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1.
Proc Natl Acad Sci U S A ; 120(17): e2302448120, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37068250

RESUMO

The tropane alkaloids (TAs) cocaine and hyoscyamine have been used medicinally for thousands of years. To understand the evolutionary origins and trajectories of serial biosynthetic enzymes of TAs and especially the characteristic tropane skeletons, we generated the chromosome-level genome assemblies of cocaine-producing Erythroxylum novogranatense (Erythroxylaceae, rosids clade) and hyoscyamine-producing Anisodus acutangulus (Solanaceae, asterids clade). Comparative genomic and phylogenetic analysis suggested that the lack of spermidine synthase/N-methyltransferase (EnSPMT1) in ancestral asterids species contributed to the divergence of polyamine (spermidine or putrescine) methylation in cocaine and hyoscyamine biosynthesis. Molecular docking analysis and key site mutation experiments suggested that ecgonone synthases CYP81AN15 and CYP82M3 adopt different active-site architectures to biosynthesize the same product ecgonone from the same substrate in Erythroxylaceae and Solanaceae. Further synteny analysis showed different evolutionary origins and trajectories of CYP81AN15 and CYP82M3, particularly the emergence of CYP81AN15 through the neofunctionalization of ancient tandem duplication genes. The combination of structural biology and comparative genomic analysis revealed that ecgonone methyltransferase, which is responsible for the biosynthesis of characteristic 2-substituted carboxymethyl group in cocaine, evolved from the tandem copies of salicylic acid methyltransferase by the mutations of critical E216 and S153 residues. Overall, we provided strong evidence for the independent origins of serial TA biosynthetic enzymes on the genomic and structural level, underlying the chemotypic convergence of TAs in phylogenetically distant species.


Assuntos
Cocaína , Hiosciamina , Solanaceae , Filogenia , Simulação de Acoplamento Molecular , Tropanos , Solanaceae/genética , Genômica , Metiltransferases/genética
2.
Plant J ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995679

RESUMO

Bacterial leaf streak (BLS), caused by Xanthomonas oryzae pv. oryzicola (Xoc), is a major bacterial disease in rice. Transcription activator-like effectors (TALEs) from Xanthomonas can induce host susceptibility (S) genes and facilitate infection. However, knowledge of the function of Xoc TALEs in promoting bacterial virulence is limited. In this study, we demonstrated the importance of Tal10a for the full virulence of Xoc. Through computational prediction and gene expression analysis, we identified the hexokinase gene OsHXK5 as a host target of Tal10a. Tal10a directly binds to the gene promoter region and activates the expression of OsHXK5. CRISPR/Cas9-mediated gene editing in the effector binding element (EBE) of OsHXK5 significantly increases rice resistance to Xoc, while OsHXK5 overexpression enhances the susceptibility of rice plants and impairs rice defense responses. Moreover, simultaneous editing of the promoters of OsSULTR3;6 and OsHXK5 confers robust resistance to Xoc in rice. Taken together, our findings highlight the role of Tal10a in targeting OsHXK5 to promote infection and suggest that OsHXK5 represents a potential target for engineering rice resistance to Xoc.

