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1.
Int J Cancer ; 146(2): 400-412, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31271662

RESUMO

Histone demethylases are promising therapeutic targets as they play fundamental roles for survival of Mixed lineage leukemia rearranged acute leukemia (MLLr AL). Here we focused on the catalytic Jumonji domain of histone H3 lysine 9 (H3K9) demethylase JMJD1C to screen for potential small molecular modulators from 149,519 natural products and 33,765 Chinese medicine components via virtual screening. JMJD1C Jumonji domain inhibitor 4 (JDI-4) and JDI-12 that share a common structural backbone were detected within the top 15 compounds. Surface plasmon resonance analysis showed that JDI-4 and JDI-12 bind to JMJD1C and its family homolog KDM3B with modest affinity. In vitro demethylation assays showed that JDI-4 can reverse the H3K9 demethylation conferred by KDM3B. In vivo demethylation assays indicated that JDI-4 and JDI-12 could induce the global increase of H3K9 methylation. Cell proliferation and colony formation assays documented that JDI-4 and JDI-12 kill MLLr AL and other malignant hematopoietic cells, but not leukemia cells resistant to JMJD1C depletion or cord blood cells. Furthermore, JDI-16, among multiple compounds structurally akin to JDI-4/JDI-12, exhibits superior killing activities against malignant hematopoietic cells compared to JDI-4/JDI-12. Mechanistically, JDI-16 not only induces apoptosis but also differentiation of MLLr AL cells. RNA sequencing and quantitative PCR showed that JDI-16 induced gene expression associated with cell metabolism; targeted metabolomics revealed that JDI-16 downregulates lactic acids, NADP+ and other metabolites. Moreover, JDI-16 collaborates with all-trans retinoic acid to repress MLLr AML cells. In summary, we identified bona fide JMJD1C inhibitors that induce preferential death of MLLr AL cells.

2.
Protein Cell ; 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31758528

RESUMO

Type VII secretion systems (T7SSs) are found in many disease related bacteria including Mycobacterium tuberculosis (Mtb). ESX-1 [early secreted antigen 6 kilodaltons (ESAT-6) system 1] is one of the five subtypes (ESX-1~5) of T7SSs in Mtb, where it delivers virulence factors into host macrophages during infection. However, little is known about the molecular details as to how this occurs. Here, we provide high-resolution crystal structures of the C-terminal ATPase3 domains of EccC subunits from four different Mtb T7SS subtypes. These structures adopt a classic RecA-like ɑ/ß fold with a conserved Mg-ATP binding site. The structure of EccCb1 in complex with the C-terminal peptide of EsxB identifies the location of substrate recognition site and shows how the specific signaling module "LxxxMxF" for Mtb ESX-1 binds to this site resulting in a translation of the bulge loop. A comparison of all the ATPase3 structures shows there are significant differences in the shape and composition of the signal recognition pockets across the family, suggesting that distinct signaling sequences of substrates are required to be specifically recognized by different T7SSs. A hexameric model of the EccC-ATPase3 is proposed and shows the recognition pocket is located near the central substrate translocation channel. The diameter of the channel is ~25-Å, with a size that would allow helix-bundle shaped substrate proteins to bind and pass through. Thus, our work provides new molecular insights into substrate recognition for Mtb T7SS subtypes and also a possible transportation mechanism for substrate and/or virulence factor secretion.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31752150

