Screening differential circular RNA expression profiles reveals the regulatory role of circMARS in anti-tuberculosis drug-induced liver injury.

Tuberculosis (TB) treatment is plagued by liver damage, which often leads to treatment interruptions. Circular RNAs (circRNAs) are a special class of non-coding RNAs abundant in body fluids with important biological functions. However, the role of circRNA in anti-tuberculosis drug-induced liver injury (ADLI) is unclear. We explored ADLI-specific circRNAs in TB patients using circRNA microarrays and verified circMARS in a cohort of 300 individuals. In addition to the value assessment of circMARS in patients using a receiver operating characteristic (ROC) curve, cell experiments were also performed under the guidance of bioinformatics analyses. In particular, we found that circMARS acts as a miRNA sponge by binding to miRNAs. Compared with the blank group, the expressions of circMARS, KMT2C gene, and EGFR protein in the ADLI group were increased, while miR-6808-5p, miR-6874-3p, and miR-3157-5p were decreased. Furthermore, when si-circMARS was used in the ADLI groups, circMARS demotion manifested the opposite results. Subsequently, a self-controlled cohort of 35 participants was used to verify the circMARS-miR-6808-5p/-6874-3p/-3157-5p-KMT2C-EGFR function axis. Therefore, circMARS may participate in the compensatory repair mechanism of ADLI through the function axis, and may be a potential biomarker for ADLI diagnosis in TB patients.

Three-dimensional architecture of epithelial primary cilia.

We report a complete 3D structural model of typical epithelial primary cilia based on structural maps of full-length primary cilia obtained by serial section electron tomography. Our data demonstrate the architecture of primary cilia differs extensively from the commonly acknowledged 9+0 paradigm. The axoneme structure is relatively stable but gradually evolves from base to tip with a decreasing number of microtubule complexes (MtCs) and a reducing diameter. The axonemal MtCs are cross-linked by previously unrecognized fibrous protein networks. Such an architecture explains why primary cilia can elastically withstand liquid flow for mechanosensing. The nine axonemal MtCs in a cilium are found to differ significantly in length indicating intraflagellar transport processes in primary cilia may be more complicated than that reported for motile cilia. The 3D maps of microtubule doublet-singlet transitions generally display longitudinal gaps at the inner junction between the A- and B-tubules, which indicates the inner junction protein is a major player in doublet-singlet transitions. In addition, vesicles releasing from kidney primary cilia were observed in the structural maps, supporting that ciliary vesicles budding may serve as ectosomes for cell-cell communication.

Phylogenetic and ion-response analyses reveal a relationship between gene expansion and functional divergence in the Ca2+/cation antiporter family in Angiosperms.

KEY MESSAGE: Plant CaCA superfamily genes with higher tendency to retain after WGD are more gene expression and function differentiated in ion-response. Plants and animals face different environmental stresses but share conserved Ca2+ signaling pathways, such as Ca2+/Cation transport. The Ca2+/cation antiporters superfamily (CaCAs) is an ancient and widespread family of ion-coupled cation transporters found in all kingdoms of life. We analyzed the molecular evolution progress of the family through comparative genomics and phylogenetics of CaCAs genes from plants and animals, grouping these genes into several families and clades, and identified multiple gene duplication retention events, particularly in the CAX (H+/cation exchanger), CCX (cation/Ca2+ exchanger), and NCL (Na+/Ca2+ exchanger-like) families. The tendency of duplication retention differs between families and gene clades. The gene duplication events were probably the result of whole-genome duplication (WGD) in plants and might have led to functional divergence. Tissue and ion-response expression analyses revealed that CaCAs genes with more highly differentiated expression patterns are more likely to be retained as duplicates than those with more conserved expression profiles. Phenotype of Arabidopsis thaliana mutants showed that loss of genes with a greater tendency to be retained after duplication resulted in more severe growth deficiency. CaCAs genes in salt-tolerant species tended to inherit the expression characteristics of their most recent common ancestral genes, with conservative ion-response expression. This study indicates a possible evolutionary scheme for cation transport and illustrates distinct fates and a mechanism for the evolution of gene duplicates. The increased copy numbers of genes and divergences in expression might have contributed to the divergent functions of CaCAs protein, allowing plants to cope with environmental stresses and adapt to a larger number of ecological niches.

