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Inorganic dielectric films have attracted extensive attention in the field of microelectronic and electrical devices because of their wide operating temperature range, small size, and easy integration. Here, we designed and prepared eco-friendly (1-x)Bi0.45Na0.45Ba0.1TiO3-xBi(Mg1/3Nb2/3)O3 multifunctional ferroelectric thin films for energy storage and photovoltaic. The results show that Bi(Mg1/3Nb2/3)O3 can effectively improve the energy storage performance. At x = 0.05, the energy storage density and efficiency are as high as 73.1 J/cm3 and 86.2%, respectively, and can operate stably in a wide temperature range. The breakdown field strength of the thin films increased significantly, and the analysis showed that the addition of Bi(Mg1/3Nb2/3)O3 caused a change in the internal conduction mechanism. At the same time, the generation of polar nanoregions increases the relaxation characteristics, thus improving the energy storage properties. In addition, the thin film material also has excellent ferroelectric photovoltaic properties. This work represents a new design paradigm that can serve as an effective strategy for developing advanced multi-functional materials.

ABSTRACT: High broodiness in Muscovy ducks impedes animal husbandry growth. The interaction between endocrine hormones and gut microbiota has been proven to play a crucial role in reproductive performance, and whether it can regulate the broody behavior of Muscovy ducks requires further research. Nine laying ducks (Laying group) and nine broody ducks (Broodiness group) were selected. Corresponding serum, ileum, and cecum chyme were collected for further research. The results showed that, compared to the laying group, the serum concentration of prolactin decreased, while the levels of Mullerian inhibiting substance, follicle-stimulating hormone, and follistatin increased in the broodiness group (P < 0.05). 16S rDNA sequencing showed that, the broodiness group exhibited lower abundance levels of Rothia, Streptococcus, and Lactobacillus, whereas the abundance of Turicibacter, Aliicoccus, and Facklamia was higher in the ileum compared to the laying group (P < 0.05). In the cecum, the broodiness group exhibits a significant reduction in the abundance of Butyricicoccus and unclassified_f_Rikenellaceae, while the abundance of Christensenellaceae_R-7_group, Ruminococcus_torques_group, Parabacteroides, norank_f_Oscillospiraceae, Cloacibacillus, Sellimonas, Shuttleworthia, norank_f_UCG-010, unclassified_f_Lachnospiraceae, Oscillospira, Synergistes, Family_XIII_AD3011_group and Eubacterium_nodatum_group is higher compared to the laying group. A Spearman correlation analysis reveals that both in the ileum and cecum, serum hormones exhibit significant correlations with the top 20 abundant intestinal microbial genera. Among these, serum follistatin has most entries of significant correlations with the detected microbial genera (P < 0.05). In conclusion, the broody behavior of Muscovy ducks can be modulated by the interaction between hormones and gut microbiota. Notably, the relationship between Follistatin and the composition of gut microbiota, specifically Firmicutes, is the most prominent.

Abstract Small molecules with conformationally rigid, three-dimensional geometry are highly desirable in drug development, toward which a direct, simple-to-complexity synthetic logic is still of considerable challenges. Here, we report intermolecular aza-[2 + 2] photocycloaddition (the aza-Paternò–Büchi reaction) of indole that facilely assembles planar building blocks into ladder-shape azetidine-fused indoline pentacycles with contiguous quaternary carbons, divergent head-to-head/head-to-tail regioselectivity, and absolute exo stereoselectivity. These products exhibit marked three-dimensionality, many of which possess 3D score values distributed in the highest 0.5% region with reference to structures from DrugBank database. Mechanistic studies elucidated the origin of the observed regio- and stereoselectivities, which arise from distortion-controlled C-N coupling scenarios. This study expands the synthetic repertoire of energy transfer catalysis for accessing structurally intriguing architectures with high molecular complexity and underexplored topological chemical space.