RESUMO

Objective: To describe the prevalence of metabolic syndrome (MetS) in adolescents and its association with several MetS-related biochemical markers. Methods: A cross-sectional analysis was carried out and data were extracted from the Nutrition and Health Surveillance in Primary and Secondary school students of Beijing (NHSPSB) 2017. Participants were aged 10-15 years old. MetS was diagnosed using the recommended criteria for Chinese adolescents. The associations among MetS, biochemical biomarkers, and socioeconomic status were estimated by multivariable linear regression. Results: The prevalence of MetS in adolescents in Beijing was 3% in the total sample, 4% in boys, and 2% in girls. Moreover, the prevalence of MetS in the overweight and obesity populations were 5% and 12% respectively. The prevalence of MetS remained higher in boys than in girls. The concentrations of alanine aminotransferase (ALT), serum uric acid (SUA), low density lipoprotein (LDL), and C-reactive protein (CRP) were higher in the MetS children in comparison with non-MetS children (All p < 0.05), while the high-density lipoprotein (HDL) concentration was lower in MetS children. After adjusting for socioeconomic parameters in the multivariable regression model, MetS was strongly associated with ALT, SUA, HDL, and LDL. The five components of MetS indicated that abdominal obesity and a high serum triglyceride (TG) concentration were tightly linked with ALT, SUA, LDL, and CRP; while a low HDL concentration and elevated blood pressure were related to enhanced ALT, UA, and CRP. Additionally, impaired fasting glucose was only related to increased ALT. Conclusion: The epidemiological issues of MetS in Beijing adolescents should be known across socioeconomic classes. Early intervention strategies, such as dietary pattern interventions and physical excise, should be designed for that population to reduce the disease burdens of cardiovascular disease (CVD), Type 2 diabetes (T2D), and steatohepatitis in adulthood.

4.
J Chem Phys ; 151(16): 164121, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31675873

RESUMO

Equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) is a reliable and popular approach to the determination of electronic excitation energies. Recently, we have developed a rank-reduced CCSD (RR-CCSD) method that allows the ground-state coupled-cluster energy to be determined with low-rank cluster amplitudes. Here, we extend this approach to excited-state energies through a RR-EOM-CCSD method. We start from the EOM-CCSD energy functional and insert low-rank approximations to the doubles amplitudes. The result is an approximate EOM-CCSD method with only a quadratic number (in the molecular size) of free parameters in the wavefunction. Importantly, our formulation of RR-EOM-CCSD preserves the size intensivity of the excitation energy and size extensivity of the total energy. Numerical tests of the method suggest that accuracy on the order of 0.05-0.01 eV in the excitation energy is possible with 1% or less of the original number of wavefunction coefficients; accuracy of better than 0.01 eV can be achieved with about 4% or less of the free parameters. The amount of compression at a given accuracy level is expected to increase with the size of the molecule. The RR-EOM-CCSD method is a new path toward the efficient determination of accurate electronic excitation energies.

5.
Wei Sheng Yan Jiu ; 48(4): 640-650, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601349

RESUMO

OBJECTIVE: A method for the simultaneous determination of 5 kinds of fish anesthetics residues in fish has been developed by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). Eugenol, methyl-eugenol, methyl-isoeugenol, acetyl-isoeugenol and tricaine methanesulfonate(MS-222) were concerned. METHODS: After homogenization fish samples were extracted by acetonitrile-water(80↿0, V/V), purified by Oasis PRiME HLB solid-phase extraction column. Then after centrifuged and concentrated, the samples were separated by Waters ACQUITY UPLC BEH Phenyl column(2. 1 mm×100 mm, 1. 7 µm). The detection was confirmed and quantified by mass spectrum of triple quadrupole in the multiple reaction monitoring(MRM) mode. RESULTS: The calibration curves showed good linearity in each range with correlation coefficients greater than 0. 995. Three levels spiked recovery experiments were carried out using blank fish mud extraction as substrate, the recoveries ranged from 72. 6% to 106. 0%, the relative standard deviations(RSDs) ranged from 2. 2% to 20. 1%(n=6). The qualitative limits of detections(S/N>3) were 0. 14-0. 30 µg/kg and the quantitative limits(S/N>10) were 0. 5-1. 0 µg/kg. CONSLUSION: The method is simple and easy to operate, with less organic reagent, high sensitivity and good stability. The isomers of methyl eugenol and methyl isoeugenol were successfully separated. It is suitable for the detection of 5 kinds of fish anesthetics in fish.


Assuntos
Anestésicos/metabolismo , Peixes , Espectrometria de Massas em Tandem , Anestésicos/química , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Alimentos Marinhos
6.
Chemistry ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31568591

