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1.
Proc Natl Acad Sci U S A ; 121(20): e2319115121, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38709931

ABSTRACT

The endosomal sorting complexes required for transport (ESCRTs) are responsible for membrane remodeling in many cellular processes, such as multivesicular body biogenesis, viral budding, and cytokinetic abscission. ESCRT-III, the most abundant ESCRT subunit, assembles into flat spirals as the primed state, essential to initiate membrane invagination. However, the three-dimensional architecture of ESCRT-III flat spirals remained vague for decades due to highly curved filaments with a small diameter and a single preferred orientation on the membrane. Here, we unveiled that yeast Snf7, a component of ESCRT-III, forms flat spirals on the lipid monolayers using cryogenic electron microscopy. We developed a geometry-constrained Euler angle-assigned reconstruction strategy and obtained moderate-resolution structures of Snf7 flat spirals with varying curvatures. Our analyses showed that Snf7 subunits recline on the membrane with N-terminal motifs α0 as anchors, adopt an open state with fused α2/3 helices, and bend α2/3 gradually from the outer to inner parts of flat spirals. In all, we provide the orientation and conformations of ESCRT-III flat spirals on the membrane and unveil the underlying assembly mechanism, which will serve as the initial step in understanding how ESCRTs drive membrane abscission.


Subject(s)
Cryoelectron Microscopy , Endosomal Sorting Complexes Required for Transport , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Endosomal Sorting Complexes Required for Transport/metabolism , Endosomal Sorting Complexes Required for Transport/chemistry , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/chemistry , Saccharomyces cerevisiae Proteins/ultrastructure , Saccharomyces cerevisiae/metabolism , Cell Membrane/metabolism
2.
Article in English | MEDLINE | ID: mdl-38602856

ABSTRACT

Estimating the rigid transformation with 6 degrees of freedom based on a putative 3D correspondence set is a crucial procedure in point cloud registration. Existing correspondence identification methods usually lead to large outlier ratios (> 95% is common), underscoring the significance of robust registration methods. Many researchers turn to parameter search-based strategies (e.g., Branch-and-Bround) for robust registration. Although related methods show high robustness, their efficiency is limited to the high-dimensional search space. This paper proposes a heuristics-guided parameter search strategy to accelerate the search while maintaining high robustness. We first sample some correspondences (i.e., heuristics) and then just need to sequentially search the feasible regions that make each sample an inlier. Our strategy largely reduces the search space and can guarantee accuracy with only a few inlier samples, therefore enjoying an excellent trade-off between efficiency and robustness. Since directly parameterizing the 6-dimensional nonlinear feasible region for efficient search is intractable, we construct a three-stage decomposition pipeline to reparameterize the feasible region, resulting in three lower-dimensional sub-problems that are easily solvable via our strategy. Besides reducing the searching dimension, our decomposition enables the leverage of 1-dimensional interval stabbing at all three stages for searching acceleration. Moreover, we propose a valid sampling strategy to guarantee our sampling effectiveness, and a compatibility verification setup to further accelerate our search. Extensive experiments on both simulated and real-world datasets demonstrate that our approach exhibits comparable robustness with state-of-the-art methods while achieving a significant efficiency boost.

3.
Front Immunol ; 15: 1348836, 2024.
Article in English | MEDLINE | ID: mdl-38646523

ABSTRACT

Dabie Banda virus (DBV), a tick-borne pathogen, was first identified in China in 2009 and causes profound symptoms including fever, leukopenia, thrombocytopenia and multi-organ dysfunction, which is known as severe fever with thrombocytopenia syndrome (SFTS). In the last decade, global incidence and mortality of SFTS increased significantly, especially in East Asia. Though previous studies provide understandings of clinical and immunological characteristics of SFTS development, comprehensive insight of antiviral immunity response is still lacking. Here, we intensively discuss the antiviral immune response after DBV infection by integrating previous ex- and in-vivo studies, including innate and adaptive immune responses, anti-viral immune responses and long-term immune characters. A comprehensive overview of potential immune targets for clinical trials is provided as well. However, development of novel strategies for improving the prognosis of the disease remains on challenge. The current review may shed light on the establishment of immunological interventions for the critical disease SFTS.