Abstract Biomimetic materials are able to mimic the structure and functional properties of native tissues especially natural oral tissues. They have attracted growing attention for their potential to achieve configurable and functional reconstruction in oral medicine. Though tremendous progress has been made regarding biomimetic materials, significant challenges still remain in terms of controversy on the mechanism of tooth tissue regeneration, lack of options for manufacturing such materials and insufficiency of in vivo experimental tests in related fields. In this review, the biomimetic materials used in oral medicine are summarized systematically, including tooth defect, tooth loss, periodontal diseases and maxillofacial bone defect. Various theoretical foundations of biomimetic materials research are reviewed, introducing the current and pertinent results. The benefits and limitations of these materials are summed up at the same time. Finally, challenges and potential of this field are discussed. This review provides the framework and support for further research in addition to giving a generally novel and fundamental basis for the utilization of biomimetic materials in the future.

Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success, and what is the genetic basis underlying a personality trait—remain unresolved. We addressed these two questions in three shrub-nesting birds, the Azure-winged Magpie (Cyanopica cyanus, AM), White-collared Blackbird (Turdus albocinctus, WB), and Brown-cheeked Laughingthrush (Trochalopteron henrici, BL). The personality type of an individual was first identified according to its response to a territorial intruder. Then, we compared the fleeing distance, breeding parameters, and differential expressed genes (DEGs) in the brain transcriptome between bold and shy breeders. In the three species, bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders. The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL. The three species shared one DEG, crabp1, which was up-regulated in bold relative to in shy individuals. By regulating the expression of corticotropin-releasing hormone, higher crabp1 gene expression can decrease cellular response to retinoic acid. Therefore, bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts. Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not. Although a personality trait may have the same genetic basis across species, its correlation with reproductive success depends largely on the life history style of a species.

Abstract Objectives To explore an optimal model to predict the response of patients with axillary lymph node (ALN) positive breast cancer to neoadjuvant chemotherapy (NAC) with machine learning using clinical and ultrasound-based radiomic features. Methods In this study, 1014 patients with ALN-positive breast cancer confirmed by histological examination and received preoperative NAC in the Affiliated Hospital of Qingdao University (QUH) and Qingdao Municipal Hospital (QMH) were included. Finally, 444 participants from QUH were divided into the training cohort (n = 310) and validation cohort (n = 134) based on the date of ultrasound examination. 81 participants from QMH were used to evaluate the external generalizability of our prediction models. A total of 1032 radiomic features of each ALN ultrasound image were extracted and used to establish the prediction models. The clinical model, radiomics model, and radiomics nomogram with clinical factors (RNWCF) were built. The performance of the models was assessed with respect to discrimination and clinical usefulness. Results Although the radiomics model did not show better predictive efficacy than the clinical model, the RNWCF showed favorable predictive efficacy in the training cohort (AUC, 0.855; 95% CI 0.817–0.893), the validation cohort (AUC, 0.882; 95% CI 0.834–0.928), and the external test cohort (AUC, 0.858; 95% CI 0.782–0.921) compared with the clinical factor model and radiomics model. Conclusions The RNWCF, a noninvasive, preoperative prediction tool that incorporates a combination of clinical and radiomics features, showed favorable predictive efficacy for the response of node-positive breast cancer to NAC. Therefore, the RNWCF could serve as a potential noninvasive approach to assist personalized treatment strategies, guide ALN management, avoiding unnecessary ALND.

