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1.
Int J Biol Macromol ; : 134446, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39098696

RESUMEN

Glycoside hydrolase family 91 (GH91) inulin fructotransferase (IFTases) enables biotransformation of fructans into sugar substitutes for dietary intervention in metabolic syndrome. However, the catalytic mechanism underlying the sequential biodegradation of inulin remains unelusive during the biotranformation of fructans. Herein we present the crystal structures of IFTase from Arthrobacter aurescens SK 8.001 in apo form and in complexes with kestose, nystose, or fructosyl nystose, respectively. Two kinds of conserved noncatalytic binding regions are first identified for IFTase-inulin interactions. The conserved interactions of substrates were revealed in the catalytic center that only contained a catalytic residue E205. A switching scaffold was comprised of D194 and Q217 in the catalytic channel, which served as the catalytic transition stabilizer through side chain displacement in the cycling of substrate sliding in/out the catalytic pocket. Such features in GH91 contribute to the catalytic model for consecutive cutting of substrate chain as well as product release in IFTase, and thus might be extended to other exo-active enzymes with an enclosed bottom of catalytic pocket. The study expands the current general catalytic principle in enzyme-substrate complexes and shed light on the rational design of IFTase for fructan biotransformation.

2.
J Immunol ; 213(5): 743-752, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39058321

RESUMEN

IFN regulatory factors (IRFs) are transcription factors that mediate homeostatic mechanisms of host defense against pathogens. In addition to IRF1-9, which are conserved across vertebrates, teleost fishes have two other IRFs, IRF10 and IRF11. In zebrafish (Danio rerio), IRF10 represses the expression of IFNφ1 and IFNφ3, whereas IRF11 exerts the opposite effect. In this study, we found IRF10 could significantly inhibit the expression of IFNφ1 and IFNφ3 induced by IFN11 to synergistically regulate type I IFN expression. To clarify the synergistically regulatory mechanism of IRF10 and IRF11 in type I IFN expression, we determined and analyzed the crystal structures of the DNA-binding domains (DBDs) of zebrafish IRF10 and IRF11 bound to DNA, as well as IRF11 DBD in apo form. The interactions of IRF10-DBD and IRF11-DBD with DNA backbone were elaborated in detail. Further analysis showed that IRF10 and IRF11 have the same binding patterns and comparable affinities with the IFN-sensitive response elements of IFNφ1 and IFNφ3 promoters. Therefore, IRF10 could function as a controlling factor for IRF11 by competitive binding of the IFN-sensitive response elements to coregulate the host IFN response. Accordingly, similar to IRF1 and IRF2 in mammals, IRF10 and IRF11 act as another pair of negative and positive regulators to balance the antiviral responses in fish.


Asunto(s)
ADN , Factores Reguladores del Interferón , Pez Cebra , Animales , Pez Cebra/inmunología , ADN/inmunología , Factores Reguladores del Interferón/metabolismo , Factores Reguladores del Interferón/genética , Cristalografía por Rayos X , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Unión Proteica , Regulación de la Expresión Génica , Interferón Tipo I/metabolismo , Interferón Tipo I/inmunología , Interferones/metabolismo , Interferones/inmunología
3.
BMC Med ; 22(1): 27, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38317125