3.
J Virol ; 98(1): e0155823, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38174926

RESUMO

Enterovirus A71 (EV-A71) can induce severe neurological complications and even fatal encephalitis in children, and it has caused several large outbreaks in Taiwan since 1998. We previously generated VP1 codon-deoptimized (VP1-CD) reverse genetics (rg) EV-A71 viruses (rgEV-A71s) that harbor a high-fidelity (HF) 3D polymerase. These VP1-CD-HF rgEV-A71s showed lower replication kinetics in vitro and decreased virulence in an Institute of Cancer Research (ICR) mouse model of EV-A71 infection, while still retaining their antigenicity in comparison to the wild-type virus. In this study, we aimed to further investigate the humoral and cellular immune responses elicited by VP1-CD-HF rgEV-A71s to assess the potential efficacy of these EV-A71 vaccine candidates. Following intraperitoneal (i.p.) injection of VP1-CD-HF rgEV-A71s in mice, we observed a robust induction of EV-A71-specific neutralizing IgG antibodies in the antisera after 21 days. Splenocytes isolated from VP1-CD-HF rgEV-A71s-immunized mice exhibited enhanced proliferative activities and cytokine production (IL-2, IFN-γ, IL-4, IL-6, and TNF-α) upon re-stimulation with VP1-CD-HF rgEV-A71, as compared to control mice treated with adjuvant only. Importantly, administration of antisera from VP1-CD-HF rgEV-A71s-immunized mice protected against lethal EV-A71 challenge in neonatal mice. These findings highlight that our generated VP1-CD-HF rgEV-A71 viruses are capable of inducing both cellular and humoral immune responses, supporting their potential as next-generation EV-A71 vaccines for combating EV-A71 infection.IMPORTANCEEV-A71 can cause severe neurological diseases and cause death in young children. Here, we report the development of synthetic rgEV-A71s with the combination of codon deoptimization and high-fidelity (HF) substitutions that generate genetically stable reverse genetics (rg) viruses as potential attenuated vaccine candidates. Our work provides insight into the development of low-virulence candidate vaccines through a series of viral genetic editing for maintaining antigenicity and genome stability and suggests a strategy for the development of an innovative next-generation vaccine against EV-A71.


Assuntos
Proteínas do Capsídeo , Enterovirus Humano A , Infecções por Enterovirus , RNA Polimerase Dependente de RNA , Animais , Camundongos , Anticorpos Antivirais/imunologia , Códon , Enterovirus Humano A/genética , Infecções por Enterovirus/imunologia , Vacinas Atenuadas , Proteínas do Capsídeo/genética , Imunidade Humoral , Imunidade Celular , Anticorpos Neutralizantes/imunologia , Vacinas Virais , Camundongos Endogâmicos ICR , Camundongos Endogâmicos BALB C , RNA Polimerase Dependente de RNA/genética
4.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36573474

RESUMO

Covalent inhibitors have received extensive attentions in the past few decades because of their long residence time, high binding efficiency and strong selectivity. Therefore, it is valuable to develop computational tools like molecular docking for modeling of covalent protein-ligand interactions or screening of potential covalent drugs. Meeting the needs, we have proposed HCovDock, an efficient docking algorithm for covalent protein-ligand interactions by integrating a ligand sampling method of incremental construction and a scoring function with covalent bond-based energy. Tested on a benchmark containing 207 diverse protein-ligand complexes, HCovDock exhibits a significantly better performance than seven other state-of-the-art covalent docking programs (AutoDock, Cov_DOX, CovDock, FITTED, GOLD, ICM-Pro and MOE). With the criterion of ligand root-mean-squared distance < 2.0 Å, HCovDock obtains a high success rate of 70.5% and 93.2% in reproducing experimentally observed structures for top 1 and top 10 predictions. In addition, HCovDock is also validated in virtual screening against 10 receptors of three proteins. HCovDock is computationally efficient and the average running time for docking a ligand is only 5 min with as fast as 1 sec for ligands with one rotatable bond and about 18 min for ligands with 23 rotational bonds. HCovDock can be freely assessed at http://huanglab.phys.hust.edu.cn/hcovdock/.


Assuntos
Algoritmos , Proteínas , Simulação de Acoplamento Molecular , Ligantes , Proteínas/química , Ligação Proteica
5.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36440949

RESUMO

Protein-protein interactions play an important role in many biological processes. However, although structure prediction for monomer proteins has achieved great progress with the advent of advanced deep learning algorithms like AlphaFold, the structure prediction for protein-protein complexes remains an open question. Taking advantage of the Transformer model of ESM-MSA, we have developed a deep learning-based model, named DeepHomo2.0, to predict protein-protein interactions of homodimeric complexes by leveraging the direct-coupling analysis (DCA) and Transformer features of sequences and the structure features of monomers. DeepHomo2.0 was extensively evaluated on diverse test sets and compared with eight state-of-the-art methods including protein language model-based, DCA-based and machine learning-based methods. It was shown that DeepHomo2.0 achieved a high precision of >70% with experimental monomer structures and >60% with predicted monomer structures for the top 10 predicted contacts on the test sets and outperformed the other eight methods. Moreover, even the version without using structure information, named DeepHomoSeq, still achieved a good precision of >55% for the top 10 predicted contacts. Integrating the predicted contacts into protein docking significantly improved the structure prediction of realistic Critical Assessment of Protein Structure Prediction homodimeric complexes. DeepHomo2.0 and DeepHomoSeq are available at http://huanglab.phys.hust.edu.cn/DeepHomo2/.