Subject(s)
Phlebovirus , Severe Fever with Thrombocytopenia Syndrome , Animals , Humans , Adaptive Immunity , Immunity, Innate , Phlebovirus/immunology , Severe Fever with Thrombocytopenia Syndrome/immunology , Severe Fever with Thrombocytopenia Syndrome/therapy
4.
Int J Biol Macromol ; 265(Pt 1): 130642, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38460644

ABSTRACT

How selectively increase blood-tumor barrier (BTB) permeability is crucial to enhance the delivery of chemotherapeutic agents to brain tumor tissues. In this study, we established in vitro models of the blood-brain barrier (BBB) and BTB using endothelial cells (ECs) co-cultured with human astrocytes (AECs) and glioma cells (GECs), respectively. The findings revealed high expressions of the RNA-binding protein FXR1 and SNORD63 in GECs, where FXR1 was found to bind and stabilize SNORD63. Knockdown of FXR1 resulted in decreased expression of tight-junction-related proteins and increased BTB permeability by down-regulating SNORD63. SNORD63 played a role in mediating the 2'-O-methylation modification of POU6F1 mRNA, leading to the downregulation of POU6F1 protein expression. POU6F1 showed low expression in GECs and acted as a transcription factor to regulate BTB permeability by binding to the promoter regions of ZO-1, occludin, and claudin-5 mRNAs and negatively regulating their expressions. Finally, the targeted regulation of FXR1, SNORD63, and POU6F1 expressions, individually or in combination, effectively enhanced doxorubicin passage through the BTB and induced apoptosis in glioma cells. This study aims to elucidate the underlying mechanism of the FXR1/SNORD63/POU6F1 axis in regulating BTB permeability, offering a novel strategy to improve the efficacy of glioma chemotherapy.


Subject(s)
Brain Neoplasms , Glioma , Hematologic Neoplasms , MicroRNAs , POU Domain Factors , Humans , MicroRNAs/genetics , Endothelial Cells/metabolism , Zonula Occludens-1 Protein/genetics , Zonula Occludens-1 Protein/metabolism , Brain Neoplasms/pathology , Glioma/pathology , Blood-Brain Barrier/metabolism , Tight Junction Proteins/metabolism , Occludin/genetics , Hematologic Neoplasms/pathology , Permeability , Methylation , Capillary Permeability , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism
5.
Proc Natl Acad Sci U S A ; 121(9): e2311160121, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38377189

ABSTRACT

Glioblastomas (GBMs) are the most lethal primary brain tumors with limited survival, even under aggressive treatments. The current therapeutics for GBMs are flawed due to the failure to accurately discriminate between normal proliferating cells and distinctive tumor cells. Mitochondria are essential to GBMs and serve as potential therapeutical targets. Here, we utilize cryo-electron tomography to quantitatively investigate nanoscale details of randomly sampled mitochondria in their native cellular context of GBM cells. Our results show that compared with cancer-free brain cells, GBM cells own more inter-mitochondrial junctions of several types for communications. Furthermore, our tomograms unveil microtubule-dependent mitochondrial nanotunnel-like bridges in the GBM cells as another inter-mitochondrial structure. These quantified inter-mitochondrial features, together with other mitochondria-organelle and intra-mitochondrial ones, are sufficient to distinguish GBM cells from cancer-free brain cells under scrutiny with predictive modeling. Our findings decipher high-resolution inter-mitochondrial structural signatures and provide clues for diagnosis and therapeutic interventions for GBM and other mitochondria-related diseases.


