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1.
Cell ; 185(4): 630-640.e10, 2022 02 17.
Article in English | MEDLINE | ID: mdl-35093192

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic continues worldwide with many variants arising, some of which are variants of concern (VOCs). A recent VOC, omicron (B.1.1.529), which obtains a large number of mutations in the receptor-binding domain (RBD) of the spike protein, has risen to intense scientific and public attention. Here, we studied the binding properties between the human receptor ACE2 (hACE2) and the VOC RBDs and resolved the crystal and cryoelectron microscopy structures of the omicron RBD-hACE2 complex as well as the crystal structure of the delta RBD-hACE2 complex. We found that, unlike alpha, beta, and gamma, omicron RBD binds to hACE2 at a similar affinity to that of the prototype RBD, which might be due to compensation of multiple mutations for both immune escape and transmissibility. The complex structures of omicron RBD-hACE2 and delta RBD-hACE2 reveal the structural basis of how RBD-specific mutations bind to hACE2.


Subject(s)
Angiotensin-Converting Enzyme 2/chemistry , Receptors, Virus/chemistry , SARS-CoV-2/chemistry , Amino Acid Sequence , Cryoelectron Microscopy , Humans , Models, Molecular , Mutation/genetics , Phylogeny , Protein Binding , Protein Domains , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/ultrastructure , Static Electricity , Structural Homology, Protein
2.
Cell ; 185(13): 2265-2278.e14, 2022 06 23.
Article in English | MEDLINE | ID: mdl-35568034

ABSTRACT

Breakthrough infections by SARS-CoV-2 variants become the global challenge for pandemic control. Previously, we developed the protein subunit vaccine ZF2001 based on the dimeric receptor-binding domain (RBD) of prototype SARS-CoV-2. Here, we developed a chimeric RBD-dimer vaccine approach to adapt SARS-CoV-2 variants. A prototype-Beta chimeric RBD-dimer was first designed to adapt the resistant Beta variant. Compared with its homotypic forms, the chimeric vaccine elicited broader sera neutralization of variants and conferred better protection in mice. The protection of the chimeric vaccine was further verified in macaques. This approach was generalized to develop Delta-Omicron chimeric RBD-dimer to adapt the currently prevalent variants. Again, the chimeric vaccine elicited broader sera neutralization of SARS-CoV-2 variants and conferred better protection against challenge by either Delta or Omicron SARS-CoV-2 in mice. The chimeric approach is applicable for rapid updating of immunogens, and our data supported the use of variant-adapted multivalent vaccine against circulating and emerging variants.


Subject(s)
COVID-19 , Vaccines , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Mice , SARS-CoV-2/genetics
3.
Cell ; 182(5): 1271-1283.e16, 2020 09 03.
Article in English | MEDLINE | ID: mdl-32795413

ABSTRACT

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.


Subject(s)
RNA, Messenger/genetics , RNA, Viral/genetics , Vaccines, Synthetic/immunology , Viral Vaccines/immunology , Animals , Antibodies, Neutralizing/immunology , Binding Sites , COVID-19 Vaccines , Chlorocebus aethiops , Coronavirus Infections/genetics , Coronavirus Infections/immunology , Coronavirus Infections/prevention & control , Female , HEK293 Cells , HeLa Cells , Humans , Immunogenicity, Vaccine , Injections, Intramuscular , Macaca fascicularis , Male , Mice , Mice, Inbred ICR , Nanoparticles/chemistry , RNA, Messenger/metabolism , RNA, Viral/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Th1 Cells/immunology , Vaccine Potency , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/genetics , Vero Cells , Viral Vaccines/administration & dosage , Viral Vaccines/genetics
4.
Nat Immunol ; 23(3): 423-430, 2022 03.
Article in English | MEDLINE | ID: mdl-35228696

ABSTRACT

The global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic requires effective therapies against coronavirus disease 2019 (COVID-19), and neutralizing antibodies are a promising therapy. A noncompeting pair of human neutralizing antibodies (B38 and H4) blocking SARS-CoV-2 binding to its receptor, ACE2, have been described previously. Here, we develop bsAb15, a bispecific monoclonal antibody (bsAb) based on B38 and H4. bsAb15 has greater neutralizing efficiency than these parental antibodies, results in less selective pressure and retains neutralizing ability to most SARS-CoV-2 variants of concern (with more potent neutralizing activity against the Delta variant). We also selected for escape mutants of the two parental mAbs, a mAb cocktail and bsAb15, demonstrating that bsAb15 can efficiently neutralize all single-mAb escape mutants. Furthermore, prophylactic and therapeutic application of bsAb15 reduced the viral titer in infected nonhuman primates and human ACE2 transgenic mice. Therefore, this bsAb is a feasible and effective strategy to treat and prevent severe COVID-19.