Bergapten, a furanocoumarin naturally occurring in bergamot essential oil, has been demonstrated to have the potential to alleviate osteoarthritis-related symptoms via its anti-inflammatory activity. Although its systemic bioavailability is limited, its precise mechanisms of action and effects on temporomandibular joint osteoarthritis (TMJOA) and its relationship with the intestinal flora remain unclear. Here, we explored the anti-TMJOA effect of BGT combined with the interleukin-1β-induced inflammatory response of chondrocytes in a monosodium iodoacetate (MIA)-induced TMJOA rat model. It was confirmed that BGT effectively reduced proinflammatory mediators and increased type II collagen, bone volume, and trabecular number of condyles in TMJOA rats. Importantly, the oral administration of BGT altered the intestinal flora of rats by increasing the relative abundances of nine prebiotic species and decreasing the relative abundance of one potential species. In addition, BGT considerably reduced reactive oxygen species (ROS) levels by suppressing glutathione, oxidized glutathione, and superoxide dismutase in the serum and malondialdehyde in urine. These results suggest that BGT exerts a chondroprotective effect, most likely by improving the intestinal flora and reducing ROS production associated with TMJOA in rats. This finding indicates a novel beneficial effect of BGT on the prevention and treatment of TMJOA.

Abstract Background Desensitization of G protein–coupled receptors (GPCRs) refers to a rapid attenuation of responsiveness that occurs with repeated or continuous exposure to agonists. GRK-mediated phosphorylation and subsequent binding with arrestins in the activated receptor cytoplasmic cavity in competition with G proteins has been suggested as the conventional mechanism of desensitization. Along with widely accepted conventional mechanism of desensitization, studies of various GPCRs including dopamine D2-like receptors (D2R, D3R, D4R) have suggested the existence of another desensitization mechanism. In this study, loss-of-function approaches and D2-like receptor mutants that display different desensitization properties were used to elucidate the molecular mechanisms responsible for desensitization. Results Desensitization development entailed the signaling cascade composed of Src, PDK1, and Akt, the latter of which in turn interacted with USP33, an arrestin deubiquitinase, to promote arrestin deubiquitination. The deubiquitinated arrestin subsequently formed a complex with Gβγ and translocated to the nucleus via an importin complex, wherein it sequestered Gβγ from the receptor and Gα, thereby attenuating receptor signaling. As in D2-like receptors, both USP33 and importin β1 were involved in the desensitization of the β2 adrenoceptor. Conclusions In addition to the conventional mechanism of desensitization, which occurs on the plasma membrane and in the cytosol, this study provides a new insight that another desensitization pathway in which nuclear trafficking plays a critical role is operating. It is plausible that multiple, complementary desensitization measures are in place to properly induce desensitization depending on receptor characteristics or the surrounding environment. Video Abstract

The immense potential of flexible energy storage materials applied in wearable electronic devices has stimulated a lot of science researches on manufacturing technology and performance optimization. Herein, an all-inorganic flexible ferroelectric film with multilayer heterostructure is prepared based on Mn doped Bi0.5Na0.5TiO3BiNi0.5Zr0.5O3 (Mn:BNT-BNZ) and Bi0.5Na0.5TiO3BiZn0.5Zr0.5O3 (BNT-BZZ) relaxor ferroelectrics. A win-win situation of breakdown strength and polarization is achieved in the Mn:BNT-BNZ/BNT-BZZ multilayer film with the stacking period N = 3, of which energy density and efficiency reach 80.4 J/cm3 and 62.0% respectively. It is proposed that the excellent energy storage performances are attributed to the synergistic effect of the electric field amplification effect, interface blocking effect and the polarization coupling effect based on the multilayer heterostructure. Moreover, the flexible ferroelectric film exhibits outstanding temperature (25–205 °C), frequency (0.5–5 kHz) stability and antifatigue property (1 × 108 cycles), and can well maintain stable performance at different tensile/compressive bending radii (10–5 mm) and even after 104 bending cycles with a fixed bending radius of 3 mm. This work opens up a promising route to the development of flexible energy storage materials.