Subject(s)
Brain Neoplasms , Glioblastoma , Humans , Glioblastoma/pathology , Brain Neoplasms/pathology , Electron Microscope Tomography , Brain/pathology , Mitochondria/pathology
6.
Soft Robot ; 11(2): 320-337, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38324014

ABSTRACT

In this article, we present a novel and generic data-driven method to servo-control the 3-D shape of continuum and soft robots based on proprioceptive sensing feedback. Developments of 3-D shape perception and control technologies are crucial for continuum and soft robots to perform tasks autonomously in surgical interventions. However, owing to the nonlinear properties of continuum robots, one main difficulty lies in the modeling of them, especially for soft robots with variable stiffness. To address this problem, we propose a versatile learning-based adaptive shape controller by leveraging proprioception of 3-D configuration from fiber Bragg grating (FBG) sensors, which can online estimate the unknown model of continuum robot against unexpected disturbances and exhibit an adaptive behavior to the unmodeled system without priori data exploration. Based on a new composite adaptation algorithm, the asymptotic convergences of the closed-loop system with learning parameters have been proven by Lyapunov theory. To validate the proposed method, we present a comprehensive experimental study using two continuum and soft robots both integrated with multicore FBGs, including a robotic-assisted colonoscope and multisection extensible soft manipulators. The results demonstrate the feasibility, adaptability, and superiority of our controller in various unstructured environments, as well as phantom experiments.

7.
BMC Med ; 22(1): 65, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38355513

ABSTRACT

BACKGROUND: Establishing whether there is a potential relationship between glucagon-like peptide 1 receptor agonists (GLP-1RAs) and suicidal or self-injurious behaviors (SSIBs) is crucial for public safety. This study investigated the potential association between GLP-1RAs and SSIBs by exploring the FDA Adverse Event Reporting System (FAERS) database. METHODS: A disproportionality analysis was conducted using post-marketing data from the FAERS repository (2018 Q1 to 2022 Q4). SSIB cases associated with GLP-1RAs were identified and analyzed through disproportionality analysis using the information component. The parametric distribution with a goodness-of-fit test was employed to analyze the time-to-onset, and the Ω shrinkage was used to evaluate the potential effect of co-medication on the occurrence of SSIBs. RESULTS: In total, 204 cases of SSIBs associated with GLP-1RAs, including semaglutide, liraglutide, dulaglutide, exenatide, and albiglutide, were identified in the FAERS database. Time-of-onset analysis revealed no consistent mechanism for the latency of SSIBs in patients receiving GLP-1RAs. The disproportionality analysis did not indicate an association between GLP-1RAs and SSIBs. Co-medication analysis revealed 81 cases with antidepressants, antipsychotics, and benzodiazepines, which may be proxies of mental health comorbidities. CONCLUSIONS: We found no signal of disproportionate reporting of an association between GLP-1RA use and SSIBs. Clinicians need to maintain heightened vigilance on patients premedicated with neuropsychotropic drugs. This contributes to the greater acceptance of GLP-1RAs in patients with type 2 diabetes mellitus or obesity.


Subject(s)
Diabetes Mellitus, Type 2 , Humans , Diabetes Mellitus, Type 2/complications , Hypoglycemic Agents/therapeutic use , Glucagon-Like Peptide-1 Receptor Agonists , Pharmacovigilance , Suicidal Ideation
8.
World Neurosurg ; 185: 181-192, 2024 May.
Article in English | MEDLINE | ID: mdl-38286321

ABSTRACT

OBJECTIVE: This study aimed to evaluate the safety and efficacy of the Gekko coil system in treating intracranial aneurysms (IAs) in clinical practice. METHODS: A prospective multicenter randomized open-label parallel positive control noninferiority trial was conducted by 11 centers in China. Patients with a target IA were randomized 1:1 to coiling with either Gekko or Axium coils. The primary outcome was successful aneurysm occlusion at 6 months postoperative follow-up, whereas the secondary outcomes included the successful occlusion aneurysm rate in the immediate postoperative period, recanalization rate at the 6 months follow-up, and technical success and security. RESULTS: Between May 2018 and September 2020, 256 patients were enrolled and randomized. Per-protocol analysis showed that the successful aneurysm occlusion rate at 6 months was 96.08% for the Gekko coil group compared with 96.12% in the Axium coil group, with a difference of -0.04% (P = 0.877). The successful immediate aneurysm occlusion rates were 86.00% and 77.45% in the Gekko coil group and the Axium coil group, respectively, showing no significant difference between the 2 groups (P = 0.116), whereas the recanalization rates during the 6 months follow-up were 2.02% and 1.96% in the Gekko and Axium coil groups, respectively, which was not statistically significant (P = 1.000). CONCLUSIONS: This trial showed that the Gekko coil system was noninferior to the Axium coil system in terms of efficacy and safety for IA embolization. In clinical practice, the Gekko coil system can be considered safe and effective for treating patients with IA.