Subject(s)
Antibodies, Bispecific/immunology , Antibodies, Monoclonal/immunology , Antibodies, Viral/immunology , SARS-CoV-2/immunology , Animals , Antibodies, Bispecific/chemistry , Antibodies, Bispecific/genetics , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/genetics , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/immunology , Antibodies, Viral/chemistry , Antibodies, Viral/genetics , COVID-19/immunology , COVID-19/pathology , COVID-19/prevention & control , COVID-19/virology , Cloning, Molecular , Disease Models, Animal , Dose-Response Relationship, Immunologic , Epitopes , Humans , Macaca mulatta , Mice , Neutralization Tests , Protein Engineering/methods , Structure-Activity Relationship
5.
Cell ; 177(7): 1725-1737.e16, 2019 06 13.
Article in English | MEDLINE | ID: mdl-31080061

ABSTRACT

Mxra8 is a receptor for multiple arthritogenic alphaviruses that cause debilitating acute and chronic musculoskeletal disease in humans. Herein, we present a 2.2 Å resolution X-ray crystal structure of Mxra8 and 4 to 5 Å resolution cryo-electron microscopy reconstructions of Mxra8 bound to chikungunya (CHIKV) virus-like particles and infectious virus. The Mxra8 ectodomain contains two strand-swapped Ig-like domains oriented in a unique disulfide-linked head-to-head arrangement. Mxra8 binds by wedging into a cleft created by two adjacent CHIKV E2-E1 heterodimers in one trimeric spike and engaging a neighboring spike. Two binding modes are observed with the fully mature VLP, with one Mxra8 binding with unique contacts. Only the high-affinity binding mode was observed in the complex with infectious CHIKV, as viral maturation and E3 occupancy appear to influence receptor binding-site usage. Our studies provide insight into how Mxra8 binds CHIKV and creates a path for developing alphavirus entry inhibitors.


Subject(s)
Chikungunya virus/chemistry , Membrane Proteins/chemistry , Viral Envelope Proteins/chemistry , Chikungunya virus/metabolism , Chikungunya virus/ultrastructure , Cryoelectron Microscopy , HEK293 Cells , Humans , Membrane Proteins/metabolism , Protein Domains , Viral Envelope Proteins/metabolism
6.
Development ; 151(17)2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39101673

ABSTRACT

The dorsal aorta (DA) is the first major blood vessel to develop in the embryonic cardiovascular system. Its formation is governed by a coordinated process involving the migration, specification, and arrangement of angioblasts into arterial and venous lineages, a process conserved across species. Although vascular endothelial growth factor a (VEGF-A) is known to drive DA specification and formation, the kinases involved in this process remain ambiguous. Thus, we investigated the role of protein kinase B (Akt) in zebrafish by generating a quadruple mutant (aktΔ/Δ), in which expression and activity of all Akt genes - akt1, -2, -3a and -3b - are strongly decreased. Live imaging of developing aktΔ/Δ DA uncovers early arteriovenous malformations. Single-cell RNA-sequencing analysis of aktΔ/Δ endothelial cells corroborates the impairment of arterial, yet not venous, cell specification. Notably, endothelial specific expression of ligand-independent activation of Notch or constitutively active Akt1 were sufficient to re-establish normal arterial specification in aktΔ/Δ. The Akt loss-of-function mutant unveils that Akt kinase can act upstream of Notch in arterial endothelial cells, and is involved in proper embryonic artery specification. This sheds light on cardiovascular development, revealing a mechanism behind congenital malformations.


