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Drought‐stress and plant resistance affect herbivore performance and proteome: the case of the green peach aphid Myzus persicae (Hemiptera: Aphididae) 下载免费PDF全文
Jaime A. Verdugo Marie‐Helene Sauge Jean‐Philippe Lacroze Frederic Francis Claudio C. Ramirez 《Physiological Entomology》2015,40(4):265-276
Little is known about the simultaneous effects of drought stress and plant resistance on herbivorous insects. By subjecting the green peach aphid Myzus persicae Sulzer to well‐watered and drought‐stressed plants of both susceptible and resistant peach (Prunus persica), the effects of both stressors on aphid performance and proteomics are tested. Overall, the influence of the water treatment on aphid performance is less pronounced than the effect of host plant genetic resistance. On the susceptible cultivar, aphid survival, host acceptance and ability to colonize the plant do not depend on water treatment. On the resistant cultivar, aphid survival and ability to colonize are higher on drought‐stressed than on well‐watered plants. A study examining the pattern of protein expression aiming to explain the variation in aphid performance finds higher protein expression in aphids on the drought‐stressed susceptible cultivars compared with the well‐watered ones. In the susceptible cultivar, the regulated proteins are related to energy metabolism and exoskeleton functionality, whereas, in the resistant cultivar, the proteins are involved with the cytoskeleton. Comparison of the protein expression ratios for resistant versus susceptible plants reveals that four proteins are down‐regulated in well‐watered plants and 15 proteins are down‐regulated in drought‐stressed plants. Drought stress applied to the susceptible cultivar induces the regulation of proteins in M. persicae that enable physiological adaptation to maintain an almost unaltered aphid performance. By contrast, for aphids on the resistant cultivar subjected to drought stress, the down‐regulation of proteins responds to an induced host susceptibility effect. 相似文献
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Teresa Casals Maria D. Ramos Javier Giménez Sara Larriba Virginia Nunes X. Estivill 《Human genetics》1997,101(3):365-370
We have analyzed 640 Spanish cystic fibrosis (CF) families for mutations in the CFTR gene by direct mutation analysis, microsatellite haplotypes, denaturing gradient gel electrophoresis, single-strand conformation
analysis and direct sequencing. Seventy-five mutations account for 90.2% of CF chromosomes. Among these we have detected seven
novel CFTR mutations, including four missense (G85V, T582R, R851L and F1074L), two nonsense (E692X and Q1281X) and one splice site mutation
(711+3A→T). Three variants, two in intronic regions (406-112A/T and 3850-129T/C) and one in the coding region (741C/T) were
also identified. Mutations G85V, T582R, R851L, E692X and Q1281X are severe, with lung and pancreatic involvement; 711+3A→T
could be responsible for a pancreatic sufficiency/insufficiency variable phenotype; and F1074L was associated with a mild
phenotype. These data demonstrate the highest molecular heterogeneity reported so far in CF, indicating that a wide mutation
screening is necessary to characterize 90% of the Spanish CF alleles.
Received: 3 July 1997 / Accepted: 20 August 1997 相似文献
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A frameshift mutation (2869insG) in the second transmembrane domain of the CFTR gene: identification, regional distribution, and clinical presentation. 下载免费PDF全文
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Christian Viskov Stefano Elli Elena Urso Davide Gaudesi Pierre Mourier Frederic Herman Christian Boudier Benito Casu Giangiacomo Torri Marco Guerrini 《The Journal of biological chemistry》2013,288(36):25895-25907
The antithrombin (AT) binding properties of heparin and low molecular weight heparins are strongly associated to the presence of the pentasaccharide sequence AGA*IA (ANAc,6S-GlcUA-ANS,3,6S-I2S-ANS,6S). By using the highly chemoselective depolymerization to prepare new ultra low molecular weight heparin and coupling it with the original separation techniques, it was possible to isolate a polysaccharide with a biosynthetically unexpected structure and excellent antithrombotic properties. It consisted of a dodecasaccharide containing an unsaturated uronate unit at the nonreducing end and two contiguous AT-binding sequences separated by a nonsulfated iduronate residue. This novel oligosaccharide was characterized by NMR spectroscopy, and its binding with AT was determined by fluorescence titration, NMR, and LC-MS. The dodecasaccharide displayed a significantly increased anti-FXa activity compared with those of the pentasaccharide, fondaparinux, and low molecular weight heparin enoxaparin. 相似文献
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One of the potential explanations for negative compatibility effects (NCE) in subliminal motor priming tasks has been perceptual prime-target interactions. Here, we investigate whether the characteristic tri-phasic LRP pattern associated with the NCE is caused by these prime-target interactions. We found that both the prime-related phase and the critical reversal phase remain present even on trials where the target is omitted, confirming they are elicited by the prime and mask, not by prime-target interactions. We also report that shape and size of the reversal phase are associated with response speed, consistent with a causal role for the reversal for the subsequent response latency. Additionally, we analysed sequential modulation of the NCE by previous conflicting events, even though such conflict is subliminal. In accordance with previous literature, this modulation is small but significant. 相似文献
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T Okuno J Casals K H Kim D W Walton H K Shin 《Japanese journal of medical science & biology》1976,29(4):187-197
In the light of recent knowledge on a complex of diseases caused by a new group of viruses, arenaviruses, virological studies largely directed toward small field mammals were undertaken during 1973-1974 aiming at etiological clarification of Korean hemorrhagic nephrosonephritis (KHNN). Specimens were collected in an endemic area of KHNN located north to northeast of Seoul. Virus isolation tests with 299 urine specimens and 131 mite pools recovered from small mammals and 14 acute stage sera from typical cases yielded negative results. Complement-fixation (CF) tests failed to detect antibodies against the antigens of Congo, lymphocytic choriomeningitis (LCM), Tacaribe, and Pichinde viruses among 366 small mammal sera. In addition, CF tests of 59 of the above sera against Apoi and Lassa virus antigens were negative. The results do not support the likelihood of an arenavirus being transmitted among Korean small field mammals, the overwhelming majority of which were Apodemus agrarius. A hypothesis that KHNN is caused by a virus of small field mammal origin was not proved within the technical limit of relatively unsophisticated methods employed herein. 相似文献
10.
Advantage Provided by Iron for Escherichia coli Growth and Cultivability in Drinking Water 下载免费PDF全文
Brice M. R. Appenzeller Carolina Ya?ez Frederic Jorand Jean-Claude Block 《Applied microbiology》2005,71(9):5621-5623
The presence of iron, used both as a nutrient and as an electron acceptor, was demonstrated to give an advantage to Escherichia coli bacteria in drinking water. Slight additions of ferrous sulfate to water with initial low iron concentrations led to a significant increase in the number of E. coli bacteria. The presence of ferric oxide in water under anaerobic conditions increased bacterial cultivability. 相似文献