RESUMEN

BACKGROUND: New "noncardiac" problems in children with congenital heart disease (CHD), such as developmental delay or long-term neurodevelopmental impairments, have attracted considerable attention in recent years. It is hypothesized that exercise might attenuate CHD-associated neurodevelopmental impairments; however, this has not been thoroughly investigated. The objective of this prospective, single-blinded, randomized controlled experiment was to evaluate the impact of customized home-based exercise for children with CHD. METHODS: Children aged 0-5 years with echocardiography-confirmed simple CHD subtypes who were scheduled to undergo cardiac catheterization were screened for enrolment. Among 420 screened CHD children, 192 were enrolled and randomly assigned at a 1:1 ratio to receive a 6-month intervention (30 min daily customized home-based exercise program with supervision for no less than 5 days per week, combined with home-based exercise education) or control treatment (home-based education). The primary outcome was motor development (gross motor quotient (GMQ), fine motor quotient (FMQ), and total motor quotient (TMQ)). The secondary outcomes were cardiac function and structure, bone quality, physical development, parental anxiety, caregiver burden, and quality of life. Children and their families were assessed before and 1, 3, and 6 months after catheterization; 183 (95.3%) children were included in the primary analysis. RESULTS: After 6-month treatment, the intervention group significantly increased their motor quotient, which was consistently higher than that of the control group (GMQ p < 0.0001, FMQ p = 0.02, TMQ p < 0.001). The physical developments in height, weight, and circumferences of the upper-arm, chest, and head were also significantly improved by exercise (all p < 0.017). No significant improvements in the bone strength or the cardiac structure and function were found among patients in the intervention group (all p > 0.017). For parents, higher quality of life level (total score p = 0.016) was observed in the intervention group; while effects of exercise on the anxiety (rude score p = 0.159, standard score p = 0.159) or the Zarit caregiver burden scale score (p = 0.404) were non-significant. No adverse events occurred during the study period. CONCLUSIONS: Customized home-based exercise improved motor development in children with CHD. While the long-term effects of parent training in home-based exercise are unknown, the study results suggest positive outcomes. TRIAL REGISTRATION: A home-based exercise program in congenital heart disease children with cardiac catheterization: a randomized controlled trial. ( http://www.chictr.org.cn/ , ChiCTR-IOR-16007762, January 14, 2016).


Asunto(s)
Cardiopatías Congénitas , Pruebas Psicológicas , Calidad de Vida , Autoinforme , Niño , Humanos , Estudios Prospectivos , Cardiopatías Congénitas/terapia , Padres
4.
Sci Total Environ ; 912: 169210, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38097070

RESUMEN

Constructing hydraulic engineering ensures agricultural development and improves salinization environments. However, in seasonally frozen salinization regions, hydraulic engineering is prone to deformation failure. Leakage from canal raises the regional groundwater level, triggering secondary salinization environmental issues. Exploring the instability mechanisms is thus necessary for hydraulic engineering. Traditional deformation monitoring techniques and soil experiments are constrained by observation scale and timeliness. In this study, Sentinel-1B data from November 2017 to August 2019 were acquired. The small baseline subset (SBAS) InSAR approach was employed to interpret the seasonal deformation characteristics in both the vertical and slope directions of a damaged canal segment in Songyuan, Northeast China. The mechanical properties of saline-alkali soil under varying water contents were quantified by integrating unconfined compression experiment (UCE). In May, as the soil thawed downward, a frozen lenses with poor permeability formed at a depth of approximately 100 cm, causing the accumulation of meltwater and infiltrated precipitation between the frozen layer and the melting layer in the canal. The soil water content at a depth of 80 to 140 cm exceeded 22 %, reaching a threshold for rapid reduction in unconfined compression strength (UCS). Consequently, in spring, the low soil strength between the frozen layer and the melting layer resulted in interface sliding, with a displacement of -133.88 mm in the canal slope direction. Furthermore, the differential projection of freeze-thaw deformation in the slope direction caused continuous creep of the canal towards the free face, with a value of -23.27 mm, exacerbating the formation of the late spring landslide. Integrating InSAR and engineering geological analysis is beneficial for addressing deformation issues in hydraulic engineering. Ensuring the sustainable operation of hydraulic engineering holds important implications for mitigating the salinization process.

5.
Exp Biol Med (Maywood) ; 248(14): 1267-1277, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37728157

RESUMEN

Defects in migration and invasion caused by dysregulation of trophoblast epithelial-mesenchymal transformation (EMT) are one of the key factors in the pathogenesis of preeclampsia (PE). RNA-binding motif protein 25 (RBM25) is an RNA-binding protein involved in a variety of cellular processes, including cell proliferation, apoptosis, cell migration and invasion, and EMT. However, the expression and function of RBM25 in placental of PE remain unclear. In this study, we reveal that the expression of RBM25 is significantly elevated in PE placental tissue. RBM25 depletion and over-expression in trophoblast cells increase and decrease, respectively, cell migration and invasion by regulating EMT marker E-cadherin and Vimentin expression. Mechanistically, Grhl2 is involved in RBM25-regulated trophoblast cell migration, invasion, and EMT through RBM25-facilitated mRNA stabilization. Furthermore, the upregulation of Grhl2 enhances the expression of RBM25 through transcription and forms a positive feedback regulation in the progression of PE. These findings suggest that upregulation of RBM25 induces dysregulation of trophoblast EMT by enhancing positive feedback regulation of Grhl2 and RBM25, leading to defects in cell migration and invasion. Targeting this newly identified regulatory axis may provide benefits in the prevention and treatment of PE.


