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1.
FASEB J ; 38(18): e23820, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39302257

ABSTRACT

Epstein-Barr virus (EBV), a common gamma herpesvirus, establishes a life-long latent infection in the host to defend against innate immune recognition, which is closely related to a variety of malignant tumors, but its specific mechanism is unclear. BFRF3, an EBV-encoded small capsid protein, is mainly involved in the assembly of the viral capsid structure and the maintenance of its stability. Here, we showed that BFRF3 can inhibit TNF-α-mediated NF-кB promoter activation. Moreover, BFRF3 downregulates NF-кB-mediated promoter activation and transcription of inflammatory cytokines, including IL-6 and IL-8. Dual-luciferase reporter assay demonstrated that BFRF3 restrains NF-кB promoter activity at or below the p65 level, and coimmunoprecipitation analysis revealed that BFRF3 not only interacts with p65 but also binds to its critical truncated Rel homology domain (RHD) and transcriptional activation domain (TAD). However, BFRF3 does not affect the dimerization of p65-p50, but overexpression of BFRF3 reduces the nuclear accumulation of p65, and the phosphorylation of p65 (Ser536) is repressed during BFRF3 transfection and EBV lytic infection, which promotes the proliferation of EBV. Overall, our study suggested that BFRF3 may play a crucial role in antiviral immunity to defend against EBV infection by inhibiting NF-κB activity.


Subject(s)
Capsid Proteins , Herpesvirus 4, Human , NF-kappa B , Signal Transduction , Transcription Factor RelA , Humans , Herpesvirus 4, Human/metabolism , Herpesvirus 4, Human/immunology , Herpesvirus 4, Human/physiology , Capsid Proteins/metabolism , Capsid Proteins/genetics , Transcription Factor RelA/metabolism , NF-kappa B/metabolism , HEK293 Cells , Epstein-Barr Virus Infections/metabolism , Epstein-Barr Virus Infections/virology , Epstein-Barr Virus Infections/immunology , Promoter Regions, Genetic , Tumor Necrosis Factor-alpha/metabolism
2.
J Biol Chem ; 299(3): 102918, 2023 03.
Article in English | MEDLINE | ID: mdl-36657642

ABSTRACT

Multiple proteins bind to telomeric DNA and are important for the role of telomeres in genome stability. A recent study established a broad-complex, tramtrack and bric-à-brac - zinc finger (BTB-ZF) protein, ZBTB10 (zinc finger and BTB domain-containing protein 10), as a telomeric variant repeat-binding protein at telomeres that use an alternative method for lengthening telomeres). ZBTB10 specifically interacts with the double-stranded telomeric variant repeat sequence TTGGGG by employing its tandem C2H2 zinc fingers (ZF1-2). Here, we solved the crystal structure of human ZBTB10 ZF1-2 in complex with a double-stranded DNA duplex containing the sequence TTGGGG to assess the molecular details of this interaction. Combined with calorimetric analysis, we identified the vital residues in TTGGGG recognition and determined the specific recognition mechanisms that are different from those of TZAP (telomere zinc finger-associated protein), a recently defined telomeric DNA-binding protein. Following these studies, we further identified a single amino-acid mutant (Arg767Gln) of ZBTB10 ZF1-2 that shows a preference for the telomeric DNA repeat TTAGGG sequence. We solved the cocrystal structure, providing a structural basis for telomeric DNA recognition by C2H2 ZF proteins.


