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Studying plant early immunity, such as the unique immune mechanisms against pathogens, is an important field of research. Tomato wilt resulting from the infection by Fusarium oxysporum f. sp. lycopersici (Fol) is an important soil-borne vascular disease. In this study, we challenged tomato plants with Fol for a time-course RNA sequencing (RNA-seq) analysis. The result indicated that phenylpropanoid and flavonoid pathway genes were significantly enriched during the early invasion stage. Further study revealed that the flavonoids galangin and quercetin could effectively inhibit Fol growth and enhance wilt resistance in tomato. Moreover, the genes involved in plant-pathogen interactions, the MAPK signaling pathway, and plant hormone signal transduction were significantly enriched. These genes were also involved in plant pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) signaling pathways. Strikingly, the transcription levels of pathogen-related protein 1 (SlPR1) were dramatically increased at 2 days post Fol inoculation, implying that SlPR1 is important in early immunity in tomato. SlPR1 does not have direct antifungal activity. Instead, its C-terminal peptide CAPE1 could activate root defense responses, such as the reactive oxygen species (ROS) burst, salicylic acid (SA)/jasmonic acid (JA) production, and defense-related gene expression, which collectively increased tomato resistance to Fol infection. In addition, CAPE1 could induce systemic acquired resistance (SAR). Application of CAPE1 onto tomato leaves induced local resistance to the pathogen Botrytis cinerea and systemic resistance to Fol infection. These results advanced our understanding for the early immunity against Fol in tomato and provide potential strategy for tomato disease control.

We demonstrate the propagation dynamics of optical breathers in nonlinear media with a spatial nonlocality, which is governed by the nonlocal nonlinear Schrodinger equation, by employing the variational approach. Taking a tripole breather as an example, the approximate analytical solution is obtained and the physical propagation properties, such as the evolution of the critical power, the spot size, the wavefront curvature, and the intensity distribution of the breather, have been discussed in detail. The physical reasons for the evolution of the tripole breathers are analyzed by borrowing the ideas from Newtonian mechanics. It is found that the analytical results obtained by the variational approach agree well with the numerical results of the nonlocal Schrodinger equation for the strong nonlocal case, especially when the incident power approaches the critical power.

Novel Sb3+-doped Ag/AgCl photocatalysts containing different fractions of Sb3+ were synthesized by a simple coprecipitation method and systematically characterized by many techniques. The activity was maximized at the dosage of 2 wt% Sb3+ in methyl orange (MO) photodegradation experiments, and was reserved after three cycles. The photocatalytic activity was decided by the effective separation and low recombination rate of photogenerated electron–hole pairs. The high activities theoretically contributed to the Sb3+-induced formation of chloride dangling bonds and vacancies. The activity of Sb3+-doped Ag/AgCl (2 wt%) maximized to 98% after 14 min, which was much higher than the 50% of pure Ag/AgCl. Electron spin resonance and photoluminescence spectrum showed ·OH was the main active species during the MO oxidation over Sb3+-doped Ag/AgCl.

Pure WO3 powder was prepared from a simple method and applied into sonocatalytic degradation of rhodamine B (RhB), the model compound. The structure and properties of samples were characterized by X-ray diffractometry (XRD), transmission electron microscopy (TEM), ultraviolet–visible (UV–vis) absorption spectroscopy, and photoluminescence (PL) spectroscopy. We studied the effects of WO3 on the sonocatalytic degradation of RhB and the operational parameters such as catalyst dosage and RhB concentration. The experimental results showed that the best sonocatalytic degradation ratio (59.39%) of organic dyes could be obtained when the optimal conditions of 10.00-mg/L initial concentration, 3.00-g/L prepared WO3 powder added amount, 99-W ultrasound output power, and 270-min ultrasonic irradiation were adopted. Under ultrasonic conditions, the degradation rate after addition of WO3 reached the highest activity of 57.9%, and about three times the rate of degradation was not added. Abundant ·OH was induced by WO3 powder under ultrasonic irradiation, which may be the main contributor to the high sonodegradation rate.