RESUMO

A new supramolecular nanocage, VMOP-31, based on polyoxovanadate as the molecular building block, has been designed and synthesized under solvothermal conditions. The structure of VMOP-31 was determined by single-crystal and powder X-ray diffraction, FTIR spectroscopy, UV/Vis spectrophotometry, and thermogravimetric analysis. The nanocage exhibits octahedral geometry and is constructed of six {V5 O9 Cl(COO)4 } at the vertices and eight TATB (H3 TATB=4,4',4''-(s-triazine-2,4,6-triyl)tribenzoic acid) ligands on the faces. Impressively, VMOP-31 exhibited high efficiency in the inhibition of cell growth of solid tumors, such as human liver cancer cells SMMC-7721, and superior results in the treatment of liver tumors in mice compared with classic cisplatin. Detailed studies revealed that the potential mechanism of cell death induced by VMOP-31 involves cell cycle arrests, DNA damage, and subsequent apoptosis. Moreover, VMOP-31 exhibited negligible side effects in the mice compared with cisplatin. To the best of our knowledge, VMOP-31 is the first supramolecular nanocage applied to hepatic tumors both in vitro and in vivo.

7.
BMC Infect Dis ; 19(1): 910, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664944

RESUMO

BACKGROUND: On September 4, 2018, a boarding school in the Shunyi District of Beijing, China reported an outbreak of acute gastroenteritis. At least 209 suspected students caused of diarrhea and vomiting. The case was investigated, and control measures were taken to prevent further spread. METHODS: A retrospective cohort study was conducted among the school students and staff in order to test hypothesis that high risk of food served at the school canteen. We collected information on demographics, refectory records, person to person transmission by uniform epidemiological questionnaire. Risk ratios (RR) and 95% confidence intervals (CI) were calculated. Stool specimens of cases and canteen employees, retained food, water, and environmental swabs were investigated by laboratory analysis. RESULTS: We identified 209 cases (including 28 laboratory-confirmed cases) which occurred from August 29 to September 10. All cases were students, and the average age was 20, 52% were male. The outbreak lasted for 13 days, and peaked on September 5. Consumption of Drinks stall and Rice flour stall on September 1 (RR:3.4, 95%CI:1.5-7.8, and RR:7.6, 95%CI:2.8-20.2), Rice flour stall and Fish meal stall on September 2 (RR:4.0, 95%CI:1.2-13.6, and RR:4.6, 95%CI:1.7-12.5), muslim meal stall on September 4 (RR:2.7, 95%CI:1.3-5.4), Barbeque stall on September 5 (RR:3.0, 95%CI:1.2-7.0) were independently associated with increased risk of disease within the following 2 days. Among 35 specimens of rectal swabs or feces from students, 28 specimens were positive. Norovirus GI.6 alone was detected in 23 specimens, Bacillus cereus alone in 3 specimens and both norovirus GI.6 and Bacillus cereus in 2 specimens. Ten specimens of rectal swabs from canteen employees were positive for norovirus GI, and 2 specimens were positive for Bacillus cereus. Four retained food specimens were positive for Bacillus cereus, and environmental samples were negative for any viruses or bacteria. CONCLUSION: Our investigation indicated that canteen employees were infected by two pathogens (norovirus and Bacillus cereus) and transmission may have been possible due to unhygienic practices. Student consumption of food or drink at high-risk stalls was determined as the probable cause of the outbreak.

8.
Inorg Chem ; 58(20): 14159-14166, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31596576

RESUMO

Triplet U@C1(28324)-C80, violating the isolated pentagon rule, is experimentally recognized as the stable isomer for uranium-based endohedral monometallofullerene U@C80. Here we first verified that triplet U@D3(31921)-C80, following the isolated pentagon rule, was to be another thermodynamically stable isomer via density functional theory in conjunction with statistical thermodynamic analysis. U@D3(31921)-C80 was probably missing in the previous experiment and would be a promising isomer in the to-be experiment because of its excellently thermodynamic stability. In addition, the anomalous metal position was revealed in U@D3(31921)-C80 and U@C1(28324)-C80. Four-electron transfer from U to C80 was also revealed for the two isomers. Thus, two unpaired 5f electrons were still in the U for U@D3(31921)-C80 and U@C1(28324)-C80. Moreover, the covalent interactions between U and C80 in U@D3(31921)-C80 were stronger than those in U@C1(28324)-C80. The electrostatic interactions preponderated in the interaction energy ΔEint between U and C80 for U@C1(28324)-C80, and the orbital interactions dominated in the ΔEint for U@D3(31921)-C80. The electrophilic and nucleophilic reactivities were also analyzed for U@D3(31921)-C80 and U@C1(28324)-C80. Electronic circular dichroism spectra were simulated to distinguish the two enantiomers of U@C1(28324)-C80. We are hopeful that this investigation will be valuable for further identification of the two enantiomers in future experiments.