Assuntos
Aprendizado Profundo , Biologia Computacional/métodos , Proteínas/química , Algoritmos , Aprendizado de Máquina
6.
PLoS Pathog ; 19(2): e1011166, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36753521

RESUMO

Congenital human cytomegalovirus (HCMV) infection causes severe damage to the fetal brain, and the underlying mechanisms remain elusive. Cytokine signaling is delicately controlled in the fetal central nervous system to ensure proper development. Here we show that suppressor of cytokine signaling 3 (SOCS3), a negative feedback regulator of the IL-6 cytokine family signaling, was upregulated during HCMV infection in primary neural progenitor cells (NPCs) with a biphasic expression pattern. From viral protein screening, pUL97 emerged as the viral factor responsible for prolonged SOCS3 upregulation. Further, by proteomic analysis of the pUL97-interacting host proteins, regulatory factor X 7 (RFX7) was identified as the transcription factor responsible for the regulation. Depletion of either pUL97 or RFX7 prevented the HCMV-induced SOCS3 upregulation in NPCs. With a promoter-luciferase activity assay, we demonstrated that the pUL97 kinase activity and RFX7 were required for SOCS3 upregulation. Moreover, the RFX7 phosphorylation level was increased by either UL97-expressing or HCMV-infection in NPCs, suggesting that pUL97 induces RFX7 phosphorylation to drive SOCS3 transcription. We further revealed that elevated SOCS3 expression impaired NPC proliferation and migration in vitro and caused NPCs migration defects in vivo. Taken together, these findings uncover a novel regulatory mechanism of sustained SOCS3 expression in HCMV-infected NPCs, which perturbs IL-6 cytokine family signaling, leads to NPCs proliferation and migration defects, and consequently affects fetal brain development.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Humanos , Citomegalovirus/fisiologia , Interleucina-6/metabolismo , Proteômica , Fatores de Transcrição/metabolismo , Células-Tronco , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo
7.
PLoS Biol ; 20(12): e3001730, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36469518

RESUMO

The brain as a central regulator of stress integration determines what is threatening, stores memories, and regulates physiological adaptations across the aging trajectory. While sleep homeostasis seems to be linked to brain resilience, how age-associated changes intersect to adapt brain resilience to life history remains enigmatic. We here provide evidence that a brain-wide form of presynaptic active zone plasticity ("PreScale"), characterized by increases of active zone scaffold proteins and synaptic vesicle release factors, integrates resilience by coupling sleep, longevity, and memory during early aging of Drosophila. PreScale increased over the brain until mid-age, to then decreased again, and promoted the age-typical adaption of sleep patterns as well as extended longevity, while at the same time it reduced the ability of forming new memories. Genetic induction of PreScale also mimicked early aging-associated adaption of sleep patterns and the neuronal activity/excitability of sleep control neurons. Spermidine supplementation, previously shown to suppress early aging-associated PreScale, also attenuated the age-typical sleep pattern changes. Pharmacological induction of sleep for 2 days in mid-age flies also reset PreScale, restored memory formation, and rejuvenated sleep patterns. Our data suggest that early along the aging trajectory, PreScale acts as an acute, brain-wide form of presynaptic plasticity to steer trade-offs between longevity, sleep, and memory formation in a still plastic phase of early brain aging.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Drosophila melanogaster/genética , Sinapses/fisiologia , Envelhecimento/fisiologia , Encéfalo/fisiologia , Plasticidade Neuronal/fisiologia
8.
Drug Resist Updat ; 76: 101111, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38908233