Subject(s)
Embolization, Therapeutic , Intracranial Aneurysm , Humans , Intracranial Aneurysm/therapy , Intracranial Aneurysm/surgery , Female , Male , Middle Aged , China , Prospective Studies , Treatment Outcome , Aged , Embolization, Therapeutic/instrumentation , Embolization, Therapeutic/methods , Adult , Endovascular Procedures/methods , Endovascular Procedures/instrumentation
10.
IEEE Trans Biomed Eng ; 71(2): 433-445, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37594869

ABSTRACT

OBJECTIVE: Although there have been studies conducted on the instantaneous remote center of motion (RCM) mechanism, the general closed-loop control method has not been studied. Thus, this article fills that gap and employs the advantages of this mechanism to develop a novel injection system. METHODS: The injection prototype involves the instantaneous RCM mechanism, insertion unit and injection unit. The RCM system is investigated in the presence of time-varying axial stiffness of the screw drive and underactuated case. For safe interaction, compliance control is designed in the insertion system. The stability of all separate systems is investigated with the bounded parameter variation rate. The injection prototype and a robot end-effector were then combined to perform injection. RESULTS: Our RCM prototype can achieve a large workspace, and its control effectiveness was verified by multiple frameworks and comparison with previous studies. Compliance-controlled insertion can achieve accurate depth regulation and zero-impedance control for manually operating the needle. With the help of three-dimensional reconstruction and hand/eye calibration, the manipulator can guide the injection prototype to a proper pose for injection of a face model. CONCLUSION: The injection prototype was successfully designed. The effectiveness of the whole control system was verified by simulations and experiments. The particular robotic injection task can be performed by the prototype. SIGNIFICANCE: This article provides alternative schemes for developing an instantaneous RCM system, screw drive-based surgical tool, and robotic insertion with small needles.


Subject(s)
Robotic Surgical Procedures , Robotics , Surgery, Computer-Assisted , Robotic Surgical Procedures/methods , Equipment Design , Surgery, Computer-Assisted/methods , Needles , Motion
11.
Int J Biol Macromol ; 257(Pt 1): 128409, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38016610

ABSTRACT

Angiogenesis plays a major role in tumor initiation, progression, and metastasis. This is why finding antiangiogenic targets is essential in the treatment of gliomas. In this study, NSUN2 and LINC00324 were significantly upregulated in conditionally cultured glioblastoma endothelial cells (GECs). Knockdown of NSUN2 or LINC00324 inhibits GECs angiogenesis. NSUN2 increased the stability of LINC00324 by m5C modification and upregulated LINC00324 expression. LINC00324 competes with the 3'UTR of CBX3 mRNA to bind to AUH protein, reducing the degradation of CBX3 mRNA. In addition, CBX3 directly binds to the promoter region of VEGFR2, enhances VEGFR2 transcription, and promotes GECs angiogenesis. These findings demonstrated NSUN2/LINC00324/CBX3 axis plays a crucial role in regulating glioma angiogenesis, which provides new strategies for glioma therapy.


Subject(s)
Endothelial Cells , Glioma , Humans , Endothelial Cells/metabolism , Angiogenesis , Cell Proliferation/genetics , Glioma/pathology , RNA, Messenger/genetics , Chromosomal Proteins, Non-Histone
12.
Nat Commun ; 14(1): 8213, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-38081830

ABSTRACT

Achieving low-carbon development of the cement industry in the developing countries is fundamental to global emissions abatement, considering the local construction industry's rapid growth. However, there is currently a lack of systematic and accurate accounting and projection of cement emissions in developing countries, which are characterized with lower basic economic country condition. Here, we provide bottom-up quantifications of emissions from global cement production and reveal a regional shift in the main contributors to global cement CO2 emissions. The study further explores cement emissions over 2020-2050 that correspond to different housing and infrastructure conditions and emissions mitigation options for all developing countries except China. We find that cement emissions in developing countries except China will reach 1.4-3.8 Gt in 2050 (depending on different industrialization trajectories), compared to their annual emissions of 0.7 Gt in 2018. The optimal combination of low-carbon measures could contribute to reducing annual emissions by around 65% in 2050 and cumulative emissions by around 48% over 2020-2050. The efficient technological paths towards a low carbon future of cement industry vary among the countries and infrastructure scenarios. Our results are essential to understanding future emissions patterns of the cement industry in the developing countries and can inform policies in the cement sector that contribute to meeting the climate targets set out in the Paris Agreement.