Regulation of P300 and HDAC1 on endoplasmic reticulum stress in isoniazid-induced HL-7702 hepatocyte injury.

P300 and HDAC1 can be involved in the development of various liver diseases by regulating gene transcription. Endoplasmic reticulum stress (ERS) is one of the main pathways of apoptosis and is activated during inflammatory responses, but the roles of P300 and HDAC1 in ERS in antituberculosis drug-induced liver injury (ADLI) are not clear. This study confirms that isoniazid can change the states of P300 and HDAC1 in HL-7702 hepatocyte metabolism and induce ERS, causing hepatocyte injury and apoptosis. When combined with C646, however, P300 can be reduced. HL-7702 cells were flattened, and the cytoplasm became crinkled. To a certain extent, ERS was relieved, but hepatocytes suffered worse damage, and the rate of cell apoptosis markedly increased. When MS-275 was applied, HDAC1 level was increased, cell fusion appeared, and fluorescence intensity of endoplasmic reticulum was weakened. In addition, ERS was aggravated, but liver injury was relieved, and the apoptosis rate significantly decreased. Therefore, alteration of P300 and HDAC1 status and ERS are involved in ADLI, and changes in P300 and HDAC1 can regulate ERS and then affect cell damage.

FUS Interacts with HSP60 to Promote Mitochondrial Damage.

FUS-proteinopathies, a group of heterogeneous disorders including ALS-FUS and FTLD-FUS, are characterized by the formation of inclusion bodies containing the nuclear protein FUS in the affected patients. However, the underlying molecular and cellular defects remain unclear. Here we provide evidence for mitochondrial localization of FUS and its induction of mitochondrial damage. Remarkably, FTLD-FUS brain samples show increased FUS expression and mitochondrial defects. Biochemical and genetic data demonstrate that FUS interacts with a mitochondrial chaperonin, HSP60, and that FUS translocation to mitochondria is, at least in part, mediated by HSP60. Down-regulating HSP60 reduces mitochondrially localized FUS and partially rescues mitochondrial defects and neurodegenerative phenotypes caused by FUS expression in transgenic flies. This is the first report of direct mitochondrial targeting by a nuclear protein associated with neurodegeneration, suggesting that mitochondrial impairment may represent a critical event in different forms of FUS-proteinopathies and a common pathological feature for both ALS-FUS and FTLD-FUS. Our study offers a potential explanation for the highly heterogeneous nature and complex genetic presentation of different forms of FUS-proteinopathies. Our data also suggest that mitochondrial damage may be a target in future development of diagnostic and therapeutic tools for FUS-proteinopathies, a group of devastating neurodegenerative diseases.

EXO70A1-mediated vesicle trafficking is critical for tracheary element development in Arabidopsis.

Exocysts are highly conserved octameric complexes that play an essential role in the tethering of Golgi-derived vesicles to target membranes in eukaryotic organisms. Genes encoding the EXO70 subunit are highly duplicated in plants. Based on expression analyses, we proposed previously that individual EXO70 members may provide the exocyst with functional specificity to regulate cell type- or cargo-specific exocytosis, although direct evidence is not available. Here, we show that, as a gene expressed primarily during tracheary element (TE) development, EXO70A1 regulates vesicle trafficking in TE differentiation in Arabidopsis thaliana. Mutations of EXO70A1 led to aberrant xylem development, producing dwarfed and nearly sterile plants with very low fertility, reduced cell expansion, and decreased water potential and hydraulic transport. Grafting of a mutant shoot onto wild-type rootstock rescued most of these aboveground phenotypes, while grafting of a wild-type shoot to the mutant rootstock did not rescue the short root hair phenotype, consistent with the role of TEs in hydraulic transport from roots to shoots. Histological analyses revealed an altered pattern of secondary cell wall thickening and accumulation of large membrane-bound compartments specifically in developing TEs of the mutant. We thus propose that EXO70A1 functions in vesicle trafficking in TEs to regulate patterned secondary cell wall thickening.