Asunto(s)
MicroARNs , Preeclampsia , Humanos , Femenino , Embarazo , Trofoblastos/metabolismo , Transición Epitelial-Mesenquimal/genética , Placenta/metabolismo , Preeclampsia/patología , Retroalimentación , Proliferación Celular/genética , Movimiento Celular/genética , MicroARNs/genética
6.
BMC Pregnancy Childbirth ; 23(1): 615, 2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37633887

RESUMEN

BACKGROUND: The two-child policy implemented in China resulted in a surge of high-risk pregnancies among advanced maternal aged women and presented a window of opportunity to identify a large number of placenta accreta spectrum (PAS) cases, which often invoke severe blood loss and hysterectomy. We thus had an opportunity to evaluate the surgical outcomes of a unique conservative PAS management strategy for uterus preservation, and the impacts of magnetic resonance imaging (MRI) in PAS surgical planning. METHODS: Cross-sectional study, comparing the outcomes of a new uterine artery ligation combined with clover suturing technique (UAL + CST) with the existing conservative surgical approaches in a maternal public hospital with an annual birth of more than 20,000 neonates among all placenta previa cases suspecting of PAS between January 1, 2015 and December 31, 2018. RESULTS: From a total of 89,397 live births, we identified 210 PAS cases from 400 singleton pregnancies with placenta previa. Aside from 2 self-requested natural births (low-lying placenta), all PAS cases had safe cesarean deliveries without any total hysterectomy. Compared with the existing approaches, the evaluated UAL + CST had a significant reduction in intraoperative blood loss (ß=-312 ml, P < .001), RBC transfusion (ß=-1.08 unit, P = .001), but required more surgery time (ß = 16.43 min, P = .01). MRI-measured placenta thickness, when above 50 mm, can increase blood loss (ß = 315 ml, P = .01), RBC transfusion (ß = 1.28 unit, P = .01), surgery time (ß = 48.84 min, P < .001) and hospital stay (ß = 2.58 day, P < .001). A majority of percreta patients resumed normal menstrual cycle within 12 months with normal menstrual fluid volume, without abnormal urination or defecation. CONCLUSIONS: A conservative surgical management approach of UAL + CST for PAS is safe and effective with a low complication rate. MRI might be useful for planning PAS surgery. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR2000035202.


Asunto(s)
Placenta Accreta , Placenta Previa , Anciano , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Transversales , Placenta Accreta/cirugía , Placenta Previa/cirugía , Estudios Retrospectivos , Útero/diagnóstico por imagen , Útero/cirugía
7.
J Virol ; 97(4): e0182922, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-36943056

RESUMEN

Spring viremia of carp virus (SVCV) is a highly pathogenic Vesiculovirus infecting the common carp, yet neither a vaccine nor effective therapies are available to treat spring viremia of carp (SVC). Like all negative-sense viruses, SVCV contains an RNA genome that is encapsidated by the nucleoprotein (N) in the form of a ribonucleoprotein (RNP) complex, which serves as the template for viral replication and transcription. Here, the three-dimensional (3D) structure of SVCV RNP was resolved through cryo-electron microscopy (cryo-EM) at a resolution of 3.7 Å. RNP assembly was stabilized by N and C loops; RNA was wrapped in the groove between the N and C lobes with 9 nt nucleotide per protomer. Combined with mutational analysis, our results elucidated the mechanism of RNP formation. The RNA binding groove of SVCV N was used as a target for drug virtual screening, and it was found suramin had a good antiviral effect. This study provided insights into RNP assembly, and anti-SVCV drug screening was performed on the basis of this structure, providing a theoretical basis and efficient drug screening method for the prevention and treatment of SVC. IMPORTANCE Aquaculture accounts for about 70% of global aquatic products, and viral diseases severely harm the development of aquaculture industry. Spring viremia of carp virus (SVCV) is the pathogen causing highly contagious spring viremia of carp (SVC) disease in cyprinids, especially common carp (Cyprinus carpio), yet neither a vaccine nor effective therapies are available to treat this disease. In this study, we have elucidated the mechanism of SVCV ribonucleoprotein complex (RNP) formation by resolving the 3D structure of SVCV RNP and screened antiviral drugs based on the structure. It is found that suramin could competitively bind to the RNA binding groove and has good antiviral effects both in vivo and in vitro. Our study provides a template for rational drug discovery efforts to treat and prevent SVCV infections.