13.
J Transl Med ; 21(1): 865, 2023 11 29.
Article in English | MEDLINE | ID: mdl-38017505

ABSTRACT

BACKGROUND: Previous studies have demonstrated that natural killer (NK) cells migrated into the liver from peripheral organs and exerted cytotoxic effects on hepatocytes in virus-induced liver failure. AIM: This study aimed to investigate the potential therapeutic role of chemokine receptors in the migration of NK cells in a murine hepatitis  virus strain 3 (MHV-3)-induced fulminant hepatic failure (MHV-3-FHF) model and its mechanism. RESULTS: By gene array analysis, chemokine (C-C motif) receptor 5 (CCR5) was found to have remarkably elevated expression levels in hepatic NK cells after MHV-3 infection. The number of hepatic CCR5+ conventional NK (cNK) cells increased and peaked at 48 h after MHV-3 infection, while the number of hepatic resident NK (rNK) cells steadily declined. Moreover, the expression of CCR5-related chemokines, including macrophage inflammatory protein (MIP)-1α, MIP-1ß and regulated on activation, normal T-cell expressed and secreted (RANTES) was significantly upregulated in MHV-3-infected hepatocytes. In an in vitro Transwell migration assay, CCR5-blocked splenic cNK cells showed decreased migration towards MHV-3-infected hepatocytes, and inhibition of MIP-1ß or RANTES but not MIP-1α decreased cNK cell migration. Moreover, CCR5 knockout (KO) mice displayed reduced infiltration of hepatic cNK cells after MHV-3 infection, accompanied by attenuated liver injury and improved mouse survival time. Adoptive transfer of cNK cells from wild-type mice into CCR5 KO mice resulted in the abundant accumulation of hepatic cNK cells and aggravated liver injury. Moreover, pharmacological inhibition of CCR5 by maraviroc reduced cNK cell infiltration in the liver and liver injury in the MHV-3-FHF model. CONCLUSION: The CCR5-MIP-1ß/RANTES axis played a critical role in the recruitment of cNK cells to the liver during MHV-3-induced liver injury. Targeted inhibition of CCR5 provides a therapeutic approach to ameliorate liver damage during virus-induced acute liver injury.


Subject(s)
Liver Failure, Acute , Murine hepatitis virus , Animals , Mice , Chemokine CCL3 , Chemokine CCL4 , Chemokine CCL5 , Chemokines , Chemokines, CC , Killer Cells, Natural , Receptors, CCR5 , Receptors, Chemokine
14.
Cell Death Dis ; 14(11): 745, 2023 11 15.
Article in English | MEDLINE | ID: mdl-37968257

ABSTRACT

Glioblastoma multiforme (GBM) is a highly vascularized malignant cancer of the central nervous system, and the presence of vasculogenic mimicry (VM) severely limits the effectiveness of anti-vascular therapy. In this study, we identified downregulated circHECTD1, which acted as a key VM-suppressed factor in GBM. circHECTD1 elevation significantly inhibited cell proliferation, migration, invasion and tube-like structure formation in GBM. RIP assay was used to demonstrate that the flanking intron sequence of circHECTD1 can be specifically bound by RBMS3, thereby inducing circHECTD1 formation to regulate VM formation in GBM. circHECTD1 was confirmed to possess a strong protein-encoding capacity and the encoded functional peptide 463aa was identified by LC-MS/MS. Both circHECTD1 and 463aa significantly inhibited GBM VM formation in vivo and in vitro. Analysis of the 463aa protein sequence revealed that it contained a ubiquitination-related domain and promoted NR2F1 degradation by regulating the ubiquitination of the NR2F1 at K396. ChIP assay verified that NR2F1 could directly bind to the promoter region of MMP2, MMP9 and VE-cadherin, transcriptionally promoting the expression of VM-related proteins, which in turn enhanced VM formation in GBM. In summary, we clarified a novel pathway for RBMS3-induced circHECTD1 encoding functional peptide 463aa to mediate the ubiquitination of NR2F1, which inhibited VM formation in GBM. This study aimed to reveal new mechanisms of GBM progression in order to provide novel approaches and strategies for the anti-vascular therapy of GBM. The schematic illustration showed the inhibitory effect of circHECTD1-463aa in the VM formation in GBM.