Effects of hypoxic preconditioning on synaptic ultrastructure in mice.

Hypoxic preconditioning (HPC) elicits resistance to more drastic subsequent insults, which potentially provide neuroprotective therapeutic strategy, but the underlying mechanisms remain to be fully elucidated. Here, we examined the effects of HPC on synaptic ultrastructure in olfactory bulb of mice. Mice underwent up to five cycles of repeated HPC treatments, and hypoxic tolerance was assessed with a standard gasp reflex assay. As expected, HPC induced an increase in tolerance time. To assess synaptic responses, Western blots were used to quantify protein levels of representative markers for glia, neuron, and synapse, and transmission electron microscopy was used to examine synaptic ultrastructure and mitochondrial density. HPC did not significantly alter the protein levels of astroglial marker (GFAP), neuron-specific markers (GAP43, Tuj-1, and OMP), synaptic number markers (synaptophysin and SNAP25) or the percentage of excitatory synapses versus inhibitory synapses. However, HPC significantly affected synaptic curvature and the percentage of synapses with presynaptic mitochondria, which showed concomitant change pattern. These findings demonstrate that HPC is associated with changes in synaptic ultrastructure.

The Aspergillus fumigatus ß-1,3-glucanosyltransferase Gel7 plays a compensatory role in maintaining cell wall integrity under stress conditions.

Aspergillus fumigatus is an opportunistic fungal pathogen that causes fatal invasive aspergillosis among immunocompromised patients. The cell wall ß-1,3-glucan is mainly elongated by ß-1,3-glucanosyltransferase Gel family, which is vital for growth and virulence of A. fumigatus. Although seven members of Gels have been annotated, only Gel1, Gel2 and Gel4 were characterized. In this study, the function of Gel7 was analyzed for the first time, by constructing Δgel7, Δgel7Δcwh41 and Δgel1Δgel7Δcwh41 separately. Disruption of gel7 alone did not result in any obvious phenotype except an abnormality in conidia formation, whereas Δgel7Δcwh41 and Δgel1Δgel7Δcwh41 exhibited abnormal conidiogenesis, a heat-induced delay of germination and a severe decrease in ß-1,3-glucan content. Our results suggested that the A. fumigatus ß-1,3-glucanosyltransferase Gel7 was involved in conidiation and was compensated for the cell wall ß-1,3-glucan defects when Gel1 and Gel2 lost their functions, especially at an elevated temperature.

Enhancement of pulsed laser ablation in environmentally friendly liquid.

Enhancement of pulsed laser ablation can be achieved in acetic acid as an environmentally friendly liquid. This paper evaluates microholes and textured features induced by a nanosecond pulsed laser under different processing circumstances. The microholes are fabricated by laser drilling in acetic acid and found to be 100% deeper than in air. The textured features achieved in the liquid demonstrate a higher content of Copper and a lower content of Oxygen. The improvement of laser ablation efficiency in the liquid is attributed to the strong confinement of plasma plume accompanying with shockwave and cavitation bubbles. Meanwhile, the laser enhanced chemical etching by the weak acid plays a critical role.

Fabrication of ultraviolet-curable adhesive bottle-like microresonators by wetting and photocuring.