Interleukin-1β (IL-1β) plays a crucial role in mediating inflammation and innate immunity response in the central nervous system. Death-associated protein kinase 1 (DAPK1) was shown to be involved in several cellular processes. Here, we investigated the effects of DAPK1 on IL-1β production in microglial cells. We used a combination of in vitro (Bv2 microglial cell cultures) and in vivo (mice injected with amyloid-β (Aβ)) techniques to address the role of caspase-1 activation in release of IL-1β. DAPK1 involvement was postulated through genetic approaches and pharmacological blockade of this enzyme. We found that Aβ25–35 stimulation induced IL-1β production and caspase-1 activation in LPS-primed Bv2 cells and mice. DAPK1 knockdown and catalytic activity inhibition reduced IL-1β maturation and caspase-1 activation, nevertheless, DAPK1 overexpression attenuated these effects. Aβ25–35-induced lysosomal cathepsin B leakage was required for DAPK1 activation. Furthermore, repeated DAPK1 inhibitor treatment ameliorated the memory impairment in Aβ25–35-injected mice. Taken together, our findings suggest that DAPK1 facilitates Aβ25–35-induced IL-1β production through regulating caspase-1 activation in microglial cells.

BoMF25 acts on pollen wall. Polygalacturonase (PG) is a pectin-digesting enzyme involved in numerous plant developmental processes and is described to be of critical importance for pollen wall development. In the present study, a PG gene, BoMF25, was isolated from Brassica oleracea. BoMF25 is the homologous gene of At4g35670, a PG gene in Arabidopsis thaliana with a high expression level at the tricellular pollen stage. Collinear analysis revealed that the orthologous gene of BoMF25 in Brassica campestris (syn. B. rapa) genome was probably lost because of genome deletion and reshuffling. Sequence analysis indicated that BoMF25 contained four classical conserved domains (I, II, III, and IV) of PG protein. Homology and phylogenetic analyses showed that BoMF25 was clustered in Clade F. The putative promoter sequence, containing classical cis-acting elements and pollen-specific motifs, could drive green fluorescence protein expression in onion epidermal cells. Quantitative RT-PCR analysis suggested that BoMF25 was mainly expressed in the anther at the late stage of pollen development. In situ hybridization analysis also indicated that the strong and specific expression signal of BoMF25 existed in pollen grains at the mature pollen stage. Subcellular localization showed that the fluorescence signal was observed in the cell wall of onion epidermal cells, which suggested that BoMF25 may be a secreted protein localized in the pollen wall.

Background Protein lysine succinylation is an important post-translational modification and plays a critical regulatory role in almost every aspects of cell metabolism in both eukaryotes and prokaryotes. Common wheat is one of the major global cereal crops. However, to date, little is known about the functions of lysine succinylation in this plant. Here, we performed a global analysis of lysine succinylation in wheat and examined its overlap with lysine acetylation. Results In total, 330 lysine succinylated modification sites were identified in 173 proteins. Bioinformatics analysis showed that the modified proteins are distributed in multiple subcellular compartments and are involved in a wide variety of biological processes such as photosynthesis and the Calvin-Benson cycle, suggesting an important role for lysine succinylation in these processes. Five putative succinylation motifs were identified. A protein interaction network analysis revealed that diverse interactions are modulated by protein succinylation. Moreover, 21 succinyl-lysine sites were found to be acetylated at the same position, and 33 proteins were modified by both acetylation and succinylation, suggesting an extensive overlap between succinylation and acetylation in common wheat. Comparative analysis indicated that lysine succinylation is conserved between common wheat and Brachypodium distachyon. Conclusions These results suggest that lysine succinylation is involved in diverse biological processes, especially in photosynthesis and carbon fixation. This systematic analysis represents the first global analysis of lysine succinylation in common wheat and provides an important resource for exploring the physiological role of lysine succinylation in this cereal crop and likely in all plants. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3698-2) contains supplementary material, which is available to authorized users.

Recently, a serial of studies have demonstrated that lipid mediators derived from Omega-3 fatty acid docosahexaenoic acid have pro-resolving or anti-inflammatory effects in many inflammatory diseases. Here, we sought to evaluate whether Protectin DX (PDX, an isomer of Protecin D1), a newly identified lipid mediator, could protect mice against sepsis and explore the underling mechanism. Animal model of sepsis was established by cecum ligation and puncture (CLP). We found that PDX increased overall survival rate within eight days and attenuated multiple organ injury in septic mice. In addition, PDX reduced pro-inflammatory cytokines and bacterial load 24 h after CLP. Moreover, PDX promoted phagocytosis of peritoneal macrophages and increased the percentage of M2 macrophages in peritoneum of septic mice. In vitro, M2 macrophage markers (Arg1 and Ym1) and its transcriptional regulator (peroxisome proliferator-activated receptor-γ, PPAR-γ) were upregulated in Raw264.7 macrophages challenged with PDX. GW9662 (a PPAR-γ inhibitor) and PPAR-γ siRNA abrogated the induction of Arg1 and Ym1 by PDX in Raw264.7 cells. Taken together, our results suggest that PDX is able to promote M2 polarization, enhance phagocytosis activity of macrophage and accelerate resolution of inflammation, finally leading to increased survival rate of septic mice.