10.
Environ Pollut ; 255(Pt 1): 113122, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520900

RESUMO

Microplastics (MPs) are highly concerned environmental pollutants that are ubiquitous in the environmental and might affect human and animal health. In this study, we exposed pregnant mice to 0.5 and 5 µm with 100 and 1000 µg/L polystyrene MPs, then investigated maternal MPs exposure during gestation and evaluated the potential effects on the mice offspring (PND42). In the F1 offspring, the serum triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels and hepatic TC, TG levels were altered, while some of them were only significant in 5 µm MPs-treated group. Various serum metabolites including amino acids and acyl-carnitines were carried out by nonderivatized tandem mass spectrometry, there were 11 and 15 kinds of metabolites changes significantly in 0.5 and 5 µm MPs-treated groups, respectively. Furthermore, the changes of C0 and C0/(C16 + 18) indicators suggested the potential risk of fatty acid metabolism disorder, which was verified by hepatic genes expression. These results indicated that maternal exposure of two different sizes of polystyrene MPs increased risks of metabolic disorder in their offspring, and greater effects were observed in 5 µm MPs-treated groups. The data provides a preliminary exploration of the potential relationship between MPs and the risk metabolic disorder even in the next generation, which might offer new insights into the health risk assessment of MPs.

11.
Chem Res Toxicol ; 32(10): 2086-2094, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31476867

RESUMO

N6-Formyl-lysine (FLys) is an abundant and lasting protein adduct formed when formaldehyde generated by nitrosative/oxidative stress and inflammation reacts with lysine residues. It is believed that the post-translational N6-formylation of lysine is associated with a variety of pathological processes and human diseases. Thus, FLys may serve well as a dosimetric biomarker for exposure to formaldehyde and other oxidative stress-inducing toxicants. However, since current methods for FLys determination are tedious and time-consuming, we developed and validated an aqueous normal phase liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with isotope-dilution method for the rigorous quantification of FLys with enhanced sensitivity and selectivity. After validating the accuracy and precision of the method with a synthetic peptide containing FLys, the method was applied to quantitate the concentration-dependent formation of FLys in cells exposed to formaldehyde and Fe2+-EDTA, an OH radical-mediated oxidant. The study reveals formaldehyde and Fe2+-EDTA produced FLys at a frequency of 20.2 and 4.1 per 104 lysine per mM, respectively, after correcting for losses during protein digestion steps. The study was further extended to quantitate the concentration-dependent formation of FLys in aristolochic acid I (AA-I) exposed Escherichia coli cells and rat tissues. This study demonstrates for the first time that AA-I exposure induces time- and dose-dependent formation of FLys in cellular proteins. Furthermore, results show AA-I exposure leads to organotropic N6-formylation of lysine, with elevated levels of FLys detectable in the kidney, which is the one of the tumor targeting organs of AAs. Previous studies have also revealed AA exposure induced renal interstitial fibrosis in both laboratory rodents and humans, by a yet to be determined molecular mechanism. These data shed light on the potential caustative role of N6-formylation in the pathophysiology of AA nephrotoxicity and carcinogenicity.

12.
Am J Physiol Regul Integr Comp Physiol ; 317(5): R696-R708, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31508994

RESUMO

The plateau zokor (Eospalax baileyi) is a species of subterranean rodent endemic to the Tibetan Plateau. It is well adapted to the cold and hypoxic and hypercapnic burrow. To study the oxygenation properties of plateau zokor hemoglobins (Hbs), we measured intrinsic Hb-O2 affinities and their sensitivities to pH (Bohr effect); CO2; Cl-, 2,3-diphosphoglycerate (DPG); and temperature using purified Hbs from zokor and mouse. The optimal deoxyHb model of plateau zokor was constructed and used to study its structural characteristics by molecular dynamics simulations. O2 binding results revealed that plateau zokor Hbs exhibit remarkably high intrinsic Hb-O2 affinity, low CO2 effects compared with human and the relatively low anion allosteric effector sensitivities (DPG and Cl-) at normal temperature, which would safeguard the pulmonary Hb-O2 loading under hypoxic and hypercapnic conditions. Furthermore, the high anion allosteric effector sensitivities at low temperature and low temperature sensitivities of plateau zokor Hbs would facilitate the releasing of O2 in cold extremities and metabolic tissues. However, the high Hb-O2 affinity of plateau zokor is not compensated by high pH sensitivity as the Bohr factors of plateau zokor Hbs were as low as those of mouse. The results of molecular dynamics simulations revealed the reduced hydrogen bonding between the α1ß1- and α2ß2-dimer interface of deoxyHb in zokor compared with mouse. It may be the primary mechanism of the high intrinsic Hb-O2 affinities in zokor. Specifically, substitution of the 131Ser→Asn in the α2-chain weakened the connection between α1- and ß2-subunit.