Subject(s)
Arteries , Proto-Oncogene Proteins c-akt , Receptors, Notch , Zebrafish Proteins , Zebrafish , Animals , Zebrafish/embryology , Zebrafish/genetics , Zebrafish/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-akt/genetics , Zebrafish Proteins/metabolism , Zebrafish Proteins/genetics , Receptors, Notch/metabolism , Receptors, Notch/genetics , Arteries/embryology , Arteries/metabolism , Gene Expression Regulation, Developmental , Endothelial Cells/metabolism , Signal Transduction , Mutation/genetics , Embryo, Nonmammalian/metabolism , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor A/genetics
7.
Immunity ; 48(3): 487-499.e5, 2018 03 20.
Article in English | MEDLINE | ID: mdl-29525521

ABSTRACT

Although interferon-induced proteins with tetratricopeptide repeats (IFIT proteins) inhibit infection of many viruses by recognizing their RNA, the regulatory mechanisms involved remain unclear. Here we report a crystal structure of cap 0 (m7GpppN) RNA bound to human IFIT1 in complex with the C-terminal domain of human IFIT3. Structural, biochemical, and genetic studies suggest that IFIT3 binding to IFIT1 has dual regulatory functions: (1) extending the half-life of IFIT1 and thereby increasing its steady-state amounts in cells; and (2) allosterically regulating the IFIT1 RNA-binding channel, thereby enhancing the specificity of recognition for cap 0 but not cap 1 (m7GpppNm) or 5'-ppp RNA. Mouse Ifit3 lacks this key C-terminal domain and does not bind mouse Ifit1. The IFIT3 interaction with IFIT1 is important for restricting infection of viruses lacking 2'-O methylation in their RNA cap structures. Our experiments establish differences in the regulation of IFIT1 orthologs and define targets for modulation of human IFIT protein activity.


Subject(s)
Carrier Proteins/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , RNA-Binding Proteins/metabolism , Adaptor Proteins, Signal Transducing , Animals , Carrier Proteins/chemistry , Carrier Proteins/genetics , Gene Expression Regulation , Host-Pathogen Interactions/genetics , Humans , Intracellular Signaling Peptides and Proteins/chemistry , Intracellular Signaling Peptides and Proteins/genetics , Methylation , Mice , Models, Molecular , Molecular Conformation , Protein Binding , Protein Interaction Domains and Motifs , Protein Stability , RNA/chemistry , RNA/genetics , RNA/metabolism , RNA-Binding Proteins/chemistry , RNA-Binding Proteins/genetics , Species Specificity , Structure-Activity Relationship
8.
PLoS Genet ; 20(2): e1011163, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38377137

ABSTRACT

Neonicotinoid insecticides, which target insect nicotinic acetylcholine receptors (nAChRs), have been widely and intensively used to control the whitefly, Bemisia tabaci, a highly damaging, globally distributed, crop pest. This has inevitably led to the emergence of populations with resistance to neonicotinoids. However, to date, there have been no reports of target-site resistance involving mutation of B. tabaci nAChR genes. Here we characterize the nAChR subunit gene family of B. tabaci and identify dual mutations (A58T&R79E) in one of these genes (BTß1) that confer resistance to multiple neonicotinoids. Transgenic D. melanogaster, where the native nAChR Dß1 was replaced with BTß1A58T&R79E, were significantly more resistant to neonicotinoids than flies where Dß1 were replaced with the wildtype BTß1 sequence, demonstrating the causal role of the mutations in resistance. The two mutations identified in this study replace two amino acids that are highly conserved in >200 insect species. Three-dimensional modelling suggests a molecular mechanism for this resistance, whereby A58T forms a hydrogen bond with the R79E side chain, which positions its negatively-charged carboxylate group to electrostatically repulse a neonicotinoid at the orthosteric site. Together these findings describe the first case of target-site resistance to neonicotinoids in B. tabaci and provide insight into the molecular determinants of neonicotinoid binding and selectivity.


