Precision Determination of the Neutral Weak Form Factor of ^{48}Ca

We report a precise measurement of the parity-violating (PV) asymmetry A_{PV} in the elastic scattering of longitudinally polarized electrons from ^{48}Ca. We measure A_{PV}=2668±106(stat)±40(syst) parts per billion, leading to an extraction of the neutral weak form factor F_{W}(q=0.8733  fm^{-1})=0.1304±0.0052(stat)±0.0020(syst) and the charge minus the weak form factor F_{ch}-F_{W}=0.0277±0.0055. The resulting neutron skin thickness R_{n}-R_{p}=0.121±0.026(exp)±0.024(model)  fm is relatively thin yet consistent with many model calculations. The combined CREX and PREX results will have implications for future energy density functional calculations and on the density dependence of the symmetry energy of nuclear matter.

[Expression and clinical significance of COL1A1 and COL1A2 genes in malignant pleural mesothelioma tissues]

Objective: To investigate the expression levels and clinical significance of collagen typeⅠ α1 chain (COL1A1) and collagen type Ⅰ α2 chain (COL1A2) in malignant pleural mesothelioma (MPM) tissues. Methods: In January 2020, MPM tissues and adjacent normal pleural tissues were collected from 26 MPM patients, and the expression levels of COL1A1 and COL1A2 genes in the tissues were determined by quantitative reverse transcription PCR, and the efficacy of both levels in diagnosing MPM was assessed using receiver operating characteristic (ROC) curves. The relationship between COL1A1 and COL1A2 gene expression and clinicopathological features was analyzed by the Cancer Genome Atlas (TCGA) database, and the relationship between the expression levels of both and overall survival (OS) and disease-free progression survival (DFS) of MPM patients was dynamically analyzed by gene expression profiling, and the factors affecting the prognosis of MPM patients were explored by Cox proportional risk regression model. The TIMER 2.0 platform was used to explore the relationship between COL1A1 and COL1A2 gene expression in MPM and tumor immune infiltrative cells. Results: Compared with normal pleural tissues, the expression of COL1A1 and COL1A2 genes was significantly increased in MPM tissues (P<0.01) , and their expression was positively correlated (P<0.001) . The ROC curves showed that the area under the curve for COL1A1 and COL1A2 expression levels diagnostic of MPM was 0.900 and 0.897, respectively. The expression of COL1A1 gene was correlated with tumor type in MPM patients (P<0.05) , and COL1A2 gene expression was correlated with T stage in MPM patients (P<0.05) . Both COL1A1 and COL1A2 gene expression were associated with OS in MPM patients (Logrank P<0.05) , but there was no significant correlation with DFS (Logrank P>0.05) . Cox multivariate analysis showed that patients with high COL1A1 and COL1A2 gene expression and biphasic mixed MPM had a higher risk of death (P<0.05) . TIMER 2.0 platform analysis showed that COL1A1 and COL1A2 gene expression in MPM patients was positively correlated with macrophages, COL1A2 gene expression in MPM was negatively correlated with neutrophils (P<0.05) . Conclusion: High expression of COL1A1 and COL1A2 genes in MPM tissues is valuable for diagnosis, disease prediction and prognostic assessment of MPM, and both may jointly contribute to the development of MPM.

Down-regulation of PvSAMS impairs S-adenosyl-L-methionine and lignin biosynthesis, and improves cell wall digestibility in switchgrass

S-adenosyl- l-methionine (SAM) is the methyl donor involved in the biosynthesis of guaiacyl (G) and syringyl (S) lignins in vascular plants. SAM is synthesized from methionine through the catalysis of the enzyme S-adenosylmethionine synthase (SAMS). However, the detailed function of SAMS in lignin biosynthesis has not been widely investigated in plants, particularly in monocot species. In this study, we identified PvSAMS genes from switchgrass (Panicum virgatum L.), an important dual-purpose fodder and biofuel crop, and generated numerous transgenic switchgrass lines through PvSAMS RNA interference technology. Down-regulation of PvSAMS reduced the contents of SAM, G-lignins, and S-lignins in the transgenic switchgrass. The methionine and glucoside derivatives of caffeoyl alcohol were found to accumulate in the transgenic plants. Moreover, down-regulation of PvSAMS in switchgrass resulted in brownish stems associated with reduced lignin content and improved cell wall digestibility. Furthermore, transcriptomic analysis revealed that most sulfur deficiency-responsive genes were differentially expressed in the transgenic switchgrass, leading to a significant increase in total sulfur content; thus implying an important role of SAMS in the methionine cycle, lignin biosynthesis, and sulfur assimilation. Taken together, our results suggest that SAMS is a valuable target in lignin manipulation, and that manipulation of PvSAMS can simultaneously regulate the biosynthesis of SAM and methylated monolignols in switchgrass.