13.
J Comput Chem ; 40(31): 2730-2738, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31433074

RESUMO

The thermodynamic and dynamic stabilities of Sc3 X@C80 (X = C, N, and O) are explored via density functional theory combined with statistical thermodynamic analysis and ab initio molecular dynamics. It is the first time to comprehensively consider the effect of nonmetal atoms on trimetallic endohedral clusterfullerenes. Relative to Sc3 X@Ih (31924)-C80 (X = N and O) with general six-electron transfer, an intriguing electronic structure of unexplored Sc3 C@D5h (31923)-C80 with thermodynamic and dynamic stabilities is clearly disclosed. Natural bond orbitals and charge decomposition analysis simultaneously suggest that one unpaired electron appears on the cage for neutral Sc3 C@D5h (31923)-C80 , which could be prospectively stabilized by effective exohedral derivatization and ionization in the future. Moreover, isoelectronic endohedral clusterfullerenes, (Sc3 C@C80 )- , Sc3 N@C80 , and (Sc3 O@C80 )+ , are also uniquely taken into account. The geometries, electronic structures, reactivities, and reactive sites of isoelectronic species are examined, and it turns out that all the three isoelectronic species would rather electrophilic than nucleophilic reactions. © 2019 Wiley Periodicals, Inc.

14.
Angew Chem Int Ed Engl ; 58(40): 14224-14228, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31389144

RESUMO

The targeted delivery of chemotherapeutic drugs is a major challenge in the clinical treatment of cancer. Herein, we constructed a multifunctional DNA nanoplatform as a versatile carrier of the highly potent platinum-based DNA intercalator, 56MESS. In our rational design, 56MESS was efficiently loaded into the double-bundle DNA tetrahedron through intercalation with the DNA duplex. With the integration of a nanobody that both targets and blocks epidermal growth factor receptor (EGFR), the DNA nanocarriers exhibit excellent selectivity for cells with elevated EGFR expression (a common biomarker related to tumor formation) and combined tumor therapy without obvious systemic toxicity. This DNA-based platinum-drug delivery system provides a promising strategy for the treatment of tumors.

15.
Inorg Chem ; 58(16): 10769-10777, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31385498

RESUMO

Mixed-metal uranium-based endohedral clusterfullerenes, Sc2UX@C80 (X = C, N), which were recently reported in experiments, have been investigated considering heptagon-containing isomers by density functional theory calculations in conjunction with statistical thermodynamic analysis. The triplet Sc2UC@Ih(31924)-C80 and quartet Sc2UN@Ih(31924)-C80, named after the spiral number (31924), are found to be thermodynamically stable and satisfy aromaticity rules. Furthermore, the restricted movements of the Sc2UX (X = C, N) cluster in Ih(31924)-C80 have been demonstrated via ab initio molecular dynamics simulations. The six-electron transfer from the inner cluster to the cage results in the electronic structures (Sc2UX)6+@C806- (X = C, N), which were also confirmed by natural bond orbital analysis. On the basis of the frontier molecular orbitals, the oxidation states of uranium in Sc2UC@C80 and Sc2UN@C80 are +IV and +III, respectively, with residual electrons in 5f orbitals of U. The chemical bond between U and C (N) of the inner cluster is characterized as a double bond (single bond) by an analysis of the Mayer bond orders. There are covalent interactions between the inner cluster and outer cage, which is clarified by the quantum theory of atoms in molecules. IR spectra of the optimal isomers have also been simulated, which show the clear difference between Sc2UX@C80 (X = C, N). These findings, together with simulated results, are expected to supply useful information in future experiments of mixed-metal uranium-based endohedral clusterfullerenes.