Subject(s)
Glioblastoma , Humans , Glioblastoma/genetics , Glioblastoma/pathology , Cell Line, Tumor , Chromatography, Liquid , Tandem Mass Spectrometry , Peptides/genetics , Peptides/metabolism , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/metabolism , Trans-Activators/metabolism , RNA-Binding Proteins
15.
Cell Biol Toxicol ; 39(6): 3323-3340, 2023 12.
Article in English | MEDLINE | ID: mdl-37906341

ABSTRACT

Human malignant gliomas are the most common and aggressive primary malignant tumors of the human central nervous system. Vasculogenic mimicry (VM), which refers to the formation of a tumor blood supply system independently of endothelial cells, contributes to the malignant progression of glioma. Therefore, VM is considered a potential target for glioma therapy. Accumulated evidence indicates that alterations in SUMOylation, a reversible post-translational modification, are involved in tumorigenesis and progression. In the present study, we found that UBA2 and RALY were upregulated in glioma tissues and cell lines. Downregulation of UBA2 and RALY inhibited the migration, invasion, and VM of glioma cells. RALY can be SUMOylated by conjugation with SUMO1, which is facilitated by the overexpression of UBA2. The SUMOylation of RALY increases its stability, which in turn increases its expression as well as its promoting effect on FOXD1 mRNA. The overexpression of FOXD1 promotes DKK1 transcription by activating its promoter, thereby promoting glioma cell migration, invasion, and VM. Remarkably, the combined knockdown of UBA2, RALY, and FOXD1 resulted in the smallest tumor volumes and the longest survivals of nude mice in vivo. UBA2/RALY/FOXD1/DKK1 axis may play crucial roles in regulating VM in glioma, which may contribute to the development of potential strategies for the treatment of gliomas.


Subject(s)
Brain Neoplasms , Glioma , Mice , Animals , Humans , Brain Neoplasms/metabolism , Sumoylation , Mice, Nude , Endothelial Cells/metabolism , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/metabolism , Glioma/genetics , Glioma/metabolism , Cell Line, Tumor , Heterogeneous-Nuclear Ribonucleoprotein Group C/genetics , Heterogeneous-Nuclear Ribonucleoprotein Group C/metabolism , Ubiquitin-Activating Enzymes/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Forkhead Transcription Factors/genetics
16.
Int J Mol Sci ; 24(18)2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37762361

ABSTRACT

The flhDC operon of Escherichia coli encodes a transcription factor that initiates flagella synthesis, elevates flagella construction and enhances cell motility, which all are energetically costly and highly regulated processes. In this study, we found that overexpression of flhDC genes from a strong regulatable pN15E6 plasmid could inhibit the growth of E. coli host cells and even eventually cause death. We used transcriptome analysis to investigate the mechanism of flhDC overexpression lethal to host bacteria. The results showed that a total of 568 differentially expressed genes (DEGs), including 378 up-regulated genes and 190 down-regulated genes were detected when the flhDC genes were over-expressed. Functional enrichment analysis results showed that the DEGs are related to a series of crucial biomolecular processes, including flagella synthesis, oxidative phosphorylation and pentose phosphate pathways, etc. We then examined, using RT-qPCR, the expression of key genes of the oxidative phosphorylation pathway at different time points after induction. Results showed that their expression increased in the early stage and decreased afterward, which was suggested to be the result of feedback on the overproduction of ROS, a strong side effect product of the elevated oxidative phosphorylation process. To further verify the level of ROS output, flhDC over-expressed bacteria cells were stained with DCHF-DA and a fluorescence signal was detected using flow cytometry. Results showed that the level of ROS output was higher in cells with over-expressed flhDC than in normal controls. Besides, we found upregulation of other genes (recN and zwf) that respond to ROS damage. This leads to the conclusion that the bacterial death led by the overexpression of flhDC genes is caused by damage from ROS overproduction, which leaked from the oxidative phosphorylation pathway.