Transcriptional and Metabolic Responses of Maize Shoots to Long-Term Potassium Deficiency

Potassium is important for plant growth and crop yield. However, the effects of potassium (K⁺) deficiency on silage maize biomass yield and how maize shoot feedback mechanisms of K⁺ deficiency regulate whole plant growth remains largely unknown. Here, the study aims to explore the maize growth, transcriptional and metabolic responses of shoots to long-term potassium deficiency. Under the K⁺ insufficiency condition, the biomass yield of silage maize decreased. The transcriptome data showed that there were 922 and 1,107 differential expression genes in DH605 and Z58, respectively. In the two varieties, 390 differently expressed overlapping genes were similarly regulated. These genes were considered the fundamental responses to K⁺ deficiency in maize shoots. Many stress-induced genes are involved in transport, primary and secondary metabolism, regulation, and other processes, which are involved in K⁺ acquisition and homeostasis. Metabolic profiles indicated that most amino acids, phenolic acids, organic acids, and alkaloids were accumulated in shoots under K⁺ deficiency conditions and part of the sugars and sugar alcohols also increased. It revealed that putrescine and putrescine derivatives were specifically accumulated under the K⁺ deficiency condition, which may play a role in the feedback regulation of shoot growth. These results confirmed the importance of K⁺ on silage maize production and provided a deeper insight into the responses to K⁺ deficiency in maize shoots.

New Measurements of the Beam-Normal Single Spin Asymmetry in Elastic Electron Scattering over a Range of Spin-0 Nuclei

We report precision determinations of the beam-normal single spin asymmetries (A_{n}) in the elastic scattering of 0.95 and 2.18 GeV electrons off ^{12}C, ^{40}Ca, ^{48}Ca, and ^{208}Pb at very forward angles where the most detailed theoretical calculations have been performed. The first measurements of A_{n} for ^{40}Ca and ^{48}Ca are found to be similar to that of ^{12}C, consistent with expectations and thus demonstrating the validity of theoretical calculations for nuclei with Z≤20. We also report A_{n} for ^{208}Pb at two new momentum transfers (Q^{2}) extending the previous measurement. Our new data confirm the surprising result previously reported, with all three data points showing significant disagreement with the results from the Z≤20 nuclei. These data confirm our basic understanding of the underlying dynamics that govern A_{n} for nuclei containing ≲50 nucleons, but point to the need for further investigation to understand the unusual A_{n} behavior discovered for scattering off ^{208}Pb.

[Short-term efficacy of anti-IgE monoclonal antibody in patients with recurrent chronic rhinosinusitis with nasal polyps combined with asthma]