Ferroelectric materials are considered to be the most competitive energy storage materials for applications in pulsed power electronics due to excellent charge–discharge properties. However, the low energy storage density is the primary problem limiting their practical application. In this study, (1[Formula: see text])Na[Formula: see text]Bi[Formula: see text]TiO3–[Formula: see text]Sr[Formula: see text]La[Formula: see text]TiO3[(1[Formula: see text])NBT–[Formula: see text]SLT] ferroelectric ceramics are found to exhibit excellent energy storage performances through a synergistic strategy. As the SLT concentration increases, the relaxation characteristic increases significantly and the breakdown strength increases dramatically from 150 kV/cm to 220 kV/cm. The recoverable energy storage density of the 0.55NBT–0.45SLT ceramic is 2.86 J/cm3 with an energy storage efficiency of 88% under an electric field of 220 kV/cm. Furthermore, the ceramic with [Formula: see text] = 0.45 mol exhibited excellent energy storage stability in the ranges of 20–180[Formula: see text]C (temperature) and 1–125 Hz (frequency). These excellent properties demonstrate the potential of (1[Formula: see text])NBT–[Formula: see text]SLT ceramics when used as dielectric capacitors in pulsed power systems.

It is a two-way interaction between algae bloom events and nutrient cycles in aquatic environments. In Meiliang bay of Taihu Lake, phosphorus (P) forms in the water, sediment and pore water, and bacterial community structures in the sediment were investigated in June 2021 (the algae bloom period) and December 2021 (the algae collapse period). The aim of this study is to clarify the periodic variations of P migration and transformation driven by algae bloom and collapse. Results showed that concentrations of total P and total particulate P in the water during the algae bloom period (.13–.25 mg/L) were much higher than those during the algae collapse period (0–.13 mg/L), which was mainly caused by the uptake of phosphate (PO43-) by algae in the surface water. Compared with the algae bloom period, there were higher concentrations of organic P (OP), iron-bound P (FeP) and inorganic P in the sediments during the algae collapse period. The propositions of OP and FeP in total P in the sediments increased from 19% to 17% during the algae bloom period to 27% and 33% during the algae collapse period. These suggest the cumulative trend of OP and FeP in the sediments during the algae collapse period, and FeP might be formed through the processes of OP mineralization and P adsorption by iron oxides/hydroxides in the sediments. Different routes of sediment P regeneration existed over the two periods. During the algae bloom period, the similar vertical variations of labile PO43- and labile Fe2+ in the sediments provided in situ, high-resolution evidence for FeP reductive dissolution driven by FRBs activities. During the algae collapse period, OP mineralization driven by organic P-solubilizing bacteria activities and accelerated by the sulfate reduction process was confirmed by the similar vertical variations of labile PO43- and labile S2- in the sediments. Therefore, treatment approaches and management practices should consider the periodic variations of internal P cycles in aquatic environments during the algae bloom and algae collapse periods to avoid inefficient treatments of lake eutrophication and algae bloom.

Abnormal communication between endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) promotes vascular diseases, including atherogenesis. ETS variant transcription factor 2 (ETV2) plays a substantial role in pathological angiogenesis and the reprogramming of ECs; however, the role of ETV2 in the communication between ECs and VSMCs has not been revealed. To investigate the interactive role of ETV2 in the EC to VSMC phenotype, we first showed that treatment with a conditioned medium from ETV2-overexpressed ECs (Ad-ETV2 CM) significantly increased VSMC migration. The cytokine array showed altered levels of several cytokines in Ad-ETV2 CM compared with those in normal CM. We found that C-X-C motif chemokine 5 (CXCL5) promoted VSMC migration using the Boyden chamber and wound healing assays. In addition, an inhibitor of C-X-C motif chemokine receptor 2 (CXCR2) (the receptor for CXCL5) significantly inhibited this process. Gelatin zymography showed that the activities of matrix metalloproteinase (MMP)-2 and MMP-9 increased in the media of VSMCs treated with Ad-ETV2 CM. Western blotting revealed a positive correlation between Akt/p38/c-Jun phosphorylation and CXCL5 concentration. The inhibition of Akt and p38-c-Jun effectively blocked CXCL5-induced VSMC migration. In conclusion, CXCL5 from ECs induced by ETV2 promotes VSMC migration via MMP upregulation and the activation of Akt and p38/c-Jun.