Asunto(s)
Modelos Moleculares , Rhabdoviridae , Ribonucleoproteínas , Proteínas Virales , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Rhabdoviridae/química , Rhabdoviridae/efectos de los fármacos , Proteínas Virales/química , Proteínas Virales/metabolismo , Estructura Cuaternaria de Proteína , Antivirales/farmacología , Evaluación Preclínica de Medicamentos , Microscopía por Crioelectrón , Suramina/farmacología
8.
Commun Biol ; 6(1): 156, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-36750726

RESUMEN

Global control of the tuberculosis epidemic is threatened by increasing prevalence of drug resistant M. tuberculosis isolates. Many genome-wide studies focus on SNP-associated drug resistance mechanisms, but drug resistance in 5-30% of M. tuberculosis isolates (varying with antibiotic) appears unrelated to reported SNPs, and alternative drug resistance mechanisms involving variation in gene/protein expression are not well-studied. Here, using an omics approach, we identify 388 genes with lineage-related differential expression and 68 candidate drug resistance-associated gene pairs/clusters in 11 M. tuberculosis isolates (variable lineage/drug resistance profiles). Structural, mutagenesis, biochemical and bioinformatic studies on Rv3094c from the Rv3093c-Rv3095 gene cluster, a gene cluster selected for further investigation as it contains a putative monooxygenase/repressor pair and is associated with ethionamide resistance, provide insights on its involvement in ethionamide sulfoxidation, the initial step in its activation. Analysis of the structure of Rv3094c and its complex with ethionamide and flavin mononucleotide, to the best of our knowledge the first structures of an enzyme involved in ethionamide activation, identify key residues in the flavin mononucleotide and ethionamide binding pockets of Rv3094c, and F221, a gate between flavin mononucleotide and ethionamide allowing their interaction to complete the sulfoxidation reaction. Our work broadens understanding of both lineage- and drug resistance-associated gene/protein expression perturbations and identifies another player in mycobacterial ethionamide metabolism.


Asunto(s)
Antituberculosos , Farmacorresistencia Bacteriana Múltiple , Etionamida , Mycobacterium tuberculosis , Antituberculosos/farmacología , Etionamida/farmacología , Mononucleótido de Flavina , Mycobacterium tuberculosis/genética , Farmacorresistencia Bacteriana Múltiple/genética
9.
J Am Chem Soc ; 144(41): 18834-18843, 2022 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-36201849

RESUMEN

We report a stable, water-soluble, mononuclear manganese(IV) complex [MnIV(H2L)]·5H2O (Mn-HDCL) that acts as an efficient photothermal material. This system is based on a hexahydrazide clathrochelate ligand (L/HDCL) and is obtained via an efficient one-pot templated synthesis that avoids the need for harsh reaction conditions. Scanning tunneling microscopy images reveal that Mn-HDCL exists as a 2D sheet-like structure. In Mn-HDCL, the manganese(IV) ion is trapped within the cavity of the cage-like ligand. This effectively shields the Mn(IV) ion from the external environment while providing adequate water solubility. As a result of orbital transitions involving the coordinated manganese(IV) ion, as well as metal-to-ligand charge transfer effects, Mn-HDCL possesses a large extinction coefficient and displays a photothermal performance comparable to single-wall carbon nanotubes in the solid state. A high photothermal conversion efficiency (ca. 71%) was achieved in aqueous solution when subjected to near-infrared 730 nm laser photo-irradiation. Mn-HDCL is paramagnetic and provides a modest increase in the T1-weighted contrast of magnetic resonance images both in vitro and in vivo. Mn-HDCL was found to target tumors passively and allow tumor margins to be distinguished in vivo in a mouse model. In addition, it also exhibited an efficient laser-triggered photothermal therapy effect in vitro and in vivo. We thus propose that Mn-HDCL could have a role to play as a tumor-targeting photothermal sensitizer.