Objective: To investigate the short-term efficacy of anti-IgE monoclonal antibody (Omalizumab) in the treatment of recurrent chronic rhinosinusitis with nasal polyps (CRSwNP) complicated with asthma. Methods: Patients with recurrent CRSwNP and comorbid asthma in Beijing TongRen Hospital from May to December of 2020 were continuously recruited and received a 4-month therapy of stable background treatment plus Omalizumab. Results of visual analog scales (VAS) of nasal symptoms, sino-nasal outcome test-22 (SNOT 22) and nasal polyp scores were collected at baseline and post-treatment (1, 2, 3 and 4 months after treatment). Blood routine tests, total nasal resistances (TNR), minimum cross-sectional areas (MCA), total nasal cavity volumes (NCV), forced expiratory volumes in one second (FEV1)/forced vital capacity (FVC) and adverse events were collected at baseline and 4 months after treatment. All results were evaluated for short-term efficacy of Omalizumab. GraphPad Prism 8.2.1 was used for statistic analysis. Results: Ten patients were collected, including 3 males and 7 females, aged (41.13±12.64) years old (x¯±s). Compared to results at baseline, the VAS scores of nasal obstruction, rhinorrhea, hyposmia and headache after 4 months treatment were significantly decreased (1.80±1.48 vs 6.70±2.83, 2.40±1.27 vs 6.40±3.44, 2.70±2.91 vs 8.20±2.25, 0.60±1.08 vs 3.60±2.72, t value was 5.045, 4.243, 5.312, 3.402, respectively, all P<0.01). The scores of SNOT-22 (25.6±20 vs 61.3±33.32, t=4.127, P=0.002 6), nasal polyp scores (2.20±0.92 vs 4.60±0.84, t=9.000, P<0.01) and the count and percentage of eosinophils in peripheral blood were significantly decreased ((94.10±97.78)×10⁹/L vs (360.00±210.80)×10⁹/L, (32.90±27.06)% vs (64.40±20.73)%, t value was 3.678, 2.957, respectively, all P<0.05). NCV (0-5 cm and 0-7 cm) of patients were improved from baseline ((12.62±2.84) cm³ vs (10.40±2.09) cm³, (27.50±14.15) cm³ vs (16.81±6.40) cm³, t value was 2.371, 2.445, respectively, all P<0.05). Conclusions: The 4-month treatment of Omalizumab can significantly improve the nasal symptoms and quality of life of patients with recurrent CRSwNP complicated with asthma, shrink nasal polyps size and reduce the number of peripheral blood eosinophils. Omalizumab can be used as an alternative therapy for refractory CRSwNP patients in the future.

[Effects of Astragaloside Ⅳ on exosome secretion and its microRNA-126 expression in human endothelial progenitor cells]

Objective: To investigate the effects of Astragaloside Ⅳ on the secretion of exosomes in human endothelial progenitor cells (EPCs) and the expression of microRNA (miRNA)-126 in exosomes. Methods: The umbilical cord blood from one healthy full-term newborn from the Department of Obstetrics and Gynecology of the First Affiliated Hospital of Hunan University of Traditional Chinese Medicine in 2019 was harvested for isolating mononuclear cells by density gradient centrifugation and cultured for 7 days. Morphological observation was performed during this period. Cells of the third passage were collected for identification by CD31 immunomagnetic bead sorting and double fluorescence staining. According to the random number table, the identified EPCs were divided into Astragaloside Ⅳ group and phosphate buffer solution (PBS) group. The cells in Astragaloside Ⅳ group were cultured with Astragaloside Ⅳ in final mass concentration of 100 mg/L for 24 hours, and the cells in PBS group were cultured with the same volume of PBS for 24 hours. After culture, the exosomes from the cell culture supernatant of the two groups were collected, and the expressions of characteristic markers of exosomes CD9, CD63, and CD81 were detected by Western blotting, the morphology of EPC exosomes (EPC-Exos) was observed under transmission electron microscope, and the particle size of EPC-Exos was detected by nanoparticle tracking analysis technique. The concentration of EPC-Exos was determined by dioctyl butyric acid method (the sample number was 3), and the expressions of miRNA-126-3p and miRNA-126-5p related to angiogenesis in EPC-Exos were determined by reverse transcription polymerase chain reaction (the sample number was 3). Data were statistically analyzed with independent sample t test. Results: (1) On the 4th day of culture, the cells began to adhere to the wall, and the multi-forms such as circle, fusiform, and strip appeared at the same time. On the 7th day of culture, the edge of the cells was clear and arranged like a paving stone, the central cells were round, and the surrounding cells were fusiform. (2) CD31 immunomagnetic beads sorting method identification showed that the membrane was stained with green fluorescence and the nucleus was stained with blue fluorescence. Double fluorescence staining method showed that the cells were orange-yellow. The cells were identified as EPCs. (3) After 24 hours of culture, the expressions of CD9, CD63, and CD81 in EPC-Exos were all positive, confirming that EPC-Exos were extracted successfully in this experiment. (4) After 24 hours of culture, the EPC-Exos of the two groups showed round membrane vesicles, and there was no significant difference in morphology. (5) After 24 hours of culture, the particle size of 98.7% EPC-Exos in Astragaloside Ⅳ group was 84.7 to 143.1 nm, and that of 98.0% EPC-Exos in PBS group was 88.7 to 123.5 nm. (6) After 24 hours of culture, the mass concentration of EPC-Exos in Astragaloside Ⅳ group was (310±5) μg/mL, which was significantly higher than (257±5) μg/mL in PBS group, t=13.369, P<0.01. (7) After 24 hours of culture, there were more miRNA-126-3p (t=16.062, P<0.01) and miRNA-126-5p (t=3.252, P<0.05) in EPC-Exos of Astragaloside Ⅳ group than in PBS group. Conclusions: Astragaloside Ⅳ can improve the function of human EPC secretory exosomes, and the secreted exosomes are loaded with miRNA-126.