With the continuous development of coating technology and environmental protection concepts, coating has become an indispensable item in the field of architecture and industry. Styrene acrylic emulsion as a new type of waterborne paint has attracted much attention since its emergence. Its functional modification is the focus of research, but the research results have not been ideal. To further improve the performance of styrene acrylic emulsion, nano-ZnO composite polystyrene emulsion was synthesized by emulsion polymerization, and its properties were analyzed. Aiming at the problem that nanopigments are prone to agglomeration, corresponding solutions are proposed, and the stability of nano-coatings is preliminarily studied. The inherent culture and essence of traditional culture and art is the wealth of realizing the unique nationalization and internationalization of design works. There is a lot of artistic quintessence in traditional Chinese painting art that can be used for reference to visual communication design. Through in-depth understanding and learning of Chinese painting theory and techniques, designers’ aesthetic abilities and innovation abilities can be qualitatively improved. First of all, the emulsion polymerization was carried out by semicontinuous method. The composite polystyrene emulsion containing different content of nano-ZnO was successfully prepared, which was recorded as N, Z, Z15, Z25, and Z35, respectively. The properties of the emulsion were determined, and the solid content, monomer conversion, viscosity, water absorption, and bacteriostatic effect of the emulsion were determined. The experimental results show that the solid content of emulsion Z15 (nano-ZnO content is 15%) reaches the highest value of 43.5%. The content of monomer in the emulsion affects the solid content, but the higher the monomer content, the better the solid content. The highest monomer conversion of Z15 was 86.4% at 80°C. The monomer conversion increased with the increase of polymerization temperature and tended to be stable after reaching the highest value. In the absence of nano-ZnO, the viscosity of the emulsion is the highest, and the viscosity of the emulsion decreases with the increase of the content of nano-ZnO monomer. Z35 (when the content of nano-ZnO is 35%) is the highest, which is 18.91%. The water absorption increases with the increase of nano-ZnO content. The content of nano-ZnO in the emulsion increased, the MIC value became smaller, and the bacteriostatic effect became better and better. This indicates that nano-ZnO composite polystyrene emulsion has good monomer conversion, super water resistance, and bacteriostatic effect, but its viscosity is relatively poor.

Trichoderma reesei is widely applied as the major industrial fungus for the production of cellulases used for the conversion of lignocellulosic biomass to biofuels and other biobased products. The protein secretion pathway is vital for cellulase secretion, but few reports are related to the role of the vacuole in cellulase production. Here, we identified a novel vacuolar serine protease gene spt1 and investigated the ability of T. reesei to secrete cellulases by disrupting, complementing and overexpressing the spt1 gene. Amino acid sequence analysis of the Spt1 protein showed that it belongs to the subtilisin S8 family and has the conserved catalytic triples (Asp, His, Ser) of the serine protease. The deletion of spt1 did not lead to a decrease in extracellular protease activity, and the observation of mycelia with the Spt1–eGFP fusion expression and the vacuolar membrane dye FM4-64 staining confirmed that Spt1 was an intracellular protease located in the vacuoles of T. reesei. However, the spt1 gene deletion significantly reduced spore production and cellulase secretion, while the spt1 complementation recovered these traits to those of the parental strain. When spt1 was overexpressed by using its native promoter and introducing multiple copies, the cellulase secretion was improved. Furthermore, a strong promoter, Pcdna1, was used to drive the spt1 overexpression, and it was found that the cellulase production was significantly enhanced. Specifically, the filter paper activity of the spt1 overexpression strain SOD-2 reached 1.36 U/mL, which was 1.72 times higher than that of the parental strain. These findings demonstrated that the spt1 gene can be a powerful target for increasing cellulase production in T. reesei, which suggests a possible important role of the vacuole in the cellulase secretion pathway and provides new clues for improving strains for efficient cellulase production.