Asunto(s)
Manganeso , Nanotubos de Carbono , Ratones , Animales , Manganeso/química , Ligandos , Rayos Infrarrojos , Iones , Agua
10.
Biosaf Health ; 4(6): 365-368, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36168401

RESUMEN

The outbreaks of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant in China have revealed a high rate of asymptomatic cases, making isolation and quarantine measures exceedingly difficult. Public health surveillance and intervention measures will require rapid and accurate testing preferably on-site using point-of-care tests (POCTs) technology for SARS-CoV-2 variants. However, delayed and/or inaccurate surveillance data is a major obstacle blocking the large-scale implementation of POCTs in curbing spread of infectious pathogens and reducing mortality during an outbreak. To determine levels of community transmission and timely strategies accordingly, highly sensitive and specific POCT embedded with the internet of things (IoT) technology could enable on-site screening and real-time data collection. A new Rapid Amplification with Sensitivity And Portability point-of-care test (RASAP-POCT) system based on thermal convection PCR is the first IoT-based isothermal nucleic acid amplification POCT, which can provide test results within 20-30 min using saliva and/or nasopharyngeal swab samples without nucleic acid extraction. With the IoT-imbedded feature, the RASAP-POCT system can be integrated easily and smoothly with China's existing mobile-phone-based contact tracing system, which has previously proved to be highly effective in maintaining the dynamic zero-COVID policy. Current regulatory guidelines and rules should be modified to accelerate the adoption of new technologies under an emergency use authorization (EUA).

11.
J Biomed Sci ; 29(1): 58, 2022 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-35964029

RESUMEN

BACKGROUND: Severe cutaneous adverse drug reactions (SCARs) are a group of serious clinical conditions caused by immune reaction to certain drugs. The allelic variance of human leukocyte antigens of HLA-B*13:01 has been strongly associated with hypersensitivities induced by dapsone (DDS). T-cell receptor mediated activation of cytotoxic T lymphocytes (CTLs) has also been suggested to play an essential role in pathogenesis of SCARs. However, HLA-B*13:01-DDS-TCR immune synapse that plays role in drug-induced hypersensitivity syndrome (DIHS) associated T cells activation remains uncharacterized. METHODS: To investigate the molecular mechanisms for HLA-B*13:01 in the pathogenesis of Dapsone-induced drug hypersensitivity (DDS-DIHS), we performed crystallization and expanded drug-specific CTLs to analyze the pathological role of DDS-DIHS. RESULTS: Results showed the crystal structure of HLA-B*13:01-beta-2-microglobulin (ß2M) complex at 1.5 Å resolution and performed mutation assays demonstrating that I118 or I119, and R121 of HLA-B*13:01 were the key residues that mediate the binding of DDS. Subsequent single-cell TCR and RNA sequencing indicated that TCRs composed of paired TRAV12-3/TRBV28 clonotype with shared CDR3 region specifically recognize HLA-B*13:01-DDS complex to trigger inflammatory cytokines associated with DDS-DIHS. CONCLUSION: Our study identified the novel p-i-HLA/TCR as the model of interaction between HLA-B*13:01, DDS and the clonotype-specific TCR in DDS-DIHS.


Asunto(s)
Dapsona , Hipersensibilidad a las Drogas , Cicatriz/inducido químicamente , Cicatriz/complicaciones , Dapsona/efectos adversos , Hipersensibilidad a las Drogas/genética , Antígenos HLA-B/genética , Humanos , Receptores de Antígenos de Linfocitos T , Linfocitos T
12.
Angew Chem Int Ed Engl ; 60(45): 24162-24170, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34278705

RESUMEN

Solid-state electrolytes (SSEs) show potential in addressing the safety issues of liquid batteries, but the poor interface contact between them and the electrodes hinders practical applications. Here, coordination chemistry of nitrile groups based on succinonitrile (SCN) and polyacrylonitrile (PAN) is studied on the surface of Li6.4 La3 Zr1.4 Ta0.6 O12 (LLZTO) SSE to build the chemical bonded electrolyte/electrode interfaces. The coordination of the nitrile group and LLZTO is clarified. A deformable PAN-modifying SCN electrolyte (PSE) interphase with stable ionic conductivity (10-4  S cm-1 ) and high lithium-ion transference number (0.66) is fabricated on the surface of LLZTO electrolyte based on the coordination competition of nitrile groups. Once applied to SSBs, it endows low interface resistance and strong bonding for the electrolyte/electrode interfaces so that the initial Coulomb efficiency reaches 95.6 % and the capacity remains 99 % after 250 cycles at 25 °C.