RESUMO

Gemcitabine (GEM) based induction chemotherapy is a standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). However, approximately 15 % of patients are still resistant to GEM-containing chemotherapy, which leads to treatment failure. Nevertheless, the underlying mechanisms of GEM resistance remain poorly understood. Herein, based on a microarray analysis, we identified 221 dysregulated lncRNAs, of which, DYNLRB2-AS1 was one of the most upregulated lncRNAs in GEM-resistance NPC cell lines. DYNLRB2-AS1 was shown to function as contain an oncogenic lncRNA that promoted NPC GEM resistance, cell proliferation, but inhibited cell apoptosis. Mechanistically, DYNLRB2-AS1 could directly bind to the DHX9 protein and prevent its interaction with the E3 ubiquitin ligase PRPF19, and thus blocking PRPF19-mediated DHX9 degradation, which ultimately facilitated the repair of DNA damage in the presence of GEM. Clinically, higher DYNLRB2-AS1 expression indicated an unfavourable overall survival of NPC patients who received induction chemotherapy. Overall, this study identified the oncogenic lncRNA DYNLRB2-AS1 as an independent prognostic biomarker for patients with locally advanced NPC and as a potential therapeutic target for overcoming GEM chemoresistance in NPC.


Assuntos
RNA Helicases DEAD-box , Desoxicitidina , Gencitabina , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , RNA Longo não Codificante , Animais , Humanos , Antimetabólitos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ubiquitinação/efeitos dos fármacos
9.
Nano Lett ; 24(31): 9743-9749, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39072414

RESUMO

The dynamics of ion transport at the interface is the critical factor for determining the performance of an electrochemical energy storage device. While practical applications are realized in concentrated electrolytes and nanopores, there is a limited understanding of their ion dynamic features. Herein, we studied the interfacial ion dynamics in room-temperature ionic liquids by transient single-particle imaging with microsecond-scale resolution. We observed slowed-down dynamics at lower potential while acceleration was observed at higher potential. Combined with simulation, we found that the microstructure evolution of the electric double layer (EDL) results in potential-dependent kinetics. Then, we established a correspondence between the ion dynamics and interfacial ion composition. Besides, the ordered ion orientation within EDL is also an essential factor for accelerating interfacial ion transport. These results inspire us with a new possibility to optimize electrochemical energy storage through the good control of the rational design of the interfacial ion structures.

10.
Biochemistry ; 63(8): 958-968, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38426700

RESUMO

Bispecific antibodies (BsAbs) are undergoing continued development for applications in oncology and autoimmune diseases. While increasing activity by having more than one targeting arm, most BsAb engineering employs single Fc engagement as monoclonal antibodies. Here, we designed a novel immunoglobulin gamma-1 (IgG1)-derived dual-Fc BsAb containing two Fc regions and two distinct asymmetric antigen binding arms comprising a Fab arm and another VHH domain. In conjunction with the knob-into-hole technology, dual-Fc BsAbs could be produced with a high yield and good stability. We explore how Fc engineering effects on dual-Fc constructs could boost the desired therapeutic efficacy. This new format enabled simultaneous bispecific binding to corresponding antigens. Furthermore, compared to the one-Fc control molecules, dual-Fc BsAbs were shown to increase the avidity-based binding to FcγRs to result in higher ADCC and ADCP activities by potent avidity via binding to two antigens and Fc receptors. Overall, this novel BsAb format with enhanced effector functionalities provides a new option for antibody-based immunotherapy.


Assuntos
Anticorpos Biespecíficos , Anticorpos Biespecíficos/química , Fragmentos Fc das Imunoglobulinas/genética , Anticorpos Monoclonais
11.
J Am Chem Soc ; 146(32): 22145-22150, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39101883

