intensity of colonization and the proportion of arbuscules. The possible interaction between IR and the induction and suppression of defence-like mechanisms during symbiotic processes is discussed. 相似文献
998.
McGillicuddy EA Chaar CI Flynn C Villalona G Longo WE 《The Yale journal of biology and medicine》2010,83(3):113-117
Although the medical management of fistulizing Crohn's disease is improving, a subset of patients does not respond to maximal medical therapy and is referred for surgical consultation. We report a case of Crohn's colitis with an ingested foreign body resulting in a cologastric fistula. The patient underwent segmental colectomy and takedown of the cologastric fistula. At the time of laparotomy, the foreign body was found in the fistulous colonic segment. The presence of an ingested foreign body likely contributed to a rare fistula that was refractory to medical management. 相似文献
999.
Laurence Goffin Queralt Seguin-Estévez Montserrat Alvarez Walter Reith Carlo Chizzolini 《Arthritis research & therapy》2010,12(2):R73
Introduction
Extracellular matrix (ECM) turnover is controlled by the synthetic rate of matrix proteins, including type I collagen, and their enzymatic degradation by matrix metalloproteinases (MMPs). Fibrosis is characterized by an unbalanced accumulation of ECM leading to organ dysfunction as observed in systemic sclerosis. We previously reported that proteasome inhibition (PI) in vitro decreases type I collagen and enhances MMP-1 production by human fibroblasts, thus favoring an antifibrotic fibroblast phenotype. These effects were dominant over the pro-fibrotic phenotype induced by transforming growth factor (TGF)-β. Here we investigate the molecular events responsible for the anti-fibrotic phenotype induced in fibroblasts by the proteasome inhibitor bortezomib. 相似文献1000.
The cotton plant, Gossypium hirsutum, hosts various pests that damage different structures. Among these pests, Spodoptera cosmioides (Walker) and Spodoptera eridania (Cramer) (Lepidoptera: Noctuidae) are considered important. The objectives of this study were to characterize and to quantify the potential damage of S. eridania and S. cosmioides feeding on different structures of cotton plants. For this purpose, newly-hatched larvae were reared on the following plant parts: leaf and flower bud; leaf and boll; flower bud or boll; and leaf, flower bud and boll. The survival of S. cosmioides and S. eridania was greater than 80% and 70% for larvae fed on cotton plant parts offered separately or together, respectively. One larva of S. eridania damaged 1.7 flower buds, but did not damage bolls, while one larva of S. cosmioides damaged 5.2 flower buds and 3.0 cotton bolls. Spodoptera eridania and S. cosmioides can be considered species with potential to cause economic damage to cotton plants because they can occur throughout cotton developmental stages causing defoliation and losses of reproductive structures. Therefore, the results validate field observations that these two species of Spodoptera are potential pests for cotton. 相似文献