Subject(s)
DNA-Binding Proteins , Repressor Proteins , Humans , DNA/metabolism , DNA-Binding Proteins/metabolism , Protein Binding , Repressor Proteins/metabolism , Telomere/metabolism , Zinc Fingers/genetics
3.
J Biol Chem ; 299(5): 104613, 2023 05.
Article in English | MEDLINE | ID: mdl-36931391

ABSTRACT

Epstein-Barr virus (EBV) is a member of the lymphotropic virus family and is highly correlated with some human malignant tumors. It has been reported that envelope glycoprotein 110 (gp110) plays an essential role in viral fusion, DNA replication, and nucleocapsid assembly of EBV. However, it has not been established whether gp110 is involved in regulating the host's innate immunity. In this study, we found that gp110 inhibits tumor necrosis factor α-mediated NF- κB promoter activity and the downstream production of NF- κB-regulated cytokines under physiological conditions. Using dual-luciferase reporter assays, we showed that gp110 might impede the NF-κB promoter activation downstream of NF-κB transactivational subunit p65. Subsequently, we used coimmunoprecipitation assays to demonstrate that gp110 interacts with p65 during EBV lytic infection, and that the C-terminal cytoplasmic region of gp110 is the key interaction domain with p65. Furthermore, we determined that gp110 can bind to the N-terminal Rel homologous and C-terminal domains of p65. Alternatively, gp110 might not disturb the association of p65 with nontransactivational subunit p50, but we showed it restrains activational phosphorylation (at Ser536) and nuclear translocation of p65, which we also found to be executed by the C-terminal cytoplasmic region of gp110. Altogether, these data suggest that the surface protein gp110 may be a vital component for EBV to antagonize the host's innate immune response, which is also helpful for revealing the infectivity and pathogenesis of EBV.


Subject(s)
Epstein-Barr Virus Infections , NF-kappa B , Humans , NF-kappa B/genetics , NF-kappa B/metabolism , Herpesvirus 4, Human/metabolism , Epstein-Barr Virus Infections/genetics , Transcription Factor RelA/genetics , Transcription Factor RelA/metabolism , Signal Transduction , Protein Transport
4.
Int J Mol Sci ; 25(3)2024 Feb 04.
Article in English | MEDLINE | ID: mdl-38339155

ABSTRACT

Annexins (ANNs) are a structurally conserved protein family present in almost all plants. In the present study, 27 GhANNs were identified in cotton and were unevenly distributed across 14 chromosomes. Transcriptome data and RT-qPCR results revealed that multiple GhANNs respond to at least two abiotic stresses. Similarly, the expression levels of GhANN4 and GhANN11 were significantly upregulated under heat, cold, and drought stress. Using virus-induced gene silencing (VIGS), functional characterization of GhANN4 and GhANN11 revealed that, compared with those of the controls, the leaf wilting of GhANN4-silenced plants was more obvious, and the activities of catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) were lower under NaCl and PEG stress. Moreover, the expression of stress marker genes (GhCBL3, GhDREB2A, GhDREB2C, GhPP2C, GhRD20-2, GhCIPK6, GhNHX1, GhRD20-1, GhSOS1, GhSOS2 and GhSnRK2.6) was significantly downregulated in GhANN4-silenced plants after stress. Under cold stress, the growth of the GHANN11-silenced plants was significantly weaker than that of the control plants, and the activities of POD, SOD, and CAT were also lower. However, compared with those of the control, the elasticity and orthostatic activity of the GhANN11-silenced plants were greater; the POD, SOD, and CAT activities were higher; and the GhDREB2C, GhHSP, and GhSOS2 expression levels were greater under heat stress. These results suggest that different GhANN family members respond differently to different types of abiotic stress.


Subject(s)
Genome, Plant , Plant Proteins , Plant Proteins/genetics , Plant Proteins/metabolism , Transcriptome , Stress, Physiological/genetics , Superoxide Dismutase/metabolism , Gossypium/genetics , Gossypium/metabolism , Gene Expression Regulation, Plant , Phylogeny
5.
Opt Express ; 31(26): 44375-44384, 2023 Dec 18.
Article in English | MEDLINE | ID: mdl-38178510