RESUMO

A heat-driven catch-and-release strategy for CoCl2 capture is described. It is based on the use of an immobilized neutral dicyclohexylacetamide-based receptor L supported on polystyrene (PS-L). An X-ray diffraction analysis of a single crystal of L·CoCl2 revealed an ion-pair complex comprising a hexacoordinated cobalt cation [L·Co]2+ and a tetrachlorocobaltate anion [CoCl4]2-. Temperature dependent binding was seen, as inferred from UV-vis spectroscopic studies. Fits to the van't Hoff equation yielded values of ΔH° = 12.4 kJ/mol and ΔS° = 56.0 J/K·mol for L + CoCl2, and ΔH° = 16.5 kJ/mol and ΔS° = 85.0 J/K·mol for PS-L + CoCl2 in 95% ethanol. Consequently, cobalt capture and release are mediated by heating and cooling, respectively. The material PS-L exhibits a preference for binding cobalt over manganese and nickel as inferred from Langmuir-Freundlich isotherm analyses that revealed binding constants of KLF = 88.5 M-1 for CoCl2, 52.7 M-1 for MnCl2, and 49.7 M-1 for NiCl2. In a simulated ion mixture containing equimolar CoCl2, MnCl2, and NiCl2, ICP-MS analyses served to confirm that cobalt was selectively enriched to 52 mol % (from an initial level of ca. 32 mol %) after one catch-and-release cycle and 76.6% after three cycles. Our experimental results were validated by density functional theory calculations, which also show stronger binding of Co over Mn and Ni to L.

12.
J Am Chem Soc ; 146(6): 4078-4086, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38300153

RESUMO

Electronic waste recycling is a recognized global challenge that requires new strategies to bind and release critical materials selectively, such as cobalt present in lithium-ion batteries. To address this challenge, hierarchical 3D-printed porous polymer scaffolds bearing supramolecular receptors were prepared using vat photopolymerization and their cobalt binding profiles were examined as a function of matrix polarity. By combining high-resolution digital light processing (DLP) with polymerization-induced phase separation (PIPS), functional acrylic copolymer networks with micrometer-level precision of geometry and nanometer-level pores were generated. Covalent integration of a methacrylate-functionalized bisdicyclohexyl acetamide (BDCA-MA) receptor enabled binding and release of cobalt(II) chloride (CoCl2) via a solvent polarity switch mechanism involving a change in solvent from ethanol to water. The present structures proved reusable as shown by sustained high binding efficiency over five bind and release cycles. This platform represents a "green" and energy conscious method for future electronic waste recycling.

13.
Neurobiol Dis ; 199: 106577, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38914171

RESUMO

Proper topographically organized neural connections between the thalamus and the cerebral cortex are mandatory for thalamus function. Thalamocortical (TC) fiber growth begins during the embryonic period and completes by the third trimester of gestation, so that human neonates at birth have a thalamus with a near-facsimile of adult functional parcellation. Whether congenital neocortical anomaly (e.g., lissencephaly) affects TC connection in humans is unknown. Here, via diffusion MRI fiber-tractography analysis of long-term formalin-fixed postmortem fetal brain diagnosed as lissencephaly in comparison with an age-matched normal one, we found similar topological patterns of thalamic subregions and of internal capsule parcellated by TC fibers. However, lissencephaly fetal brain showed white matter structural changes, including fewer/less organized TC fibers and optic radiations, and much less cortical plate invasion by TC fibers - particularly around the shallow central sulcus. Diffusion MRI fiber tractography of normal fetal brains at 15, 23, and 26 gestational weeks (GW) revealed dynamic volumetric change of each parcellated thalamic subregion, suggesting coupled developmental progress of the thalamus with the corresponding cortex. Moreover, from GW23 and GW26 normal fetal brains, TC endings in the cortical plate could be delineated to reflect cumulative progressive TC invasion of cortical plate. By contrast, lissencephaly brain showed a dramatic decrease in TC invasion of the cortical plate. Our study thus shows the feasibility of diffusion MRI fiber tractography in postmortem long-term formalin-fixed fetal brains to disclose the developmental progress of TC tracts coordinating with thalamic and neocortical growth both in normal and lissencephaly fetal brains at mid-gestational stage.


Assuntos
Córtex Cerebral , Imagem de Tensor de Difusão , Lisencefalia , Vias Neurais , Tálamo , Humanos , Tálamo/diagnóstico por imagem , Tálamo/patologia , Tálamo/embriologia , Córtex Cerebral/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/embriologia , Lisencefalia/patologia , Lisencefalia/diagnóstico por imagem , Vias Neurais/patologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/embriologia , Imagem de Tensor de Difusão/métodos , Feto/patologia , Feto/diagnóstico por imagem , Idade Gestacional , Feminino , Masculino , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Substância Branca/embriologia , Imagem de Difusão por Ressonância Magnética/métodos
14.
Cancer Sci ; 115(1): 270-282, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37942534