This work presents a remarkably simple method for the fabrication of ultraviolet (UV)-curable adhesive bottle-like microresonators (BLMRs). The main fabrication process involves two steps: (1) creating liquid bottle-like microcavities along the taper waist of an optical fiber taper under interfacial tension and (2) curing the liquids into solids by UV light irradiation. The shape of the BLMRs can be fitted with a truncated harmonic-oscillator profile. Whispering gallery mode resonances of the bottle-like microcavity were excited via a tapered fiber at different positions along its axis. A cleaner spectrum with identifiable and traceable features over a broad wavelength range at the center excitation position and the estimated Q factors close to 105 around 1.55 µm are observed. The shifts of resonance frequency by the input light power change demonstrate the potential applications of thermo-optic sensing and frequency tuning.

The hsa_circ_0082152 maintains NF-κB mRNA stability by binding to MTDH to promote anti-tuberculosis drug-induced liver injury.

Anti-tuberculosis drug-induced liver injury (ADLI) is a common adverse reaction during anti-tuberculosis treatment and often leads to treatment interruptions. Circular RNAs (circRNAs) have been identified as key modulators in liver diseases. CircRNAs is a special class of noncoding RNAs that have been found to have significant impacts on the progression of inflammation via various mechanisms. In the serum of ADLI patients, upregulation of the circular RNA hsa_circ_0082152 (derived from the host gene snd1) was observed, along with increased ALT and AST levels, as well as alterations in the levels of inflammation-related factors such as NF-κB, IL-1ß and TNF-α. To elucidate the underlying mechanisms, we established an HL-7702-ADLI cell model and confirmed similar upregulation of hsa_circ_0082152. Downregulation of hsa_circ_0082152 significantly inhibited inflammatory injury in ADLI cells, while upregulation had the opposite effect. RNA immunoprecipitation showed that hsa_circ_0082152 functions by interacting with metadherin (MTDH). Our study further verified that the interaction of hsa_circ_0082152 with the MTDH protein binding to NF-κB mRNA to maintain NF-κB mRNA stability, which increases the expression of NF-κB and its targets IL-1ß and TNF-α. Conversely, depletion of MTDH rescued the promotive effect of hsa_circ_0082152 overexpression on ADLI inflammation. Therefore, hsa_circ_0082152 overexpression promotes ADLI progression via the MTDH/NF-κB axis.

MicroRNA-124 reduces caveolar density by targeting caveolin-1 in porcine kidney epithelial PK15 cells.

Caveolin-1 is the principal component of caveolae, and it is implicated in endocytosis, cholesterol homeostasis, signal transduction and tumorigenesis. MicroRNAs play key regulatory roles in many cellular processes. However, the molecular mechanism by which porcine caveolin-1 is regulated by microRNAs remains unclear. In the present study, we found that miR-124 could directly target caveolin-1 in porcine kidney epithelial cells (PK15). A luciferase reporter assay revealed that miR-124 directly bound to Cav1 mRNA. Ectopic expression of miR-124 decreased porcine Cav1 expression at both the mRNA and protein levels. Furthermore, we used transmission electron microscopy to count caveolae in the cytosolic space next to the membrane and we found that the overexpression of miR-124 in PK15 cells reduced the density of the caveolae. Our results suggested that miR-124 reduced caveolar density by targeting caveolin-1 in PK15 cells; therefore, miR-124 could play an important role in the caveolae-mediated endocytosis of pathogens and signal transduction.

Silencing SIRT1 promotes the anti-HBV action of IFN-α by regulating Pol expression and activating the JAK-STAT signaling pathway.