Subject(s)
Escherichia coli Proteins , Escherichia coli , Escherichia coli/genetics , Escherichia coli/metabolism , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Trans-Activators/metabolism , Reactive Oxygen Species/metabolism , Genes, Regulator , Gene Expression Profiling , Flagella/metabolism , Gene Expression Regulation, Bacterial , Bacterial Proteins/metabolism
17.
Biotechnol Biofuels Bioprod ; 16(1): 124, 2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37542329

ABSTRACT

BACKGROUND: Sesquiterpenes are designated as a large class of plant-derived natural active compounds, which have wide applications in industries of energy, food, cosmetics, medicine and agriculture. Neither plant extraction nor chemical synthesis can meet the massive market demands and sustainable development goals. Biosynthesis in microbial cell factories represents an eco-friendly and high-efficient way. Among several microorganisms, Saccharomyces cerevisiae exhibited the potential as a chassis for bioproduction of various sesquiterpenes due to its native mevalonate pathway. However, its inefficient nature limits biosynthesis of diverse sesquiterpenes at industrial grade. RESULTS: Herein, we exploited an artificial synthetic malonic acid-acetoacetyl-CoA (MAAC) metabolic pathway to switch central carbon metabolic flux for stable and efficient biosynthesis of sesquiterpene-based high-density biofuel precursor in S. cerevisiae. Through investigations at transcription and metabolism levels, we revealed that strains with rewired central metabolism can devote more sugars to ß-caryophyllene production. By optimizing the MVA pathway, the yield of ß-caryophyllene from YQ-4 was 25.8 mg/L, which was 3 times higher than that of the initial strain YQ-1. Strain YQ-7 was obtained by introducing malonic acid metabolic pathway. Combing the optimized flask fermentation process, the target production boosted by about 13-fold, to 328 mg/L compared to that in the strain YQ-4 without malonic acid metabolic pathway. CONCLUSION: This designed MAAC pathway for sesquiterpene-based high-density biofuel precursor synthesis can provide an impressive cornerstone for achieving a sustainable production of renewable fuels.

18.
Exp Neurol ; 367: 114477, 2023 09.
Article in English | MEDLINE | ID: mdl-37406957

ABSTRACT

Glioblastoma (GBM) is the most common malignant tumor of the central nervous system. Vasculogenic mimicry (VM) is a hematological system composed of tumor cells that exert blood perfusion without relying on vascular endothelial cells. The current poor results of anti-vascular therapy for clinical GBM are associated with the presence of VM; therefore, it is important to investigate VM formation in GBM. Our results demonstrate that STK24P1 encodes P1-121aa with a kinase structural domain, and in vitro kinase assays demonstrated that P1-121aa mediates modification of ELF2 phosphorylation. ChIP and dual luciferase reporter gene assays demonstrated that the transcription factor ELF2 binds to VE-cadherin and the VEGFR2 promoter region, thereby promoting VM formation in glioma cells. P1-121aa, encoded by the pseudogene STK24P1, phosphorylates ELF2 at S107, increasing the stability of the ELF2 protein. ELF2 promotes VEGFR2 and VE-cadherin expression at the transcriptional level, which in turn promotes VM in GBM. This study demonstrates the important roles of STK24P1, P1-121aa, and ELF2 in regulating VM in GBM, which could provide potential targets for GBM treatment.