RESUMO

Colorectal cancer (CRC) is a globally common cancer, and the serum carcinoembryonic antigen (sCEA) is widely applied as a diagnostic and prognostic tumor marker in CRC. This study aimed to elucidate the mechanism of CEA expression and corresponding clinical features to improve prognostic assessments. In CRC cells, hypomethylation of the CEACAM5 promoter enhanced CEA expression in HCT116 and HT29 cells with 5-aza-2'-deoxycytidine (5-Aza-dC) treatment. Our clinical data indicated that 64.7% (101/156) of CRC patients had an sCEA level above the normal range, and 76.2% (77/101) of those patients showed a lower average CpG methylation level of the CEACAM5 promoter. The methylation analysis showed that both CRC cell lines and patient samples shared the same critical methylation CpG regions at -200 to -500 and -1000 to -1400 bp of the CEACAM5 promoter. Patients with hypermethylation of the CEACAM5 promoter showed features of a BRAF mutation, TGFB2 mutation, microsatellite instability-high, and preference for right-sided colorectal cancer and peritoneal seeding presentation that had a similar clinical character to the consensus molecular subtype 1 (CMS1) of colorectal cancer. Additionally, hypermethylation of the CEACAM5 promoter combined with evaluated sCEA demonstrated the worst survival among the patients. Therefore, the methylation status of the CEACAM5 promoter also served as an effective biomarker for assessing disease prognosis. Results indicated that DNA methylation is a major regulatory mechanism for CEA expression in colorectal cancer. Moreover, our data also highlighted that patients in a subgroup who escaped from inactivation by DNA methylation had distinct clinical and pathological features and the worst survival.


Assuntos
Antígeno Carcinoembrionário , Neoplasias Colorretais , Humanos , Antígeno Carcinoembrionário/genética , Antígeno Carcinoembrionário/metabolismo , Relevância Clínica , Neoplasias Colorretais/patologia , Metilação de DNA/genética , Decitabina , Células HT29 , Regulação Neoplásica da Expressão Gênica , Ilhas de CpG/genética , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo
15.
J Virol ; 97(5): e0031323, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37097169

RESUMO

Human cytomegalovirus (HCMV) is a leading cause of congenital birth defects. Though the underlying mechanisms remain poorly characterized, mouse models of congenital CMV infection have demonstrated that the neuronal migration process is damaged. In this study, we evaluated the effects of HCMV infection on connexin 43 (Cx43), a crucial adhesion molecule mediating neuronal migration. We show in multiple cellular models that HCMV infection downregulated Cx43 posttranslationally. Further analysis identified the immediate early protein IE1 as the viral protein responsible for the reduction of Cx43. IE1 was found to bind the Cx43 C terminus and promote Cx43 degradation through the ubiquitin-proteasome pathway. Deletion of the Cx43-binding site in IE1 rendered it incapable of inducing Cx43 degradation. We validated the IE1-induced loss of Cx43 in vivo by introducing IE1 into the fetal mouse brain. Noteworthily, ectopic IE1 expression induced cortical atrophy and neuronal migration defects. Several lines of evidence suggest that these damages result from decreased Cx43, and restoration of Cx43 levels partially rescued IE1-induced interruption of neuronal migration. Taken together, the results of our investigation reveal a novel mechanism of HCMV-induced neural maldevelopment and identify a potential intervention target. IMPORTANCE Congenital CMV (cCMV) infection causes neurological sequelae in newborns. Recent studies of cCMV pathogenesis in animal models reveal ventriculomegaly and cortical atrophy associated with impaired neural progenitor cell (NPC) proliferation and migration. In this study, we investigated the mechanisms underlying these NPC abnormalities. We show that Cx43, a critical adhesion molecule mediating NPC migration, is downregulated by HCMV infection in vitro and HCMV-IE1 in vivo. We provide evidence that IE1 interacts with the C terminus of Cx43 to promote its ubiquitination and consequent degradation through the proteasome. Moreover, we demonstrate that introducing IE1 into mouse fetal brains led to neuronal migration defects, which was associated with Cx43 reduction. Deletion of the Cx43-binding region in IE1 or ectopic expression of Cx43 rescued the IE1-induced migration defects in vivo. Our study provides insight into how cCMV infection impairs neuronal migration and reveals a target for therapeutic interventions.