PURPOSE: The purpose this study is to investigate the impact of SIRT1 on the anti-HBV activity of IFN-α and further elucidate its underlying mechanism. METHODS: HepG2.2.15 cells stably transfected with HBV virus were chosen as the primary study subject. IFN-α was used to stimulate the cells and regulate the expression of SIRT1, and the JAK-STAT pathway and HBV-related indices were measured by qRT-PCR, Western blotting and ELISA. Immunofluorescence (IF) was used to detect the nuclear translocation of STAT1 and STAT2. Coimmunoprecipitation (Co-IP) was used to detect the binding of SIRT1 to HBV Polymerase (Pol). RESULTS: In HepG2.2.15 cells, we found changes in SIRT1 expression. We show that silencing SIRT1 promotes the IFN-α-triggered Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway and consequently enhances the antiviral effects of IFN-α against HBV replication. Importantly, SIRT1 can interact with Pol and increase JAK-STAT activity by regulating Pol expression. Additionally, the inhibition of SIRT1 activity by treatment with the SIRT1 inhibitor selisistat enhanced the anti-HBV effect of IFN-α and JAK-STAT pathway activity. CONCLUSION: In conclusion, our results demonstrate that silencing SIRT1 activates the JAK-STAT pathway and enhances the anti-HBV activity of IFN-α by inhibiting Pol expression. This would be a promising therapeutic target to improve the efficacy of IFN-α in the treatment of CHB.

Stepwise ordering of imidazolium-based cationic surfactants during cooling-induced crystallization.

Surfactants bearing imidazolium cations represent a new class of building blocks in molecular self-assembly. These imidazolium-based cationic surfactants can exhibit various morphologies during phase transformations. In this work, we studied the self-assembly and phase behavior of 1-hexadecyl-3-methylimidazolium chloride (C(16)mimCl) aqueous dispersions (0.5-10 wt %) by using isothermal titration calorimetry, differential scanning calorimetry, synchrotron small- and wide-angle X-ray scattering, freeze-fracture electron microscopy, optical microscopy, electrical conductance, and Fourier transform infrared spectroscopy. It was found that C(16)mimCl in aqueous solutions can form two different crystalline phases. At higher C(16)mimCl concentrations (>6 wt %), the initial spherical micelles convert directly to the stable crystalline phase upon cooling. At lower concentrations (0.5 or 1 wt %), the micelles first convert to a metastable crystalline phase upon cooling and then transform to the stable crystalline phase upon further incubation at low temperature. The electrical conductance measurement reveals that the two crystalline phases have similar surface charge densities and surface curvatures. Besides, the microscopic and spectroscopic investigations of the two crystalline phases suggest that the metastable crystalline phase has preassembled morphology and a preordered submolecular packing state that contribute to the final stable crystalline structure. The formation of a preordered structure prior to the final crystalline state deepens our understanding of the crystallization mechanisms of common surfactants and amphiphilic ionic liquids and should thus be widely recognized and explored.

Hsa_circ_0093884 bound to RNA-binding protein RPS3 ameliorates hepatocyte inflammation in anti-tuberculosis drug-induced liver injury by competitively activating SIRT1.

Anti-tuberculosis drug-induced liver injury (ADLI) is one of the main factors hindering the efficacy of routine chemotherapy against tuberculosis. Understanding the mechanism of ADLI will aid in the effective treatment of patients with tuberculosis. Recently, we found that the expression of hsa_circ_0093884, a circular RNA derived from the NAD-dependent deacetylase, sirtuin-1 (SIRT1), was down-regulated in ADLI. Hsa_circ_0093884 was negatively correlated with the NLR family pyrin domain containing 3 (NLRP3) inflammasome and its overexpression increased the expression levels of NLRP3, interleukin-1ß, and caspase-1. Mechanistically, RNA immunoprecipitation and immunofluorescence assays revealed that the ribosomal protein S3 (RPS3) could bind to hsa_circ_0093884 and SIRT1. Additionally, the expression of hsa_circ_0093884 was positively correlated with that of SIRT1, and the upregulation of hsa_circ_0093884 expression was crucial for the upregulation of SIRT1 expression. We confirmed that the mRNA and protein expression levels of SIRT1 were influenced by hsa_circ_0093884 and RPS3. Furthermore, hsa_circ_0093884 recruited RPS3 to increase SIRT1 mRNA and protein levels. Importantly, we found a marked decrease in the upregulating effect of hsa_circ_0093884 on SIRT1 owing to RPS3 depletion. To the best of our knowledge, this study is the first to reveal that hsa_circ_0093884 regulates SIRT1 expression and inhibits the inflammatory response by binding to RPS3 in ADLI, which may be used to develop novel strategies for ADLI treatment.