We prepared a dense AgNbO3 ceramic using a conventional solid-state reaction method. The phase structure, electrical properties and electrocaloric effect (ECE) were systematically investigated. Large negative and positive ECEs (−4.38 °C at 65 °C and 2.3 °C at 210 °C) under an external electric field of 180 kV·cm−1 were obtained in the eco-friendly AgNbO3 antiferroelectric (AFE) ceramic due to affluent phase transition and a high electric field. The large positive and negative ECEs originated from the phase transition between ferrielectric (FIE) phases (the orthorhombic space group (Pmc21) and AFE phases (Pbcm) tuned by an applied external field. Additionally, a probable mechanistic model was proposed to illustrate the generation of positive and negative ECEs. This study may provide guidelines for the design of high-efficiency solid-state cooling devices.

Algae bloom event, an extreme ecological imbalance that the water environment experiences, changes the phosphorus (P) cycle in the aquatic environment, which makes the lake maintain a long-term eutrophication and frequent algae bloom state. This study compared P form characteristics and bacteria community structures in the aquatic environment of the cyanobacteria area and non-cyanobacteria area of Taihu Lake, aiming to clear the new P cycle pattern disturbed by algae bloom and decomposition processes. Compared with P forms in mediums of the middle of the lake and the east of the lake, there were higher concentration levels of total particulate P (TPP) in water, organic P (OP) in suspended particles, iron bound P (FeP) in sediments and phosphate (PO43−) in the pore water of Meiliang Bay, the cyanobacteria area. OP form was the dominant P fraction in suspended particles that occupied 69% in particulate total P, but OP proportion in sediments decreased to 26% of sediment total P, which indicated the strong occurrence of OP mineralization in sediments. The higher concentration and proportion of FeP in sediments of Meiliang Bay suggested the intensified effects of algae bloom and decomposition on sediment FeP accumulation. In Meiliang Bay, the positive correlation between Fe2+ and PO43− in pore water and the higher diffusion fluxes of Fe2+, PO43− from pore water to overlying water (0.45, 0.65 mg/m2·d) than that in the other lake areas also suggested the intensified effects of algae bloom and decomposition on FeP reductive dissolution in sediments accompanying sediment P remobilization. Moreover, there were higher concentrations of labile sulfide and high relative abundances of iron reducing bacteria (FRBs), sulfate reducing bacteria (SRBs) in sediments of Meiliang Bay. Results suggested that algae bloom event changed the natural P cycle in aquatic environment through intensifying the pathways of sediment OP mineralization, FeP accumulation and FeP reductive dissolution, which were mainly driven by the coupled factors of anoxic sediment condition, SRBs and FRBs activities. In addition, PO43− diffusion from pore water to overlying water in the east of the lake may be prevented for its much higher Fe/P ratio (8.06) and Fe2+ concentrations in pore water, which may form a P-adsorbing barrier of iron oxides in the interface between pore water and overlying water. This study enhances the understanding of the vicious P cycle pattern in the aquatic environment driven by algae bloom and decomposition, which should be considered when conducting eutrophication prevention and control measures on lakes.

Energy-storage capacitors based on relaxation ferroelectric ceramics have attracted a lot of interest in pulse power devices. How to improve the energy density by designing the structure of ceramics through simple approaches is still a challenge. Herein, enhanced energy-storage performances are achieved in relaxation ferroelectric 0.9 (0.94Na0.5Bi0.5TiO3-0.06BaTiO3)-0.1NaNbO3 (NBT-BT-NN) ceramics by tuning sintering temperature. The original observation based on Kelvin probe force microscopy (KPFM) presented that the sintering temperature has a key effect on the electrical homogeneousness of the ceramics. It is found that a high electrical homogeneousness can induce quick and active domain switching due to the weakening of the constraint from built-in fields, resulting in a big polarization difference. This work provides a feasible strategy to design high-performance energy-storage ceramic capacitors.