Characterization of Two New brown midrib1 Mutations From an EMS-Mutagenic Maize Population for Lignocellulosic Biomass Utilization

Gene mutations linked to lignin biosynthesis are responsible for the brown midrib (bm) phenotypes. The bm mutants have a brown-reddish midrib associated with changes in lignin content and composition. Maize bm1 is caused by a mutation of the cinnamyl alcohol dehydrogenase gene ZmCAD2. Here, we generated two new bm1 mutant alleles (bm1-E1 and bm1-E2) through EMS mutagenesis, which contained a single nucleotide mutation (Zmcad2-1 and Zmcad2-2). The corresponding proteins, ZmCAD2-1 and ZmCAD2-2 were modified with Cys103Ser and Gly185Asp, which resulted in no enzymatic activity in vitro. Sequence alignment showed that CAD proteins have high similarity across plants and that Cys103 and Gly185 are conserved in higher plants. The lack of enzymatic activity when Cys103 was replaced for other amino acids indicates that Cys103 is required for its enzyme activity. Enzymatic activity of proteins encoded by CAD genes in bm1-E plants is 23-98% lower than in the wild type, which leads to lower lignin content and different lignin composition. The bm1-E mutants have higher saccharification efficiency in maize and could therefore provide new and promising breeding resources in the future.

MiR-663a, regulated by lncRNA GAS5, contributes to osteosarcoma development through targeting MYL9

Osteosarcoma is characterized by high malignancy and high metastasis rate, resulting in high mortality and disability. MiR-663a has been reported in a variety of tumors to promote tumorigenesis. However, miR-663a has not been reported in the pathogenesis of osteosarcoma. Bioinformatics analysis and experiments including real-time quantitative polymerase chain reaction (RT-qPCR), luciferase reporter, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Western blot, RNA immunoprecipitation, and flow cytometry assay were applied to explore the function and mechanism of miR-663a in MG63, U2OS, Saos-2, SF-86, and hFOB1.19 cells. In this study, we found that miR-663a is highly expressed in osteosarcoma. At the same time, we discovered that miR-663a facilitates cell proliferation and migration, whereas suppresses cell apoptosis in osteosarcoma. Through a series of biological experiments, it was found that miR-663a regulates the cellular process in osteosarcoma by modulating the expression of MYL9. In addition, we also found that long noncoding RNA (lncRNA) GAS5 serves as a molecular sponge for miR-663a and regulates the progression of osteosarcoma via the ceRNA mechanism. We uncover that miR-663a promotes osteosarcoma development through targeting MYL9, which was regulated by lncRNA GAS5.

[Clinical application of self-made drainage tubes in different layers of soft tissue for negative-pressure wound therapy in 33 patients]