Subject(s)
Hemiptera , Insecticides , Receptors, Nicotinic , Animals , Receptors, Nicotinic/genetics , Insecticides/pharmacology , Hemiptera/genetics , Drosophila melanogaster , Neonicotinoids/pharmacology , Mutation
9.
Pharmacol Rev ; 76(5): 846-895, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38866561

ABSTRACT

Cardiometabolic diseases (CMDs) are major contributors to global mortality, emphasizing the critical need for novel therapeutic interventions. Hydrogen sulfide (H2S) has garnered enormous attention as a significant gasotransmitter with various physiological, pathophysiological, and pharmacological impacts within mammalian cardiometabolic systems. In addition to its roles in attenuating oxidative stress and inflammatory response, burgeoning research emphasizes the significance of H2S in regulating proteins via persulfidation, a well known modification intricately associated with the pathogenesis of CMDs. This review seeks to investigate recent updates on the physiological actions of endogenous H2S and the pharmacological roles of various H2S donors in addressing diverse aspects of CMDs across cellular, animal, and clinical studies. Of note, advanced methodologies, including multiomics, intestinal microflora analysis, organoid, and single-cell sequencing techniques, are gaining traction due to their ability to offer comprehensive insights into biomedical research. These emerging approaches hold promise in characterizing the pharmacological roles of H2S in health and diseases. We will critically assess the current literature to clarify the roles of H2S in diseases while also delineating the opportunities and challenges they present in H2S-based pharmacotherapy for CMDs. SIGNIFICANCE STATEMENT: This comprehensive review covers recent developments in H2S biology and pharmacology in cardiometabolic diseases CMDs. Endogenous H2S and its donors show great promise for the management of CMDs by regulating numerous proteins and signaling pathways. The emergence of new technologies will considerably advance the pharmacological research and clinical translation of H2S.


Subject(s)
Cardiovascular Diseases , Hydrogen Sulfide , Hydrogen Sulfide/metabolism , Humans , Animals , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/metabolism , Metabolic Diseases/drug therapy , Metabolic Diseases/metabolism , Gasotransmitters/metabolism
10.
J Immunol ; 213(7): 1008-1022, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39194407

ABSTRACT

The functions of the natural dsRNA sensors TLR3 (TRIF) and RIG-I (MAVS) are crucial during viral challenge and have not been accurately clarified in adaptive immune responses to rotavirus (RV) infection. In this study, we found that RV infection caused severe pathological damage to the small intestine of TLR3-/- and TRIF-/- mice. Our data found that dendritic cells from TLR3-/- and TRIF-/- mice had impaired Ag presentation to the RV and attenuated initiation of T cells upon viral infection. These attenuated functions resulted in impaired CD4+ T and CD8+ T function in mice lacking TLR3-TRIF signaling postinfection. Additionally, attenuated proliferative capacity of T cells from TLR3-/- and TRIF-/- mice was observed. Subsequently, we observed a significant reduction in the absolute number of memory T cells in the spleen and mesenteric lymph node (MLN) of TRIF-/- recipient mice following RV infection in a bone marrow chimeric model. Furthermore, there was reduced migration of type 2 classical dendritic cells from the intestine to MLNs after RV infection in TLR3-/- and TRIF-/- mice. Notably, RV infection resulted in attenuated killing of spleen and MLN tissues in TRIF-/- and MAVS-/- mice. Finally, we demonstrated that RV infection promoted apoptosis of CD8+ T cells in TRIF-/- and TLR3-/-MAVS-/- mice. Taken together, our findings highlight an important mechanism of TLR3 signaling through TRIF in mucosal T cell responses to RV and lay the foundation for the development of a novel vaccine.


Subject(s)
Adaptor Proteins, Signal Transducing , Adaptor Proteins, Vesicular Transport , Dendritic Cells , Mice, Knockout , Rotavirus Infections , Rotavirus , Signal Transduction , Toll-Like Receptor 3 , Animals , Toll-Like Receptor 3/immunology , Mice , Rotavirus Infections/immunology , Signal Transduction/immunology , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/immunology , Rotavirus/immunology , Dendritic Cells/immunology , Mice, Inbred C57BL , Intestinal Mucosa/immunology , CD8-Positive T-Lymphocytes/immunology , Immunity, Mucosal , Antigen Presentation/immunology
11.
Nucleic Acids Res ; 52(3): 1512-1521, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38164993