Assuntos
Conexina 43 , Infecções por Citomegalovirus , Citomegalovirus , Proteínas Imediatamente Precoces , Animais , Humanos , Recém-Nascido , Camundongos , Conexina 43/genética , Conexina 43/metabolismo , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo
16.
Bioinformatics ; 39(6)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37252823

RESUMO

MOTIVATION: Bone marrow (BM) examination is one of the most important indicators in diagnosing hematologic disorders and is typically performed under the microscope via oil-immersion objective lens with a total 100× objective magnification. On the other hand, mitotic detection and identification is critical not only for accurate cancer diagnosis and grading but also for predicting therapy success and survival. Fully automated BM examination and mitotic figure examination from whole-slide images is highly demanded but challenging and poorly explored. First, the complexity and poor reproducibility of microscopic image examination are due to the cell type diversity, delicate intralineage discrepancy within the multitype cell maturation process, cells overlapping, lipid interference and stain variation. Second, manual annotation on whole-slide images is tedious, laborious and subject to intraobserver variability, which causes the supervised information restricted to limited, easily identifiable and scattered cells annotated by humans. Third, when the training data are sparsely labeled, many unlabeled objects of interest are wrongly defined as background, which severely confuses AI learners. RESULTS: This article presents an efficient and fully automatic CW-Net approach to address the three issues mentioned above and demonstrates its superior performance on both BM examination and mitotic figure examination. The experimental results demonstrate the robustness and generalizability of the proposed CW-Net on a large BM WSI dataset with 16 456 annotated cells of 19 BM cell types and a large-scale WSI dataset for mitotic figure assessment with 262 481 annotated cells of five cell types. AVAILABILITY AND IMPLEMENTATION: An online web-based system of the proposed method has been created for demonstration (see https://youtu.be/MRMR25Mls1A).


Assuntos
Processamento de Imagem Assistida por Computador , Microscopia , Humanos , Exame de Medula Óssea , Reprodutibilidade dos Testes , Processamento de Imagem Assistida por Computador/métodos
17.
New Phytol ; 241(4): 1708-1719, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38084009

RESUMO

To play essential roles of manganese (Mn) in plant growth and development, it needs to be transported to different organs and tissues after uptake. However, the molecular mechanisms underlying Mn distribution between different tissues are poorly understood. We functionally characterized a member of rice natural resistance-associated macrophage protein (NRAMP) family, OsNramp5 in terms of its tissue specificity of gene expression, cell-specificity of protein localization, phenotypic analysis of leaf growth and response to Mn fluctuations. OsNramp5 is highly expressed in the leaf sheath. Immunostaining revealed that OsNramp5 is polarly localized at the proximal side of xylem parenchyma cells of the leaf sheath. Both the gene expression and protein abundance of OsNramp5 are unaffected by different Mn concentrations. Knockout of OsNramp5 decreased the distribution of Mn to the leaf sheath, but increased the distribution to the leaf blade at both low and high Mn supplies, resulting in reduced growth of leaf sheath. Furthermore, expression of OsNramp5 under the control of root-specific promoter in osnramp5 mutant complemented Mn uptake, but could not complement Mn distribution to the leaf sheath. These results indicate that OsNramp5 expressed in the leaf sheath plays an important role in unloading Mn from the xylem for the local distribution in rice.


Assuntos
Oryza , Oryza/metabolismo , Manganês/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo
18.
New Phytol ; 242(6): 2620-2634, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38600023

RESUMO

Iron (Fe) needs to be delivered to different organs and tissues of above-ground parts for playing its multiple physiological functions once it is taken up by the roots. However, the mechanisms underlying Fe distribution are poorly understood. We functionally characterized OsOPT7, a member of oligo peptide transporter family in terms of expression patterns, localization, transport activity and phenotypic analysis of knockdown lines. OsOPT7 was highly expressed in the nodes, especially in the uppermost node I, and its expression was upregulated by Fe-deficiency. OsOPT7 transports ferrous iron into the cells coupled with proton. Immunostaining revealed that OsOPT7 is mainly localized in the xylem parenchyma cells of the enlarged vascular bundles in the nodes and vascular tissues in the leaves. Knockdown of OsOPT7 did not affect the Fe uptake, but altered Fe distribution; less Fe was distributed to the new leaf, upper nodes and developing panicle, but more Fe was distributed to the old leaves. Furthermore, knockdown of OsOPT7 also resulted in less Fe distribution to the leaf sheath, but more Fe to the leaf blade. Taken together, OsOPT7 is involved in the xylem unloading of Fe for both long-distance distribution to the developing organs and local distribution within the leaf in rice.