13.
J Environ Manage ; 295: 113139, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34174684

RESUMEN

Hydrogen bonding interactions among poly vinyl alcohol (PVA), xanthan gum (XG) and acrylic acid (AA) molecules have been utilized to prepare an environment-friendly interpenetrating double-network hydrogel dust suppressant (PVA-XG-PAA/SDBS) with the aim of enhancing the poor mechanical performance of current hydrogel dust suppressants. A single factor test was used to determine the optimal formulation conditions for the PVA-XG-PAA/SDBS, and the viscosity, surface tension, compression strength, wind resistance, water retention and biodegradability of the samples were measured. The results showed that the hydrogel with optimal usage contained 1.5 g, 0.1 g, and 6 g of PVA, XG and AA, respectively and the optimal reaction temperature was 55 °C. Under the optimal conditions, the viscosity was 45 mPa s, the surface tension was 30 mN/m, the compression strength of the dust suppressant-solidified coal pillar reached 126 kPa, and the degradation rate at the 8th cycle (40 days) after being buried in soil was 34%. Compared with a conventional hydrogel dust suppressant, like poly acrylic acid (PAA), and the dust suppressant sodium dodecyl benzene sulfonate (SDBS), the PVA-XG-PAA/SDBS showed better water retention, wind erosion resistance, and dust-solidifying properties. On the basis of these remarkable properties, the PVA-XG-PAA/SDBS is applicable for dust prevention during coal mining, transport, and storage, which enhances the dust suppression efficiency obviously and has significant meaning to the sustainable development of the coal mining industry while protecting the environment.


Asunto(s)
Hidrogeles , Alcohol Polivinílico , Acrilatos , Polvo , Polisacáridos Bacterianos
14.
Adv Sci (Weinh) ; 7(12): 2000871, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32596129

RESUMEN

The Legionella pneumophila effector MavC is a transglutaminase that carries out atypical ubiquitination of the host ubiquitin (Ub)-conjugation enzyme UBE2N by catalyzing the formation of an isopeptide bond between Gln40Ub and Lys92UBE2N, which leads to inhibition of signaling in the NF-κB pathway. In the absence of UBE2N, MavC deamidates Ub at Gln40 or catalyzes self-ubiquitination. However, the mechanisms underlying these enzymatic activities of MavC are poorly understood at the molecular level. This study reports the structure of the MavC-UBE2N-Ub ternary complex representing a snapshot of MavC-catalyzed crosslinking of UBE2N and Ub, which reveals the way by which UBE2N-Ub binds to the Insertion and Tail domains of MavC. Based on the structural and experimental data, the catalytic mechanism for the deamidase and transglutaminase activities of MavC is proposed. Finally, by comparing the structures of MavC and MvcA, the homologous protein that reverses MavC-induced UBE2N ubiquitination, several essential regions and two key residues (Trp255MavC and Phe268MvcA) responsible for their respective enzymatic activities are identified. The results provide insights into the mechanisms for substrate recognition and ubiquitination mediated by MavC as well as explanations for the opposite activity of MavC and MvcA in terms of regulation of UBE2N ubiquitination.

