Pro‐apoptotic Noxa is involved in ablative focal irradiation‐induced lung injury

Although lung injury including fibrosis is a well‐documented side effect of lung irradiation, the mechanisms underlying its pathology are poorly understood. X‐rays are known to cause apoptosis in the alveolar epithelial cells of irradiated lungs, which results in fibrosis due to the proliferation and differentiation of fibroblasts and the deposition of collagen. Apoptosis and BH3‐only pro‐apoptotic proteins have been implicated in the pathogenesis of pulmonary fibrosis. Recently, we have established a clinically analogous experimental model that reflects focal high‐dose irradiation of the ipsilateral lung. The goal of this study was to elucidate the mechanism underlying radiation‐induced lung injury based on this model. A radiation dose of 90 Gy was focally delivered to the left lung of C57BL/6 mice for 14 days. About 9 days after irradiation, the mice began to show increased levels of the pro‐apoptotic protein Noxa in the irradiated lung alongside increased apoptosis and fibrosis. Suppression of Noxa expression by small interfering RNA protected cells from radiation‐induced cell death and decreased expression of fibrogenic markers. Furthermore, we showed that reactive oxygen species participate in Noxa‐mediated, radiation‐induced cell death. Taken together, our results show that Noxa is involved in X‐ray‐induced lung injury.     

The adsorption of NO,NH<Subscript>3</Subscript>, N<Subscript>2</Subscript> on carbon surface: a density functional theory study

To explore the adsorption mechanism of NO, NH₃, N₂ on a carbon surface, and the effect of basic and acidic functional groups, density functional theory was employed to investigate the interactions between these molecules and carbon surfaces. Molecular electrostatic potential, Mulliken population analyses, reduced density gradient, and Mayer bond order analyses were used to clarify the adsorption mechanism. The results indicate that van der Waals interactions are responsible for N₂ physisorption, and N₂ is the least likely to adsorb on a carbon surface. Modification of carbon materials to decorate basic or acidic functional groups could enhance the NH₃ physisorption because of hydrogen bonding or electrostatic interactions, however, NO physisorption on a carbon surface is poor. Zig-zag sites are more reactive than armchair sites when these gas molecules absorb on the edge sites of carbon surface.

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Graphical abstract NH₃, N₂, NO adsortion on carbon surface

     

<Emphasis Type="Italic">ALDH2</Emphasis> genes are negatively correlated with natural deastringency in Chinese PCNA persimmon (<Emphasis Type="Italic">Diospyros kaki</Emphasis> Thunb.)

Chinese pollination-constant and non-astringent persimmon (C-PCNA) has important application values in the genetic improvement of PCNA for its trait of natural deastringency controlled by a single dominant gene. However, the key genes and the regulatory networks are still not fully understood. The process of C-PCNA natural deastringency may be associated with the acetaldehyde-mediated coagulation of soluble tannins, but the functions of ALDH2 genes related to the metabolism of acetaldehyde are not clear. In this work, three types of persimmon cultivars, ‘Eshi 1’ and ‘Luotian Tianshi’ (C-PCNA type), ‘Youhou’ (J-PCNA type), and ‘Mopanshi’ (non-PCNA type), were sampled. Two members of ALDH2 family genes, DkALDH2a and DkALDH2b, were isolated from ‘Eshi 1’ persimmon fruit. Gene expression patterns indicated that they may be involved in “coagulation effect”, which leads to natural deastringency in C-PCNA persimmon fruit. Transient expression in ‘Eshi 1’ leaves further demonstrated that their expression can reduce the consumption of soluble tannins and inhibit the astringency removal process. Therefore, DkALDH2a and DkALDH2b are negatively correlated with natural deastringency in C-PCNA persimmon.     

Immobilization of proline-specific endoprotease on nonporous silica nanoparticles functionalized with amino group

Enzyme immobilization is believed to provide an excellent base for increasing environmental tolerance of enzyme and considerable period of time. In this work, a kind of nonporous silica nanoparticles functionalized with amino group was synthesized to immobilize proline-specific endoprotease (PSEP). PSEP is known to specifically cleave peptides (or esters) at the carboxyl side of proline, thus can prevent the formation of haze and prolong the shelf life of beer. After immobilization, the environmental tolerance (temperature and pH, respectively) was obviously improved, and the immobilized enzyme can retain above 90 % of its original activity after 6 uses. Moreover, the immobilized enzyme can effectively prevent the formation of chill-haze using fresh beer fermentation liquid.     