Subject(s)
Glioblastoma , Humans , Glioblastoma/drug therapy , Phosphorylation , Endothelial Cells/metabolism , Neovascularization, Pathologic/drug therapy , Peptides/metabolism , Cell Line, Tumor , Transcription Factors/genetics , Transcription Factors/metabolism
19.
IEEE Trans Pattern Anal Mach Intell ; 45(11): 13035-13053, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37186524

ABSTRACT

Manhattan and Atlanta worlds hold for the structured scenes with only vertical and horizontal dominant directions (DDs). To describe the scenes with additional sloping DDs, a mixture of independent Manhattan worlds seems plausible, but may lead to unaligned and unrelated DDs. By contrast, we propose a novel structural model called Hong Kong world. It is more general than Manhattan and Atlanta worlds since it can represent the environments with slopes, e.g., a city with hilly terrain, a house with sloping roof, and a loft apartment with staircase. Moreover, it is more compact and accurate than a mixture of independent Manhattan worlds by enforcing the orthogonality constraints between not only vertical and horizontal DDs, but also horizontal and sloping DDs. We further leverage the structural regularity of Hong Kong world for the line-based SLAM. Our SLAM method is reliable thanks to three technical novelties. First, we estimate DDs/vanishing points in Hong Kong world in a semi-searching way. We use a new consensus voting strategy for search, instead of traditional branch and bound. This method is the first one that can simultaneously determine the number of DDs, and achieve quasi-global optimality in terms of the number of inliers. Second, we compute the camera pose by exploiting the spatial relations between DDs in Hong Kong world. This method generates concise polynomials, and thus is more accurate and efficient than existing approaches designed for unstructured scenes. Third, we refine the estimated DDs in Hong Kong world by a novel filter-based method. Then we use these refined DDs to optimize the camera poses and 3D lines, leading to higher accuracy and robustness than existing optimization algorithms. In addition, we establish the first dataset of sequential images in Hong Kong world. Experiments showed that our approach outperforms state-of-the-art methods in terms of accuracy and/or efficiency.

20.
CNS Neurosci Ther ; 29(10): 2811-2825, 2023 10.
Article in English | MEDLINE | ID: mdl-37066523

ABSTRACT

AIMS: The isocitrate dehydrogenase (IDH) phenotype is associated with reprogrammed energy metabolism in glioblastoma (GBM) cells. Small nucleolar RNAs (snoRNAs) are known to exert an important regulatory role in the energy metabolism of tumor cells. The purpose of this study was to investigate the role of C/D box snoRNA U3 and transcription factor zinc finger and BTB domain-containing 7A (ZBTB7A) in the regulation of aerobic glycolysis and the proliferative capacity of IDH1 wild-type (IDH1WT ) GBM cells. METHODS: Quantitative reverse transcription PCR and western blot assays were utilized to detect snoRNA U3 and ZBTB7A expression. U3 promoter methylation status was analyzed via bisulfite sequencing and methylation-specific PCR. Seahorse XF glycolysis stress assays, lactate production and glucose consumption measurement assays, and cell viability assays were utilized to detect glycolysis and proliferation of IDH1WT GBM cells. RESULTS: We found that hypomethylation of the CpG island in the promoter region of U3 led to the upregulation of U3 expression in IDH1WT GBM cells, and the knockdown of U3 suppressed aerobic glycolysis and the proliferation ability of IDH1WT GBM cells. We found that small nucleolar-derived RNA (sdRNA) U3-miR, a small fragment produced by U3, was able to bind to the ZBTB4 3'UTR region and reduce ZBTB7A mRNA stability, thereby downregulating ZBTB7A protein expression. Furthermore, ZBTB7A transcriptionally inhibited the expression of hexokinase 2 (HK2) and lactate dehydrogenase A (LDHA), which are key enzymes of aerobic glycolysis, by directly binding to the HK2 and LDHA promoter regions, thereby forming the U3/ZBTB7A/HK2 LDHA pathway that regulates aerobic glycolysis and proliferation of IDH1WT GBM cells. CONCLUSION: U3 enhances aerobic glycolysis and proliferation in IDH1WT GBM cells via the U3/ZBTB7A/HK2 LDHA axis.


Subject(s)
Glioblastoma , Humans , Glioblastoma/pathology , RNA, Small Nucleolar/metabolism , Isocitrate Dehydrogenase/genetics , Cell Line, Tumor , DNA-Binding Proteins/genetics , Transcription Factors/genetics , Glycolysis , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic
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