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101.
Ricardo Oliva Joe Win Sylvain Raffaele Laurence Boutemy Tolga O. Bozkurt Angela Chaparro‐Garcia Maria Eugenia Segretin Remco Stam Sebastian Schornack Liliana M. Cano Mireille van Damme Edgar Huitema Marco Thines Mark J. Banfield Sophien Kamoun 《Cellular microbiology》2010,12(6):705-715
Filamentous pathogens, such as plant pathogenic fungi and oomycetes, secrete an arsenal of effector molecules that modulate host innate immunity and enable parasitic infection. It is now well accepted that these effectors are key pathogenicity determinants that enable parasitic infection. In this review, we report on the most interesting features of a representative set of filamentous pathogen effectors and highlight recent findings. We also list and describe all the linear motifs reported to date in filamentous pathogen effector proteins. Some of these motifs appear to define domains that mediate translocation inside host cells. 相似文献
102.
Throughout the process of pathogen-host co-evolution, viruses have developed a battery of distinct strategies to overcome biochemical and immunological defenses of the host. Thus, viruses have acquired the capacity to subvert host cell apoptosis, control inflammatory responses, and evade immune reactions. Since the elimination of infected cells via programmed cell death is one of the most ancestral defense mechanisms against infection, disabling host cell apoptosis might represent an almost obligate step in the viral life cycle. Conversely, viruses may take advantage of stimulating apoptosis, either to kill uninfected cells from the immune system, or to induce the breakdown of infected cells, thereby favoring viral dissemination. Several viral polypeptides are homologs of host-derived apoptosis-regulatory proteins, such as members of the Bcl-2 family. Moreover, viral factors with no homology to host proteins specifically target key components of the apoptotic machinery. Here, we summarize the current knowledge on the viral modulation of mitochondrial apoptosis, by focusing in particular on the mechanisms by which viral proteins control the host cell death apparatus. 相似文献
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García-Huante Yolanda Cayetano-Cruz Maribel Santiago-Hernández Alejandro Cano-Ramírez Claudia Marsch-Moreno Rodolfo Campos Jorge E. Aguilar-Osorio Guillermo Benitez-Cardoza Claudia G. Trejo-Estrada Sergio Hidalgo-Lara María Eugenia 《Extremophiles : life under extreme conditions》2017,21(1):175-186
Extremophiles - A hyperthermophilic and thermostable xylanase of 82 kDa (TtXynA) was purified from the culture supernatant of T. terrestris Co3Bag1, grown on carboxymethyl cellulose (CMC),... 相似文献
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Leys, used for grazing or production of forage to be conserved as silage or hay, are very important crops in northern areas.
In order to measure the N2 fixation in leys of varying ages and during different parts of the season, detailed measurements were taken of yield, N2 fixation and the amounts of N remaining in the field after harvesting red clover (Trifolium pratense L.)-grass leys at a site in northern Sweden, where they are generally harvested twice per growing season. Entire plants,
including stubble and roots, were sampled at the time of first and second harvest and, in addition, at the end of the growing
season in three neighbouring fields, carrying a first, a second and a third year ley, respectively. N2 fixation was measured by both 15N isotope dilution (ID) and 15N natural abundance (NA) methods. The proportion of clover dry matter (DM) in the stands increased from the first to the second
harvest, but the grasses dominated throughout the entire season, especially below ground. The N concentrations, in both herbage
and whole plants, were about twice as high in the clover as in the grasses. Seasonal variations in N concentrations were minor,
and total N contents followed the same trends as DM. The clover acquired nearly all of its N from N2 fixation: the proportion of N in clover herbage derived from N2 fixation was often >0.8 throughout the season. The variations in the amounts of N2 fixed during the course of the season corresponded well to the seasonal changes in clover biomass. Amounts of fixed N2 allocated to clover herbage during the whole season were in the range 4 to 6 g N m−2 in this unusually rainy year. Calculations of daily N allocation rates to herbage showed that N uptake rates were similar,
and high, in grasses during May–June and July–August, while N2 fixation rates in clover were about 10-fold as high in July–August as in May–June, reflecting the need for N in clover growth.
The proportion of N remaining in clover stubble and roots after the first and second harvests was about 60 and 25%, respectively,
while about 60% of the N in grasses remained in stubble and roots after both harvests. The considerable amounts of biomass
and N that were left in field after harvesting red clover-grass leys are important for re-growth of the plants and provide
substantial N fertilization for the next crop in the crop rotation. 相似文献
109.
Dysregulation of signaling pathways is believed to contribute to Parkinson's disease pathology and l-DOPA-induced motor complications. Long-lived dopamine (DA) agonists are less likely to cause motor complications by virtue of continuous stimulation of DA receptors. In this study, we compared the effects of the unilateral 6-hydroxydopamine lesion and subsequent treatment with l-DOPA and DA agonist pergolide on signaling pathways in rats. Pergolide caused less pronounced behavioral sensitization than l-DOPA (25 mg/kg, i.p., 10 days), particularly at lower dose (0.5 and 0.25 mg/kg, i.p.). Pergolide, but not l-DOPA, reversed lesion-induced up-regulation of preproenkephalin and did not up-regulate preprodynorphine or DA D3 receptor in the lesioned hemisphere. Pergolide was as effective as l-DOPA in reversing the lesion-induced elevation of ERK2 phosphorylation in response to acute apomorphine administration (0.05 mg/kg, s.c.). Chronic l-DOPA significantly elevated the level of Akt phosphorylation at both Thr(308) and Ser(473) and concentration of phosphorylated GSK3alpha, whereas pergolide suppressed the lesion- and/or challenge-induced supersensitive Akt responses. The data indicate that l-DOPA, unlike pergolide, exacerbates imbalances in the Akt pathway caused by the loss of DA. The results support the hypothesis that the Akt pathway is involved in long-term actions of l-DOPA and may be linked to l-DOPA-induced dyskinesia. 相似文献
110.