Characterization and high‐yield production of non‐N‐glycosylated recombinant human BCMA‐Fc in Pichia pastoris

B‐cell maturation antigen (BCMA) fused at the C‐terminus to the Fc portion of human IgG1 (BCMA‐Fc) blocks B‐cell activating factor (BAFF) and proliferation‐inducing ligand (APRIL)‐mediated B‐cell activation, leading to immune disorders. The fusion protein has been cloned and produced by several engineering cell lines. To reduce cost and enhance production, we attempted to express recombinant human BCMA‐Fc (rhBCMA‐Fc) in Pichia pastoris under the control of the AOX1 methanol‐inducible promoter. To produce the target protein with uniform molecular weight and reduced immunogenicity, we mutated two predicted N‐linked glycosylation sites. The secretory yield was improved by codon optimization of the target gene sequence. After fed‐batch fermentation under optimized conditions, the highest yield (207 mg/L) of rhBCMA‐Fc was obtained with high productivity (3.45 mg/L/h). The purified functional rhBCMA‐Fc possessed high‐binding affinity to APRIL and dose‐dependent inhibition of APRIL‐induced proliferative activity in vitro through three‐step purification. Thus, this yeast‐derived expression method could be a low‐cost and effective alternative to the production of rhBCMA‐Fc in mammalian cell lines.     

Toxic effects of high copper content on physiological processes in <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L.

The aim of this study was to determine the impact of increased copper contents on selected physiological processes in oneyear-old Pinus sylvestris L. needles from a former German timber storage area in Warcino Forest District, a subject to an environmental quality survey. Samples were collected from the area with the high copper content in the soil. The control area was a nearby pine tree stand showing unimpeded growth. The significant growth inhibition was found in dwarf shoots and whole needles, increased water content, and reduced dry mass were also observed. The chlorophyll content was lowered, while 20% higher electrolyte leakage was found. Chlorophyll a fluorescence indicated only higher values of the nonphotochemical quenching in P. sylvestris from the Cu-site. Significant differences were shown in the rate of gas exchange measured by changes in carbon dioxide or oxygen concentration. The intensity of photosynthesis in needles of P. sylvestris from the Cu-site measured by CO₂ uptake was considerably higher than that of oxygen production. The rate of respiration in the needles from the Cu-site measured by the amount of released CO₂ was higher only by 15%, while according to O₂ consumed, the rate increased by 30% in relation to the control. Our results suggest that the copper accumulation in P. sylvestris needles affected the morphology and physiology of the studied organs.     

The Hog1-like MAPK Mpk3 collaborates with Hog1 in response to heat shock and functions in sustaining the biological control potential of a fungal insect pathogen

The mitogen-activated protein kinase (MAPK) Mpk3/MpkC resembles the MAPK Hog1 but does not necessarily function in some filamentous fungi. Here, we compared functions of Mpk3 and Hog1 in Beauveria bassiana, a filamentous fungal insect pathogen, by multi-phenotypic analyses of their single/double deletion mutants. Growth defects of Δmpk3 were moderate on all 14 minimal media with different carbon or nitrogen sources and less severe than those of Δhog1 on most media tested. The double deletion mutant suffered significantly more severe growth defects than those observed in Δmpk3 and Δhog1, suggesting overlapping and collaborative roles of Mpk3 and Hog1 in uptake of six carbon and four nitrogen sources during normal growth. Despite little impact on conidiation capacity, mpk3 deletion slowed down conidial germination as much as hog1 or double deletion. Conidial resistance to UV-B irradiation decreased less in Δmpk3 than in Δhog1 or in the double mutant. The fungal virulence was similarly attenuated for all deletion mutants against Galleria mellonella larvae through normal cuticle infection. Intriguingly, the Δmpk3 mutant displayed null response to high osmolarity and fludioxonil fungicide, to which both Δhog1 and double mutants were hypersensitive and highly resistant, respectively, but it was more sensitive to a 3-h heat shock at 40 °C than Δhog1 during normal incubation. Western blot hybridization demonstrated that Mpk3 could collaborate with Hog1 in response to heat shock rather than to the chemical stresses. Altogether, Mpk3 collaborates with Hog1 only in response to heat shock and functions in sustaining the pest control potential of B. bassiana.