Lysine acetylation of proteins, a dynamic and reversible post-translational modification, plays a critical regulatory role in both eukaryotes and prokaryotes. Several researches have been carried out on acetylproteome in plants. However, until now, there have been no data on common wheat, the major cereal crop in the world. In this study, we performed a global acetylproteome analysis of common wheat variety (Triticum aestivum L.), Chinese Spring. In total, 416 lysine modification sites were identified on 277 proteins, which are involved in a wide variety of biological processes. Consistent with previous studies, a large proportion of the acetylated proteins are involved in metabolic process. Interestingly, according to the functional enrichment analysis, 26 acetylated proteins are involved in photosynthesis and Calvin cycle, suggesting an important role of lysine acetylation in these processes. Moreover, protein interaction network analysis reveals that diverse interactions are modulated by protein acetylation. These data represent the first report of acetylome in common wheat and serve as an important resource for exploring the physiological role of lysine acetylation in this organism and likely in all plants.

The constant modulus algorithm based on fractional lower-order statistics (FLOS_CMA) has been proven to be an effective blind equalization method under α-stable noise. But there have been little results in the literature about the performance of this algorithm. In this paper, the steady-state mean-square error (MSE) performance of the FLOS_CMA is studied, and the approximate analytical expressions for real- and complex-valued data under stationary and non-stationary environments are derived, respectively, based on the energy-preserving relation and a Taylor series expansion. Based on the derived expression, an estimate for the FLOS_CMA step-size interval to ensure its convergence and stability is obtained, when it is initialized sufficiently close to the zero-forcing solution. Finally, simulation studies are undertaken to support the analysis.

S–N-codoped TiO2 powders have been synthesized through a facile one-step sol–gel method by using tetrabutyltitanate and thiourea as precursors. The S–N-codoped TiO2 treated at 500 °C showed the highest photocatalytic activity for degrading methylene blue under visible light irradiation. XRD, XPS and UV–vis studies revealed that the high visible-light photocatalytic activity of the doped TiO2 may originate from the synergetic effect of sulfur and nitrogen codoping into TiO2.

Integrating 26 624 pairs of video frames, the authors have mapped the circular polarization in an active-region filament against the solar disk by using a traditional magnetograph working at the Hβ line. This filament, offset the disk center, appeared at the boundary of three decayed active regions. It was quiet and away from any strong enhanced network. The mapped circular polarization in the filament has an average polarization degree of 1.1×10−3 with a measurement precision of 4×10−4. The mapping of circular polarization in a filament may provide a supplementary diagnosis of the filament magnetic field, in addition to the mapping of linear polarization via the Hanle effect. However, the interpretation of the circular polarization requires treatment of the full quantum problem of Zeeman and non-Zeeman effects of Stokes line profiles.

By using multi-wavelength observations, we explored the atmospheric dynamics and the surface magnetic activity in NOAA 9026, which were associated with the initiation of a halo coronal mass ejection (CME) on 6 June, 2000. In an interval of less than two hours, two X-class X-ray flares took place successively, each along with one eruption of a filament. However, only the second X-class flare which is characterized by a rather large-scale (larger than a general active region in area) EUV dimming was associated with the CME initiation. It seems that a flare with an extensive dimming is more likely to be CME-associated. We focused our study on the daily evolution of the vector magnetic field in this region from 4 to 9 June and have found the following results. (1) The gradual squeeze and cancellation of the opposite polarity magnetic fields are the main patterns of magnetic evolution. Moreover, there is a spatial coincidence between the sites of magnetic flux cancellation and the locations of the early filament activation and the flare brightenings. (2) The current system increased in the first two days and began to decrease at least ten hours before the CME initiation. It underwent dramatic disruption from 6 to 7 June. (3) The transverse component of the the vector magnetic field appeared helical in configuration. It changed from compact to loose and dissipated from a small to a large area. Here we suggest that although the first filament eruption and first flare were not in step with the CME initiation, they seem to be a part of the entire process. The observed evolution of the magnetic field implies a continuous transport of magnetic energy and complexity from the lower atmosphere to the corona. Moreover, the slow magnetic reconnection in the lower atmosphere, manifested as magnetic flux cancellation, and the helicity re-distribution, appear to play a key role in the energy build-up process of the flares and the initiation of the halo CME.