16.
Chem Res Toxicol ; 32(8): 1469-1486, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31353895

RESUMO

Cisplatin is one of the most widely used chemotherapeutic agents for various solid tumors in the clinic due to its high efficacy and broad spectrum. The antineoplastic activity of cisplatin is mainly due to its ability to cross-link with DNA, thus blocking transcription and replication. Unfortunately, the clinical use of cisplatin is limited by its severe, dose-dependent toxic side effects. There are approximately 40 specific toxicities of cisplatin, among which nephrotoxicity is the most common one. Other common side effects include ototoxicity, neurotoxicity, gastrointestinal toxicity, hematological toxicity, cardiotoxicity, and hepatotoxicity. These side effects together reduce the life quality of patients and require lowering the dosage of the drug, even stopping administration, thus weakening the treatment effect. Few effective measures exist clinically against these side effects because the exact mechanisms of various side effects from cisplatin remain still unclear. Therefore, substantial effort has been made to explore the complicated biochemical processes involved in the toxicology of cisplatin, aiming to identify effective ways to reduce or eradicate its toxicity. This review summarizes and reviews the updated advances in the toxicological research of cisplatin. We anticipate to provide insights into the understanding of the mechanisms underlying the side effects of cisplatin and designing comprehensive therapeutic strategies involving cisplatin.

17.
Gene ; 717: 143987, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31362037

RESUMO

To improve the accuracy and genetic progress of blue fox breeding, the relationships between genetic polymorphisms and growth and reproductive traits of the blue fox were investigated. MC4R, MC3R, INHA and INHBA were selected as candidate genes for molecular evolution and statistical analyses. Single-factor variance analyses showed that the MC4R (g.267C > T, g.423C > T, and g.731C > A) and MC3R (g.677C > T) genotypes had significant impacts on body weight, chest circumference, abdominal perimeter and body mass index (BMI) (P < 0.05) in blue fox. The MC4R and MC3R combined genotypes had significant effects on the body weight and abdominal circumference. The different genotypes of INHA g.75G > A had significant effects on female fecundity, whereas the different genotypes of INHBA g.404G > T and g.467G > T and the INHA and INHBA combined genotypes had significant effects on male fecundity. The proteins encoded by the open reading frames (ORFs) of different polymorphic loci were predicted and analysed. The aims of this study were to identify genetic markers related to growth and reproduction in the blue fox and to provide an efficient, economical and accurate theoretical approach for auxiliary fox breeding.


Assuntos
Raposas/crescimento & desenvolvimento , Raposas/genética , Polimorfismo de Nucleotídeo Único , Reprodução/genética , Animais , Tamanho Corporal/genética , Peso Corporal/genética , China , Evolução Molecular , Feminino , Raposas/fisiologia , Marcadores Genéticos , Subunidades beta de Inibinas/química , Subunidades beta de Inibinas/genética , Inibinas/química , Inibinas/genética , Desequilíbrio de Ligação , Masculino , Mutação , Receptor Tipo 3 de Melanocortina/química , Receptor Tipo 3 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/química , Receptor Tipo 4 de Melanocortina/genética
18.
Autophagy ; : 1-11, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31241013

RESUMO

SQSTM1/p62 (sequestosome 1) is a critical macroautophagy/autophagy receptor that promotes the formation and degradation of ubiquitinated aggregates. SQSTM1 can be modified by ubiquitination, and this modification modulates its autophagic activity. However, the molecular mechanisms underpinning its reversible deubiquitination have never been described. Here we report that USP8 (ubiquitin specific peptidase 8) directly interacted with and deubiquitinated SQSTM1. USP8 preferentially removed the lysine 11 (K11)-linked ubiquitin chains from SQSTM1. Moreover, USP8 deubiquitinated SQSTM1 principally at K420 within its ubiquitin-association (UBA) domain. Finally, USP8 inhibited SQSTM1 degradation and autophagic influx in cells with wild-type SQSTM1, but not its mutant with substitution of K420 with an arginine. Taken together, USP8 acts as a negative regulator of autophagy by deubiquitinating SQSTM1 at K420. Abbreviations: BafA1: bafilomycin A1; BAP1: BRCA1 associated protein 1; DUB: deubiquitinating enzyme; ESCRT: endosomal sorting complex required for transport; HTT: huntingtin; K: lysine; KEAP1: kelch like ECH associated protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MEF: mouse embryonic fibroblast; shRNA: short hairpin RNA; SQSTM1: sequestosome 1; Ub: ubiquitin; UBA: ubiquitin-association; UBE2D2: ubiquitin conjugating enzyme E2 D2; UBE2D3: ubiquitin conjugating enzyme E2 D3; USP: ubiquitin specific peptidase; WT: wild-type.