15.
J Virol ; 94(15)2020 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-32434890

RESUMEN

Spring viremia of carp virus (SVCV) is a highly pathogenic Vesiculovirus in the common carp. The phosphoprotein (P protein) of SVCV is a multifunctional protein that acts as a polymerase cofactor and an antagonist of cellular interferon (IFN) response. Here, we report the 1.5-Å-resolution crystal structure of the P protein central domain (PCD) of SVCV (SVCVPCD). The PCD monomer consists of two ß sheets, an α helix, and another two ß sheets. Two PCD monomers pack together through their hydrophobic surfaces to form a dimer. The mutations of residues on the hydrophobic surfaces of PCD disrupt the dimer formation to different degrees and affect the expression of host IFN consistently. Therefore, the oligomeric state formation of the P protein of SVCV is an important mechanism to negatively regulate host IFN response.IMPORTANCE SVCV can cause spring viremia of carp with up to 90% lethality, and it is the homologous virus of the notorious vesicular stomatitis virus (VSV). There are currently no drugs that effectively cure this disease. P proteins of negative-strand RNA viruses (NSVs) play an essential role in many steps during the replication cycle and an additional role in immunosuppression as a cofactor. All P proteins of NSVs are oligomeric, but the studies on the role of this oligomerization mainly focus on the process of virus transcription or replication, and there are few studies on the role of PCD in immunosuppression. Here, we present the crystal structure of SVCVPCD A new mechanism of immune evasion is clarified by exploring the relationship between SVCVPCD and host IFN response from a structural biology point of view. These findings may provide more accurate target sites for drug design against SVCV and provide new insights into the function of NSVPCD.


Asunto(s)
Fosfoproteínas/química , Rhabdoviridae/química , Proteínas Virales/química , Animales , Cristalografía por Rayos X , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta
16.
Vet Immunol Immunopathol ; 221: 110009, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31945652

RESUMEN

A 14-day experiment was conducted to explore the pathological process and immune response of soybean meal (SBM) induced enteritis (SBMIE) in grass carp (Ctenopharyngodon idellus). The complete replacement of dietary fish meal (FM) with SBM resulted in a remarkable reduction in final body weight, weight gain ratio, and feed conversion efficiency (p < 0.05). The typical histopathological changes of SBMIE appeared starting at day 4, and progressively increased in severity until day 8, then gradually subsided after day 11. The course of SBMIE could be divided into incubation period (days 1-2), prodromal period (days 3-6), symptomatic period (days 7-10), and convalescent period (days 11-14). Transcription levels of pro-inflammatory cytokines, including IL-1ß, TNF-α, IL-6, IL-8, IL-17A/F1 and IFN-γ2, were up-regulated during the prodromal period, and then down-regulated during the convalescent period. Transcript levels of anti-inflammatory cytokines (IL-10 and TGFß1) and their receptors (IL-10R1 and TßRII), were up-regulated during the prodromal and convalescent periods. Transcript levels of MHCIIß, Igµ, Igτ, TCRδ, TCRß, CD4, and CD8α were altered in SBMIE. Furthermore, expression levels of T-bet, IFN-γ2, RORγ2 and IL-17A/F1 were significantly increased in the initiation of enteritis, whereas the transcript levels of Foxp3 and IL-2/15Ra were significantly up-regulated in the repair of enteritis. In conclusion, grass carp SBMIE is regulated by the adjustment of SBM-based diet intake, and the changes of the above-mentioned genes expression suggest that these genes may be involved in SBMIE.


Asunto(s)
Alimentación Animal/análisis , Carpas/inmunología , Citocinas/inmunología , Enteritis/veterinaria , Enfermedades de los Peces/inmunología , Tracto Gastrointestinal/inmunología , Glycine max/efectos adversos , Animales , Carpas/metabolismo , Citocinas/genética , Suplementos Dietéticos , Enteritis/inducido químicamente , Enteritis/inmunología , Enfermedades de los Peces/inducido químicamente , Tracto Gastrointestinal/patología , Inflamación/genética , Glycine max/química
17.
RSC Adv ; 10(12): 7004-7010, 2020 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-35493874

RESUMEN

Two new homo chiral Cu-Ln (Ln = Gd and Ho) compounds bearing a chiral Schiff base ligand (1R,3S)-N',N''-bis[3-methoxysalicylidene]-1,3-diamino-1,2,2-trimethylcyclopentane (H2L) have been synthesized and characterized by elemental analysis, IR spectroscopic and single-crystal X-ray diffraction techniques. The compounds were found to exhibit 1D zig-zag skeletons with double µ-1,5 bridging dicyanamide anions. Circular dichroism (CD) spectra have been used to verify their chiroptical activities. Magnetic studies suggest that 1 and 2 hold the same magnetic behavior with the dinuclear compounds presenting ferromagnetic interaction. Furthermore, both compounds show ferroelectricity with the remnant polarization (P r) value of 0.23 and 0.18 µC cm-2 at room temperature, respectively.