Comparative studies on the crystalline to fluid phase transitions of two equimolar cationic/anionic surfactant mixtures containing dodecylsulfonate and dodecylsulfate.

In this work, a cationic surfactant, dodecyltrimethylammonium bromide (DTAB), and an anionic surfactant, sodium dodecylsulfonate (SDSO(3)) or sodium dodecylsulfate (SDSO(4)), were mixed in an equimolar ratio to prepare SDSO(3)-DTAB and SDSO(4)-DTAB binary mixtures. The phase behavior, structure, and morphology of these two surfactant mixtures were investigated by differential scanning calorimetry, synchrotron X-ray scattering, freeze-fracture electron microscopy, and Fourier transform infrared spectroscopy. It was found that upon heating, both of the two systems transform from multilamellar crystalline phase to liquid crystalline (or fluid) phase. It is interesting to find that, although SDSO(3) has a lower molecular weight, the crystalline phase of SDSO(3)-DTAB shows much higher thermostability as compared with that of SDSO(4)-DTAB. Other than this, we observed a large difference in the repeat distances of the two crystalline phases. More interestingly, at 60 °C in the fluid phases, cylindrical micelles formed in the SDSO(3)-DTAB system, while spherical micelles were observed in the SDSO(4)-DTAB system. Our present work demonstrates that a subtle difference in the headgroup structure of the anionic component markedly affects the thermostability, packing structure, and morphology of the surfactant mixtures, which suggests the importance of the match of the head-head and tail-tail interactions between the cationic and anionic surfactants.

Contribution from urban heating to China's 2020 goal of emission reduction.

To reduce inhalable particle and SO(x) pollution from coal-based urban central heating (UCH), China has been vigorously developing natural gas-based UCH for years. The CO(2) emissions of UCH, having an average annual growth rate of 10.3%, accounted for 4.4% of China's total CO(2) emissions in 2009. This paper analyzes the feasibility of replacing UCH with heat pump heating (HPH) in China's climatic suitable regions and evaluates the corresponding potential for energy saving and emission reduction. Current strategy of replacing coal-based UCH with natural gas-based UCH is expected to decrease CO(2) emissions by 63.5%. However, the CO(2) emissions of HPH are 55.4% less than those of natural gas-based UCH. Replacing coal-based UCH with HPH is capable of decreasing CO(2) emissions by 83.7% and consequently decreases the CO(2) emissions per unit of gross domestic product (GDP) by 4.2% by 2020 compared with 2005 level. This contributes about 10.5% to China's 2020 CO(2) emission reduction target. For controlling environmental pollution and protecting ecological environment better, China should adjust its strategy for CO(2) emission reduction by shifting its attention from replacing coal-based UCH with natural gas-based UCH to popularizing HPH in climatic suitable regions.

An Experimental Study on Processing TC4 with Nano Particle Surfactant Mixed Micro EDM.

Micro electrical discharge machining (micro EDM) is able to remove conductive material by non-contact instantaneous high temperature, which is more suitable for machining titanium and its alloys compared with traditional machining methods. To further improve the machining efficiency and machined surface quality of micro EDM, the nano particle surfactant mixed micro EDM method is put forward in this paper. Experiments were conducted to explore the effect of nano particle surfactant on the micro EDM performance of titanium alloy. The results show that the material removal rate of micro EDM in dielectric mixed with TiO2 is the highest when open-circuit voltage is 100 V, followed by Al2O3 and ZrO2. Lower tool wear rate can be produced by using dielectric mixed with nano particle surfactant. The taper ratio of micro EDM in dielectric mixed with nano particle surfactant is higher than that in deionized water. The surface roughness Ra of micro EDM in dielectric mixed with TiO2 can be 50% lower than that in deionized water. It is helpful to improve the machining performance by adding surface surfactant in the dielectric of micro EDM.