From January 2014 to June 2018, 28 patients with different types of deep soft tissue injury or infection were admitted to the Affiliated Jiangyin Hospital of Medical College of Southeast University; 5 patients were admitted to the Zhengzhou First People's Hospital. There were 24 males and 9 females, aged 18-89 (40±20) years. Disposable suction tubes with holes cut on side walls were used as self-made drainage tubes. The authors placed the self-made drainage tubes on different deep soft tissue layers and wound surfaces after debridement. The effective drainage sections of the wound surface drainage tubes were wrapped with silver ion antimicrobial functional active dressings. Bio-permeable membrane was used to close the operative area. The drainage tubes in the deep layer of wound and wound surface were connected in parallel by a tee and connected to wall-hanging medical negative-pressure suction device to conduct negative-pressure wound treatment at -20.0 to -10.6 kPa. The deep drainage tubes were usually removed or changed 4 or 5 days after surgery.The drainage tubes in the wound surface were synchronously replaced when removing or replacing he drainage tubes in the deep layer of wound. On 4 to 15 days after surgery, the deep drainage tubes were removed. On 8 to 25 days after surgery, the wound surface drainage tubes were removed. Then the treatment was changed to a conventional dressing change until the wounds were completely healed or the wound bed was ready for skin grafts or tissue flaps. The indwelling time of deep drainage tubes in this group of patients was (6.2±2.8) days, and the indwelling time of wound surface drainage tubes was (12.0±3.0) days. The wound healing time was (22±5) days, the hospital stay time was (29±7) days, and wound bacteria were reduced from 6 species and 11 strains before treatment to 3 species and 4 strains after treatment. No adverse events such as wound bleeding, irritative pain, and chronic sinus occurred during treatment. Twenty-three patients were followed up for 13 to 28 months, no treatment-related complications were observed.

The tumor suppressor NOR1 suppresses cell growth, invasiveness, and tumorigenicity in glioma

Oxidored-nitro domain-containing protein 1 (NOR1) is a tumor suppressor downregulated in various human cancers, including nasopharyngeal carcinoma (NPC), lung cancer, and testicular cancer. NOR1 protein is highly expressed in the normal brain; however, its role in brain tumors remains unknown. In this study, we demonstrated that the NOR1 protein level was decreased in glioma tissue samples as compared to its normal counterpart. Exogenously expressed NOR1 protein in glioma U251 cells inhibits tumor cell proliferation, migration, and invasion. Re-expression of NOR1 induced cell cycle S to G2 phase arrest and suppressed its tumorigenicity in nude mice. Overexpression of NOR1 in U251 cells also led to a decrease of Ki67 expression in xenografts. Transcriptomic analysis revealed that NOR1 expression altered the expression of genes favored cell proliferation. Among the differentially expressed genes, FOXR2, a member of the FOX gene family, which promotes glioma progression, was decreased in NOR1 expressing cells. The downregulation of FOXR2 by NOR1 was validated in vitro and in vivo. Our findings suggest for the first time that NOR1 suppresses glioma progression via modulating the FOXR2 expression.

Palmatine alleviates hyperalgesia by inhibiting the expression of calcitonin gene-related peptide in the trigeminal ganglion of rats with chronic constriction injury of the infraorbital nerve

Trigeminal neuralgia is one of the most common of the neuropathic pains, and it can seriously influence patients' quality of life. Calcitonin gene-related peptide (CGRP) is a type of nociceptive neurotransmitter that is expressed in neurons of the trigeminal ganglion and plays a major part in transmitting pain. The rat model of trigeminal neuralgia was established by causing a chronic constriction injury of the infraorbital nerve (CCI-ION). Male Sprague-Dawley rats (n=24) were randomly divided into a sham control group (sham, n=6), sham-treated with palmatine group (sham+palmatine, n=6), trigeminal nerve model group (TN, n=6), and trigeminal nerve treated with palmatine group (TN+palmatine, n=6). Fifteen days after the operation the mechanical response threshold was decreased in the TN group compared with the sham group. From postoperative day 7 to day 15, the mechanical response threshold in the TN+palmatine group significantly increased compared with the TN group. On postoperative day 15 the results of quantitative polymerase chain reaction (qPCR), immunohistochemical staining, and western blotting showed an obvious increase in expression of CGRP and its receptors, serum concentrations of interleukin-1β (IL-1β), and tumour necrosis factor-α (TNF-α), and phosphorylation of protein kinase C (PKC) in the trigeminal ganglia of the TN group compared with the sham group, but these increases could be down-regulated by treatment with palmatine. Palmatine might therefore have therapeutic potential for the treatment of trigeminal neuralgia by inhibiting the expression of CGRP and its receptors in trigeminal ganglia, suppressing the serum concentrations of IL-1β and TNF-α, and decreasing the phosphorylation of PKC in the trigeminal ganglia of affected rats.