18.
Fish Shellfish Immunol ; 97: 523-530, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31881328

RESUMEN

Interferon (IFN) is a vital antiviral factor in host in the early stages after the viral invasion. Meanwhile, viruses have to survive by taking advantage of the cellular machinery and complete their replication. As a result, viruses evolved several immune escape mechanisms to inhibit host IFN expression. However, the mechanisms used to escape the host's IFN system are still unclear for infectious hematopoietic necrosis virus (IHNV). In this study, we report that the N protein of IHNV inhibits IFN1 production in rainbow trout by degrading the MITA. Firstly, the upregulation of IFN1 promoter activity stimulated by poly I:C was suppressed by IHNV infection. Consistent with this result, the overexpression of the N protein of IHNV blocked the IFN1 transcription that was activated by poly I:C and MITA. Secondly, MITA was remarkably decreased by the overexpression of N protein at the protein level. Further analysis demonstrated that the N protein targeted MITA and promoted the ubiquitination of MITA. Taken together, these data suggested that the production of rainbow trout IFN1 could be suppressed by the N protein of IHNV via degrading MITA.


Asunto(s)
Proteínas de Peces/genética , Virus de la Necrosis Hematopoyética Infecciosa/inmunología , Interferones/inmunología , Proteínas de la Membrana/genética , Proteínas de la Nucleocápside/inmunología , Oncorhynchus mykiss/inmunología , Animales , Antivirales/farmacología , Células HEK293 , Interacciones Microbiota-Huesped/inmunología , Humanos , Virus de la Necrosis Hematopoyética Infecciosa/genética , Proteínas de la Nucleocápside/genética , Oncorhynchus mykiss/virología , Poli I-C/farmacología , Infecciones por Rhabdoviridae , Ubiquitinación
19.
Mol Psychiatry ; 25(11): 3010-3019, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-30120420

RESUMEN

It is believed that genetic factors play a large role in the development of many cognitive and neurological processes; however, epidemiological evidence for the genetic basis of childhood neurodevelopment is very limited. Identification of the genetic polymorphisms associated with early-stage neurodevelopment will help elucidate biological mechanisms involved in neuro-behavior and provide a better understanding of the developing brain. To search for such variants, we performed a genome-wide association study (GWAS) for infant mental and motor ability at two years of age with mothers and children recruited from cohorts in Bangladesh and Mexico. Infant ability was assessed using mental and motor composite scores calculated with country-specific versions of the Bayley Scales of Infant Development. A missense variant (rs1055153) located in the gene WWTR1 reached genome-wide significance in association with mental composite score (meta-analysis effect size of minor allele ßmeta = -6.04; 95% CI: -8.13 to -3.94; P = 1.56×10-8). Infants carrying the minor allele reported substantially lower cognitive scores in both cohorts, and this variant is predicted to be in the top 0.3% of most deleterious substitutions in the human genome. Fine mapping and region-based association testing provided additional suggestive evidence that both WWTR1 and a second gene, LRP1B, were associated with infant cognitive ability. Comparisons with recently conducted GWAS in intelligence and educational attainment indicate that our phenotypes do not possess a high genetic correlation with either adolescent or adult cognitive traits, suggesting that infant neurological assessments should be treated as an independent outcome of interest. Additional functional studies and replication efforts in other cohorts may help uncover new biological pathways and genetic architectures that are crucial to the developing brain.


Asunto(s)
Cognición , Sitios Genéticos/genética , Genoma Humano/genética , Adulto , Alelos , Bangladesh , Preescolar , Estudios de Cohortes , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino , México , Madres , Destreza Motora , Fenotipo
20.
Dalton Trans ; 48(30): 11186-11190, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31273361

RESUMEN

A novel azide-bridged copper compound without an auxiliary ligand has been synthesized and characterized by single-crystal diffraction analysis. The compound consists of 1D double chains with end-on (EO) azide bridges. Furthermore, the neighboring chains are connected by weak coordination bonds, which leads to the formation of a 3D architecture. Low-temperature magnetic measurements reveal that antiferromagnetic interactions are dominant, with concomitant spin-canted antiferromagnetism.

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