19.
Insect Sci ; 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31215133

RESUMO

Hylyphantes graminicola is a resident spider species found in maize and cotton fields and is an important biological control agent of various pests. Previous studies have demonstrated that stress from elevated CO2 and Wolbachia infection can strongly affect spider species. Thus, based on CO2 levels (400 ppm, current atmospheric CO2 concentration and 800 ppm, high CO2 concentration) and Wolbachia status (Wolbachia-infected, W+ and Wolbachia-uninfected, W- ), we divided H. graminicola individuals into four treatment groups: W- 400 ppm, W- 800 ppm, W+ 400 ppm, and W+ 800 ppm. To investigate the effects of elevated CO2 levels (W- 400 vs W- 800), Wolbachia infection (W- 400 vs W+ 400), and the interactions between these two factors (W- 400 vs W+ 800), high-throughput transcriptome sequencing was employed to characterize the de novo transcriptome of the spiders and identify stress-related differentially expressed genes (DEGs). De novo assembly of complementary DNA sequences generated 86 688 unigenes, 23 938 of which were annotated in public databases. A total of 84, 21, and 157 DEGs were found among W- 400 vs W- 800, W- 400 vs W+ 400, and W- 400 vs W+ 800, respectively. Functional enrichment analysis revealed that metabolic processes, signaling, and catalytic activity were significantly affected by elevated CO2 levels and Wolbachia infection. Our findings suggest that the impact of elevated CO2 levels and Wolbachia infection on the H. graminicola transcriptome was, to a large extent, on genes involved in metabolic processes. This study is the first description of transcriptome changes in response to elevated CO2 levels and Wolbachia infection in spiders.

20.
Chemosphere ; 234: 204-214, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31220654

RESUMO

In drinking water treatment, complete mineralization of organophosphorus pesticides (OPPs) by UV-based advanced oxidation processes (UV AOPs) is rarely achieved. The formation of intermediate oxidation byproducts would likely have some profound effects on toxicity of the reaction solutions. This study investigated the intermediate oxidation byproducts, transformation pathway and toxicity of malathion solutions during the treatment processes of UV alone, UV/H2O2, UV/TiO2 and UV/Fenton. The main intermediate oxidation byproducts were derived using ultra-performance liquid chromatography - electrospray - time-of-flight mass spectrometry. Thereby the transformation pathway for each of these treatment processes was proposed. The results indicate that in UV photolysis, the transformation pathway of malathion proceeded initially via cleavage of the phosphorus-sulfur bonds while in photocatalysis, the desulfurization from a PS bond to a PO bond was the primary degradation pathway. Interestingly, only in the UV/TiO2 process a small fraction of malathion was found decomposed via a demethylation reaction. At the same time, a toxicity assessment of the treated solutions was conducted by both luminescence inhibition of Vibrio fischeri and inhibition of acetylcholinesterase (AChE). It was found that after UV AOP treatment, the toxicity of the malathion aqueous solution increased sharply. In contrast, no increase in toxicity was observed for the malathion aqueous solution after UV alone treatment. This study demonstrates that the high removal efficiency achieved by OPPs does not imply that detoxification of the water solution has been achieved. On the contrary, the toxicity of the treated solutions by OPPs may be increased significantly depending on the selected treatment processes.


Assuntos
Aliivibrio fischeri/crescimento & desenvolvimento , Inseticidas/toxicidade , Malation/toxicidade , Fotólise , Raios Ultravioleta , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos , Aliivibrio fischeri/efeitos dos fármacos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/efeitos da radiação , Ferro/química , Ferro/efeitos da radiação , Oxirredução , Titânio/química , Titânio/efeitos da radiação , Poluentes Químicos da Água/química
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