ABSTRACT

Tunable terahertz (THz) microcavities are crucial for the compact on-chip THz devices, aiming to future cloud-based computing, and artificial-intelligence technologies. However, the solutions to effectively modulate THz microcavities remain elusive. Strong coupling has been widely demonstrated in many configurations at different ambient conditions to date and may serve as a promising tool to modulate THz microcavities. Here, we schematically design a microcavity-plasmon hybrid system, and propose an effective approach to modulating the resonant frequencies of THz microcavities by the microcavity-resonator strong coupling. In this case, we observed the strongly coupling states, where the resultant two-polariton branches exhibit an anti-crossing splitting in the frequency domain, experimentally exhibiting a ∼6.2% frequency modulation to the microcavity compared to the uncoupled case. This work provides an efficient approach to modulating chip-scale THz microcavities, thereby facilitating the development and application of compact THz integrated devices, further empowering the evolution of future information processing and intelligent computing system.

6.
Retina ; 42(8): 1512-1519, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35395659

ABSTRACT

PURPOSE: To explore the effectiveness, safety and psychological impact of foldable capsular vitreous body (FCVB) implantation for complicated retinal detachment caused by severe ocular trauma. METHODS: This was a prospective, single-arm, surgical interventional case series study. A standard 3-port 23-gauge pars plana vitrectomy was performed, and the FCVB was implanted into the vitreous cavity. Observed indicators, including the best-corrected visual acuity, intraocular pressure (IOP), retinal reattachment, complications, and patient satisfaction, were analyzed to evaluate the study. RESULTS: A total of 28 cases (eyes) were enrolled, with a mean follow-up of 16.93 ± 9.67 months and an average age of 51.11 ± 10.14 years, including 22 men (78.57%). The FCVB was successfully implanted, and the retina was reattached in all cases. The postoperative best-corrected visual acuity improved in 7 cases, and remained unchanged in 21 cases ( P > 0.05). The average IOP was 7.01 ± 2.43 mmHg before surgery and 8.54 ± 2.93 mmHg after surgery ( P < 0.05). Complications such as FCVB displacement, endophthalmitis, secondary glaucoma, silicone oil emulsification, and escape did not occur during the follow-up period. Patients with FCVB implantation are highly satisfied. Most patients feel hope, positive, and optimistic about life. CONCLUSION: Foldable capsular vitreous body implantation for complicated retinal detachment caused by severe ocular trauma is effective and safe, and it allows patients to face life positively and optimistically.


Subject(s)
Eye Injuries , Retinal Detachment , Adult , Eye Injuries/complications , Eye Injuries/surgery , Humans , Male , Middle Aged , Prospective Studies , Retinal Detachment/diagnosis , Retinal Detachment/etiology , Retinal Detachment/surgery , Retrospective Studies , Silicone Oils , Vitrectomy , Vitreous Body/surgery
7.
Biochem Biophys Res Commun ; 549: 135-142, 2021 04 16.
Article in English | MEDLINE | ID: mdl-33676181

ABSTRACT

A protein-RNA complex containing the RNA helicase CGH-1 and a germline specific RNA-binding protein CAR-1 is involved in various aspects of function in C. elegans. However, the structural basis for the assembly of this protein complex remains unclear. Here, we elucidate the molecular basis of the recognition of CGH-1 by CAR-1. Additionally, we found that the ATPase activity of CGH-1 is stimulated by NTL-1a MIF4G domain in vitro. Furthermore, we determined the structures of the two RecA-like domains of CGH-1 by X-ray crystallography at resolutions of 1.85 and 2.40 Å, respectively. Structural and biochemical approaches revealed a bipartite interface between CGH-1 RecA2 and the FDF-TFG motif of CAR-1. NMR and structure-based mutations in CGH-1 RecA2 or CAR-1 attenuated or disrupted CGH-1 binding to CAR-1, assessed by ITC and GST-pulldown in vitro. These findings provide insights into a conserved mechanism in the recognition of CGH-1 by CAR-1. Together, our data provide the missing physical links in understanding the assembly and function of CGH-1 and CAR-1 in C. elegans.