Assuntos
Ferro , Oryza , Proteínas de Plantas , Xilema , Transporte Biológico , Regulação da Expressão Gênica de Plantas , Técnicas de Silenciamento de Genes , Ferro/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana Transportadoras/genética , Oryza/genética , Oryza/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Xilema/metabolismo
19.
J Med Virol ; 96(7): e29793, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39023111

RESUMO

Various vaccine platforms were developed and deployed against the COVID-19 disease. The Fc-mediated functions of IgG antibodies are essential in the adaptive immune response elicited by vaccines. However, the long-term changes of protein subunit vaccines and their combinations with messenger RNA (mRNA) vaccines are unknown. A total of 272 serum and plasma samples were collected from individuals who received first to third doses of the protein subunit Medigen, the mRNA (BNT, Moderna), or the adenovector AstraZeneca vaccines. The IgG subclass level was measured using enzyme-linked immunosorbent assay, and Fc-N glycosylation was measured using liquid chromatography coupled to tandem mass spectrometry. Antibody-dependent-cellular-phagocytosis (ADCP) and complement deposition (ADCD) of anti-spike (S) IgG antibodies were measured by flow cytometry. IgG1 and 3 reached the highest anti-S IgG subclass level. IgG1, 2, and 4 subclass levels significantly increased in mRNA- and Medigen-vaccinated individuals. Fc-glycosylation was stable, except in female BNT vaccinees, who showed increased bisection and decreased galactosylation. Female BNT vaccinees had a higher anti-S IgG titer than that of males. ADCP declined in all groups. ADCD was significantly lower in AstraZeneca-vaccinated individuals. Each vaccine produced specific long-term changes in Fc structure and function. This finding is critical when selecting a vaccine platform or combination to achieve the desired immune response.


Assuntos
Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunoglobulina G , SARS-CoV-2 , Vacinas de Subunidades Antigênicas , Vacinas de mRNA , Humanos , Imunoglobulina G/sangue , Feminino , Anticorpos Antivirais/sangue , Masculino , COVID-19/prevenção & controle , COVID-19/imunologia , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Adulto , Pessoa de Meia-Idade , Vacinas contra COVID-19/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/administração & dosagem , Glicosilação , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Idoso , RNA Mensageiro/genética , Adulto Jovem , Vacinas de Subunidades Proteicas
20.
Chemistry ; 30(18): e202303741, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38206884

RESUMO

Compared with Li+, Na+ with a smaller stokes radius has faster de-solvation kinetics. An electrolyte with ultralow sodium salt (0.3 M NaPF6) is used to reduce the cell cost. However, the organic-dominated interface, mainly derived from decomposed solvents (SSIP solvation structure), is defective for the long cycling performance of sodium ion batteries. In this work, the simple application of dual additives, including sodium difluoro(oxalato)borate (NaDFOB) and tris(trimethylsilyl)borate (TMSB), is demonstrated to improve the cycling performance of the hard carbon/NaNi1/3Fe1/3Mn1/3O2 cell by constructing interface films on the anode and cathode. A significant improvement on cycling stability has been achieved by incorporating dual additives of NaDFOB and TMSB. Particularly, the capacity retention increased from 17 % (baseline) to 79 % (w/w, 2.0 wt % NaDFOB) and 83 % (w/w, 2.0 wt % NaDFOB and 1.0 wt % TMSB) after 200 cycles at room temperature. Insight into the mechanism of improved interfacial properties between electrodes and electrolyte in ultralow concentration electrolyte has been investigated through a combination of theoretical computation and experimental techniques.

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