Hashimoto’s encephalopathy (HE) is a rare neuropsychiatric syndrome characterized by elevated levels of anti-thyroid antibodies. Diverse manifestations make timely diagnosis of HE difficult. Herein, we report a case of HE, in which the clinical symptoms and laboratory test results mimicked viral encephalitis. A 59-year-old male patient, who presented with a fever, headache, slow and unclear speech, sentence confusion, elevated levels of anti-thyroid antibodies in the serum, an increased white blood cell count, and positivity for anti-thyroid antibodies in the CSF, was finally diagnosed with HE and responded well to a small dose of methylprednisolone. This report helps bring the attention of clinicians to the fact that HE should be considered when cases of unexplained encephalopathy are encountered.

The filamentous fungus Trichoderma reesei is one of the most studied cellulolytic organisms and the major producer of cellulases for industrial applications. However, undesired degradation of cellulases often happens in culture filtrates and commercial enzyme preparations. Even studies have been reported about describing proteolytic degradation of heterologous proteins in T. reesei, there are few systematic explorations concerning the extracellular proteases responsible for degradation of cellulases. In this study, the cellulase activity was observed to rapidly decrease at late cultivation stages using corn steep liquor (CSL) as the nitrogen source in T. reesei. It was discovered that this decrease may be caused by proteases. To identify the proteases, comparative secretomics was performed to analyze the concomitant proteases during the cellulase production. 12 candidate proteases from the secretome of T. reesei were identified and their encoding genes were individually deleted via homologous recombination. Furthermore, three target proteases (tre81070, tre120998, and tre123234) were simultaneously deleted by one-step genetic transformation. The triple deletion strain ΔP70 showed a 78% decrease in protease activity and a six-fold increase in cellulase activity at late fermentation stages. These results demonstrated the feasibility of improvement of cellulase production by genetically disrupting the potential protease genes to construct the T. reesei strains with low extracellular protease secretion. This dataset also provides an efficient approach for strain improvement by precise genetic engineering combined with “omics” strategy for high-production of industrial enzymes to reduce the cost of lignocellulose bioconversion.

Abstract Background Trichoderma reesei is one of the most important fungi utilized for cellulase production. However, its cellulase system has been proven to be present in suboptimal ratio for deconstruction of lignocellulosic substrates. Although previous enzymatic optimization studies have acquired different types of in vitro synthetic mixtures for efficient lignocellulose hydrolysis, production of in vivo optimized cellulase mixtures by industrial strains remains one of the obstacles to reduce enzyme cost in the biofuels production from lignocellulosic biomass. Results In this study, we used a systematic genetic strategy based on the pyrG marker to overexpress the major cellulase components in a hypercellulolytic T. reesei strain and produce the highly efficient cellulase mixture for saccharification of corncob residues. We found that overexpression of CBH2 exhibited a 32-fold increase in the transcription level and a comparable protein level to CBH1, the most abundant secreted protein in T. reesei, but did not contribute much to the cellulolytic ability. However, when EG2 was overexpressed with a 46-fold increase in the transcription level and a comparable protein level to CBH2, the engineered strain QPE36 showed a 1.5-fold enhancement in the total cellulase activity (up to 5.8 U/mL FPA) and a significant promotion of saccharification efficiency towards differently pretreated corncob residues. To assist the following genetic manipulations, the marker pyrG was successfully excised by homologous recombination based on resistance to 5-FOA. Furthermore, BGL1 was overexpressed in the EG2 overexpression strain QE51 (pyrG-excised) and a 11.6-fold increase in BGL activity was obtained. The EG2–BGL1 double overexpression strain QEB4 displayed a remarkable enhancement of cellulolytic ability on pretreated corncob residues. Especially, a nearly complete cellulose conversion (94.2%) was found for the delignified corncob residues after 48 h enzymatic saccharification. Conclusions These results demonstrate that genetically exploiting the potentials of T. reesei endogenous cellulases to produce highly efficient cellulase mixtures is a powerful strategy to promote the saccharification efficiency, which will eventually facilitate cost reduction for lignocellulose-based biofuels.