Emission and biosynthesis of volatile terpenoids from the plasmodial slime mold Physarum polycephalum

Terpene synthases (TPSs) are pivotal enzymes for the production of diverse terpenes, including monoterpenes, sesquiterpenes, and diterpenes. In our recent studies, dictyostelid social amoebae, also known as cellular slime molds, were found to contain TPS genes for making volatile terpenes. For comparison, here we investigated Physarum polycephalum, a plasmodial slime mold also known as acellular amoeba. Plasmodia of P. polycephalum grown on agar plates were found to release a mixture of volatile terpenoids consisting of four major sesquiterpenes (α-muurolene, (E)-β-caryophyllene, two unidentified sesquiterpenoids) and the monoterpene linalool. There were no qualitative differences in terpenoid composition at two stages of young plasmodia. To understand terpene biosynthesis, we analyzed the transcriptome and genome sequences of P. polycephalum and identified four TPS genes designated PpolyTPS1-PpolyTPS4. They share 28-73% of sequence identities. Full-length cDNAs for the four TPS genes were cloned and expressed in Escherichia coli to produce recombinant proteins, which were tested for sesquiterpene synthase and monoterpene synthase activities. While neither PpolyTPS2 nor PpolyTPS3 was active, PpolyTPS1 and PpolyTPS4 were able to produce sesquiterpenes and monoterpenes from the respective substrates farnesyl diphosphate and geranyl diphosphate. By comparing the volatile profile of P. polycephalum plasmodia and the in vitro products of PpolyTPS1 and PpolyTPS4, it was concluded that most sesquiterpenoids emitted from P. polycephalum were attributed to PpolyTPS4. Phylogenetic analysis placed the four PpolyTPSs genes into two groups: PpolyTPS1 and PpolyTPS4 being one group that was clustered with the TPSs from the dictyostelid social amoeba and PpolyTPS2 and PpolyTPS3 being the other group that showed closer relatedness to bacterial TPSs. The biological role of the volatile terpenoids produced by the plasmodia of P. polycephalum is discussed.

A small proton charge radius from an electron-proton scattering experiment

Elastic electron-proton scattering (e-p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, r_p. In 2010, a new method using muonic hydrogen atoms¹ found a substantial discrepancy compared with previous results², which became known as the 'proton radius puzzle'. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements conducted on ordinary hydrogen^3,4. Here we report on the proton charge radius experiment at Jefferson Laboratory (PRad), a high-precision e-p experiment that was established after the discrepancy was identified. We used a magnetic-spectrometer-free method along with a windowless hydrogen gas target, which overcame several limitations of previous e-p experiments and enabled measurements at very small forward-scattering angles. Our result, r_p = 0.831 ± 0.007_stat ± 0.012_syst femtometres, is smaller than the most recent high-precision e-p measurement⁵ and 2.7 standard deviations smaller than the average of all e-p experimental results⁶. The smaller r_p we have now measured supports the value found by two previous muonic hydrogen experiments^1,7. In addition, our finding agrees with the revised value (announced in 2019) for the Rydberg constant⁸-one of the most accurately evaluated fundamental constants in physics.

Latrophilin mediates insecticides susceptibility and fecundity through two carboxylesterases, esterase4 and esterase6, in Tribolium castaneum

Latrophilin (LPH) is known as an adhesion G-protein-coupled receptor which involved in multiple physiological processes in organisms. Previous studies showed that lph not only involved the susceptibility to anticholinesterase insecticides but also affected fecundity in Tribolium castaneum. However, its regulatory mechanisms in these biological processes are still not clear. Here, we identified two potential downstream carboxylesterase (cce) genes of Tclph, esterase4 and esterase6, and further characterized their interactions with Tclph. After treatment of T. castaneum larvae with carbofuran or dichlorvos insecticides, the transcript levels of Tcest4 and Tcest6 were significantly induced from 12 to 72 h. RNAi against Tcest4 or Tcest6 led to the higher mortality compared with the controls after the insecticides treatment, suggesting that these two genes play a vital role in detoxification of insecticides in T. castaneum. Furthermore, with insecticides exposure to Tclph knockdown beetles, the expression of Tcest4 was upregulated but Tcest6 was downregulated, indicating that beetles existed a compensatory response against the insecticides. Additionally, RNAi of Tcest6 resulted in 43% reductions in female egg laying and completely inhibited egg hatching, which showed the similar phenotype as that of Tclph knockdown. These results indicated that Tclph affected fecundity by positively regulating Tcest6 expression. Our findings will provide a new insight into the molecular mechanisms of Tclph involved in physiological functions in T. castaneum.