Subject(s)
Caenorhabditis elegans Proteins/chemistry , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/enzymology , RNA Nucleotidyltransferases/chemistry , RNA Nucleotidyltransferases/metabolism , RNA-Binding Proteins/metabolism , Adenosine Triphosphatases/chemistry , Adenosine Triphosphatases/metabolism , Amino Acids/chemistry , Animals , Conserved Sequence , Crystallography, X-Ray , Nitrogen Isotopes , Protein Domains , Proton Magnetic Resonance Spectroscopy
8.
Bull Math Biol ; 83(10): 108, 2021 09 08.
Article in English | MEDLINE | ID: mdl-34498148

ABSTRACT

In this paper, we used a generic two-stage population model to derive an adaptive dynamical system for the evolution of reproduction age and studied how this evolution is driven by the harvest of adults. We considered the tradeoffs between maturation rate and fecundity, juvenile mortality, and adult mortality. We analyzed the benefit and cost of faster maturation under each tradeoff that drives the evolution. We found that harvesting adults affects the evolution of maturation by affecting the benefit. For the tradeoff between maturation and juvenile mortality, harvesting adults does not affect the benefit and thus, does not affect optimal maturation strategy. For the other two tradeoffs, harvesting adults affects the benefit through the equilibrium adult/juvenile ratio, which is determined by the density dependence of juveniles. Harvesting adults causes a slower maturation only if it significantly reduces this ratio, which can only happen with very strong adult protection to juveniles. Otherwise, harvesting adults always causes a faster maturation.


Subject(s)
Mathematical Concepts , Models, Biological , Biological Evolution , Fertility , Population Dynamics , Reproduction
9.
Nano Lett ; 20(9): 6636-6643, 2020 Sep 09.
Article in English | MEDLINE | ID: mdl-32786951

ABSTRACT

Lead halide perovskites have emerged as excellent optical gain materials for solution-processable and flexible lasers. Recently, continuous-wave (CW) optically driven lasing was established in perovskite crystals; however, the mechanism of low-threshold operation is still disputed. In this study, CW-pumped lasing from one-dimensional CsPbBr3 nanoribbons (NBs) with a threshold of ∼130 W cm-2 is demonstrated, which can be ascribed to the large refractive index induced by the exciton-polariton (EP) effect. Increasing the temperature reduces the exciton fraction of EPs, which decreases the group and phase refractive indices and inhibits lasing above 100 K. Thermal management, including reducing the NB height to ∼120 ± 60 nm and adopting a high-thermal-conductivity sink, e.g., sapphire, is critical for CW-driven lasing, even at cryogenic temperatures. These results reveal the nature of ultralow-threshold lasing with CsPbBr3 and provide insights into the construction of room-temperature CW and electrically driven perovskite macro/microlasers.

10.
Biol Chem ; 401(2): 309-317, 2020 02 25.
Article in English | MEDLINE | ID: mdl-31665103

ABSTRACT

Pseudorabies virus (PRV) UL2 (pUL2) is a multifunctional protein, which is homologous with herpes simplex virus 1 early protein UL2 (hUL2) and crucial for the viral propagation. Yet, how pUL2 executes its roles in the viral life cycle remain inadequately understood. In order to uncover its effect on the procedure of PRV infection, investigation was performed to examine the subcellular distribution of pUL2 and establish its trafficking mechanism. In the present study, enhanced yellow fluorescent protein or Myc tag fused pUL2 was transiently overexpressed in transfected cells and exhibited an absolutely nuclear accumulation without the existence of other PRV proteins. Additionally, the nuclear trafficking of pUL2 was proved to rely on Ran-, transportin-1, importin ß1, importin α1, α3 and α5. Accordingly, these data will benefit the knowledge of pUL2-mediated biological effects in PRV infection cycle.


Subject(s)
Cell Nucleus/metabolism , Uracil-DNA Glycosidase/metabolism , Viral Proteins/metabolism , Active Transport, Cell Nucleus , Animals , COS Cells , Chlorocebus aethiops , Cloning, Molecular , Uracil-DNA Glycosidase/genetics , Viral Proteins/genetics
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