Avian influenza A viruses are serious veterinary pathogens that normally circulate among avian populations, causing substantial economic impacts. Some strains of avian influenza A viruses, such as H5N1, H9N2, and recently reported H7N9, have been occasionally found to adapt to humans from other species. In order to replicate efficiently in the new host, influenza viruses have to interact with a variety of host factors. In the present study, H7N9 nucleoprotein was transfected into human HEK293T cells, followed by immunoprecipitated and analyzed by proteomics approaches. A series of host proteins co-immunoprecipitated were identified with high confidence, some of which were found to be acetylated at their lysine residues. Bioinformatics analysis revealed that spliceosome might be the most relevant pathway involved in host response to nucleoprotein expression, increasing our emerging knowledge of host proteins that might be involved in influenza virus replication activities.

In the present study, hematopoietic progenitor kinase 1 (HPK1)-interacting protein of 55 kDa (HIP-55) protein was over-expressed in HEK293 cells, which was genetically attached with 6x His tag. The protein was purified by nickel-charged resin and was then subjected to tryptic digestion. The phosphorylated peptides within the HIP-55 protein were enriched by TiO2 affinity chromatography, followed by mass spectrometry analysis. Fourteen phosphorylation sites along the primary structure of HIP-55 protein were identified, most of which had not been previously reported. Our results indicate that bio-mass spectrometry coupled with manual interpretation can be used to successfully identify the phosphorylation modification in HIP-55 protein in HEK293 cells.

Amino acid substitutions in influenza A virus are the main reasons for both antigenic shift and virulence change, which result from non-synonymous mutations in the viral genome. Nucleocapsid protein (NP), one of the major structural proteins of influenza virus, is responsible for regulation of viral RNA synthesis and replication. In this report we used LC-MS/MS to analyze tryptic digestion of nucleocapsid protein of influenza virus (A/Puerto Rico/8/1934 H1N1), which was isolated and purified by SDS poly-acrylamide gel electrophoresis. Thus, LC-MS/MS analyses, coupled with manual de novo sequencing, allowed the determination of three substituted amino acid residues R452K, T423A and N430T in two tryptic peptides. The obtained results provided experimental evidence that amino acid substitutions resulted from non-synonymous gene mutations could be directly characterized by mass spectrometry in proteins of RNA viruses such as influenza A virus.

Trichoderma reesei is a biotechnologically important filamentous fungus with the remarkable ability to secrete large amounts of enzymes, whose production is strongly affected by both the carbon and nitrogen sources. While the carbon metabolism regulators are extensively studied, the regulation of enzyme production by the nitrogen metabolism regulators is still poorly understood. In this study, the GATA transcription factor Are1, which is an orthologue of the Aspergillus global nitrogen regulator AREA, was identified and characterized for its functions in regulation of both protease and cellulase production in T. reesei. Deletion of the are1 gene abolished the capability to secrete proteases, and complementation of the are1 gene rescued the ability to produce proteases. Quantitative RT-PCR analysis revealed that the transcripts of protease genes apw1 and apw2 were also significantly reduced in the Δare1 strain when grown in the medium with peptone as the nitrogen source. In addition, deletion of are1 resulted in decreased cellulase production in the presence of (NH4)2SO4. Consistent with the reduction of cellulase production, the transcription levels of the major cellulase genes, including cbh1, cbh2, egl1, and egl2, were dramatically decreased in Δare1. Sequence analysis showed that all promoter regions of the tested protease and cellulase genes contain the consensus GATA elements. However, the expression levels of the major cellulase transcription activator Xyr1 and the repressor Cre1 had no significant difference between Δare1 and the parental strain QM9414, indicating that the regulatory mechanism deserves further investigation. Taken together, these results demonstrate the important role of Are1 in the regulation of protease and cellulase production in T. reesei, although these processes depend on the kind of nitrogen sources. The findings in this study contribute to the understanding of the regulation network of carbon and nitrogen sources in filamentous fungi.