Terpene Synthase Genes Originated from Bacteria through Horizontal Gene Transfer Contribute to Terpenoid Diversity in Fungi

Fungi are successful eukaryotes of wide distribution. They are known as rich producers of secondary metabolites, especially terpenoids, which are important for fungi-environment interactions. Horizontal gene transfer (HGT) is an important mechanism contributing to genetic innovation of fungi. However, it remains unclear whether HGT has played a role in creating the enormous chemical diversity of fungal terpenoids. Here we report that fungi have acquired terpene synthase genes (TPSs), which encode pivotal enzymes for terpenoid biosynthesis, from bacteria through HGT. Phylogenetic analysis placed the majority of fungal and bacterial TPS genes from diverse taxa into two clades, indicating ancient divergence. Nested in the bacterial TPS clade is a number of fungal TPS genes that are inferred as the outcome of HGT. These include a monophyletic clade of nine fungal TPS genes, designated as BTPSL for bacterial TPS-like genes, from eight species of related entomopathogenic fungi, including seven TPSs from six species in the genus Metarhizium. In vitro enzyme assays demonstrate that all seven BTPSL genes from the genus Metarhizium encode active enzymes with sesquiterpene synthase activities of two general product profiles. By analyzing the catalytic activity of two resurrected ancestral BTPSLs and one closely related bacterial TPS, the trajectory of functional evolution of BTPSLs after HGT from bacteria to fungi and functional divergence within Metarhizium could be traced. Using M. brunneum as a model species, both BTPSLs and typical fungal TPSs were demonstrated to be involved in the in vivo production of terpenoids, illustrating the general importance of HGT of TPS genes from bacteria as a mechanism contributing to terpenoid diversity in fungi.

NAKα2 inhibits fibrosis formation and protects against cardiomyocyte hypertrophy by suppressing hypertrophy associated molecules and activating LTCC/NCX signaling pathway

OBJECTIVE

Cardiomyocyte hypertrophy is considered to be a compensatory process of heart suffering from pathological damages. This study aimed to evaluate effects of Na+/K+ APTaseα2 (NAKα2) on isoprenaline (ISO) induced cardiomyocyte hypertrophy.

MATERIALS AND METHODS

Mouse atrial cardiomyocytes were cultured and treated with ISO to establish cardiomyocyte hypertrophy model. NAKα2 over-expression and small interfere RNA (siRNA) plasmids were constructed and transfected to cardiomyocytes. Influx Ca2+ ([Ca2+]i) was measured using flow cytometry method. Fibrosis formation was examined with Masson staining. Transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) staining was used to examine apoptosis. Major histocompatibility complex β (β-MHC), atrial natriuretic peptides (ANP), B-type natriuretic peptides (BNP) were evaluated with quantitative Real-time PCR (qRT-PCR). Western blot was used to detect β-MHC, ANP, BNP, Na+/Ca2+ exchanger (NCX) and L-type calcium channel (LTCC).

RESULTS

NAKα2 significantly inhibited NCX and LTCC expression compared to that in ISO-treated cardiomyocytes (p<0.05). NAKα2 significantly suppressed expression of β-MHC, ANP and BNP compared to that in ISO-treated cardiomyocytes (p<0.05). NAKα2 significantly alleviated fibrosis formation and inhibited apoptosis compared to that in ISO-treated cardiomyocytes (p<0.05). NAKα2 reduced intracellular calcineurin and activated phosphorylation of calcineurin-nuclear factor of activated T cells (NFAT) compared to ISO-treated cardiomyocytes (p<0.05). NAKα2 significantly strengthened effects of Klotho on ISO-induced up-regulation of hypertrophy associated molecules (p<0.05) by activating LTCC and NCX. Comparing to ISO-treated cardiomyocytes, NAKα2 combining Klotho treatment exhibited significantly better improvement of Ca2+ influx, alleviation of fibrosis and reduction of apoptosis by triggering LTCC/NCX signaling pathway.

CONCLUSIONS

Over-expression of NKAα2 suppressed fibrosis formation and protected against cardiomyocyte hypertrophy by inhibiting hypertrophy associated molecules, alleviating apoptosis and activating LTCC/NCX signaling pathway.

Mutation of 4-coumarate: coenzyme A ligase 1 gene affects lignin biosynthesis and increases the cell wall digestibility in maize brown midrib5 mutants

BACKGROUND

Maize brown midrib (bm) mutants associated with impaired lignin biosynthesis are a potential source for the breed of novel germplasms with improved cell wall digestibility. The spontaneous bm5 mutants had been identified since 2008. However, the gene responsible for the bm5 locus, and the comprehensive effects of bm5 mutation on lignin biosynthesis, soluble phenolics accumulation, and cell wall degradation have yet to be elucidated.

RESULTS

The bm5 locus was identified to encode a major 4-coumarate: coenzyme A ligase (Zm4CL1) through analyzing MutMap-assisted gene mapping data. Two alleles of Zm4CL1 isolated from bm5 mutants contained two transposons inserted in the first exon and the second intron, respectively, and consequently, the activities of 4CLs in the crude enzyme extracts from bm5 midribs were reduced by 51-62% compared with the wild type. Furthermore, five 4CLs were retrieved from maize genome, and Zm4CL1 was the most highly expressed one in the lignified tissues. Mutation of Zm4CL1 mainly impeded the biosynthesis of guaiacyl (G) lignins and increased the level of soluble feruloyl derivatives without impacting maize growth and development. Moreover, both neutral detergent fiber digestibility and saccharification efficiency of cell walls were significantly elevated in the bm5 mutant.

CONCLUSIONS

Zm4CL1 was identified as the Bm5 gene, since two independent alleles of Zm4CL1 were associated with the same mutant phenotype. Mutation of Zm4CL1 mainly affected G lignin biosynthesis and soluble feruloyl derivatives accumulation in maize lignified tissues. The reduced recalcitrance of the bm5 mutant suggests that Zm4CL1 is an elite target for cell wall engineering, and genetic manipulation of this gene will facilitate the utilization of crop straw and stover that have to be dealt with for environmental protection.

PM2.5 stimulated the release of cytokines from BEAS-2B cells through activation of IKK/NF-κB pathway

Previous studies indicated that exposure to fine particulate matter (PM_2.5) was related to pulmonary inflammatory diseases through activation of nuclear factor kappa B (NF-κB) signaling pathway to trigger cytokine secretions in human lung carcinoma cells. To investigate the potential mechanisms underlying expression of cytokines via activated NF-κB by PM_2.5, human bronchial epithelial cells (BEAS-2B cells) were treated with PM_2.5 extracts at different concentrations (6, 13, 25, 50, 100, 200, and 400 µg mL^-1) for 6 and 24 h. We found that 100 µg mL^-1 PM_2.5 increased interleukin 6 (IL-6) and IL-8 expression at 24 h (p < 0.05 or p < 0.01). Moreover, 100 µg mL^-1 PM_2.5 upregulated phosphorylated IκB kinase (IKK), p65, and IκBα at 6 h, which could be reversed by the IKK inhibitor Bay11-7082 (p < 0.05 or p < 0.01). The p65 subunit of NF-κB was translocated into the nucleus of the cells treated with 100 µg mL^-1 PM_2.5 at 6 and 24 h. Bay11-7082 partly inhibited PM_2.5-induced increases of IL-6 and IL-8 secretion. The results indicated that PM_2.5 extract increased IL-6 and IL-8 levels in BEAS-2B cells through activation of IKK/NF-κB pathway. Our study will contribute to better understanding of the mechanism of PM_2.5-induced pulmonary inflammatory diseases.