ABSTRACT

The field of synthetic biology and biosystems engineering increasingly acknowledges the need for a holistic design approach that incorporates circuit-host interactions into the design process. Engineered circuits are not isolated entities but inherently entwined with the dynamic host environment. One such circuit-host interaction, 'growth feedback', results when modifications in host growth patterns influence the operation of gene circuits. The growth-mediated effects can range from growth-dependent elevation in protein/mRNA dilution rate to changes in resource reallocation within the cell, which can lead to complete functional collapse in complex circuits. To achieve robust circuit performance, synthetic biologists employ a variety of control mechanisms to stabilize and insulate circuit behavior against growth changes. Here we propose a simple strategy by incorporating one repressive edge in a growth-sensitive bistable circuit. Through both simulation and in vitro experimentation, we demonstrate how this additional repressive node stabilizes protein levels and increases the robustness of a bistable circuit in response to growth feedback. We propose the incorporation of repressive links in gene circuits as a control strategy for desensitizing gene circuits against growth fluctuations.


Subject(s)
Gene Regulatory Networks , Synthetic Biology , Computer Simulation , Feedback , Proteins/genetics , Synthetic Biology/methods
12.
Proc Natl Acad Sci U S A ; 120(40): e2303878120, 2023 10 03.
Article in English | MEDLINE | ID: mdl-37748061

ABSTRACT

AMPA receptors (AMPARs) play a critical role in synaptic plasticity and learning and memory, and dysfunction or dysregulation of AMPARs could lead to various neurological and psychiatric disorders, such as Alzheimer's disease (AD). However, the dynamics and/or longitudinal changes of AMPARs in vivo during AD pathogenesis remain elusive. Here, employing 5xFAD SEP-GluA1 KI mice, we investigated endogenous AMPA receptor dynamics in a whisker deflection-associated Go/No-go learning paradigm. We found a significant increase in synaptosomal AMPA receptor subunits GluA1 in WT mice after learning, while no such changes were detected in 7-mo-old 5xFAD mice. Daily training led to an increase in endogenous spine surface GluA1 in Control mice, while this increase was absent in 5xFAD-KI mice which correlates with its learning defects in Go/No-go paradigm. Furthermore, we demonstrated that the onset of abnormal AMPAR dynamics corresponds temporally with microglia and astrocyte overactivation. Our results have shown that impairments in endogenous AMPA receptor dynamics play an important role in learning deficits in 5xFAD mice and AD pathogenesis.


Subject(s)
Alzheimer Disease , Receptors, AMPA , Humans , Animals , Mice , Learning , Astrocytes , Microglia
13.
Proc Natl Acad Sci U S A ; 120(52): e2314193120, 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38109549

ABSTRACT

Currently, monoclonal antibodies (MAbs) targeting the SARS-CoV-2 receptor binding domain (RBD) of spike (S) protein are classified into seven classes based on their binding epitopes. However, most of these antibodies are seriously impaired by SARS-CoV-2 Omicron and its subvariants, especially the recent BQ.1.1, XBB and its derivatives. Identification of broadly neutralizing MAbs against currently circulating variants is imperative. In this study, we identified a "breathing" cryptic epitope in the S protein, named as RBD-8. Two human MAbs, BIOLS56 and IMCAS74, were isolated recognizing this epitope with broad neutralization abilities against tested sarbecoviruses, including SARS-CoV, pangolin-origin coronaviruses, and all the SARS-CoV-2 variants tested (Omicron BA.4/BA.5, BQ.1.1, and XBB subvariants). Searching through the literature, some more RBD-8 MAbs were defined. More importantly, BIOLS56 rescues the immune-evaded antibody, RBD-5 MAb IMCAS-L4.65, by making a bispecific MAb, to neutralize BQ.1 and BQ.1.1, thereby producing an MAb to cover all the currently circulating Omicron subvariants. Structural analysis reveals that the neutralization effect of RBD-8 antibodies depends on the extent of epitope exposure, which is affected by the angle of antibody binding and the number of up-RBDs induced by angiotensin-converting enzyme 2 binding. This cryptic epitope which recognizes non- receptor binding motif (non-RBM) provides guidance for the development of universal therapeutic antibodies and vaccines against COVID-19.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , COVID-19 Vaccines , Antibodies, Monoclonal , Epitopes , Antibodies, Neutralizing , Antibodies, Viral , Spike Glycoprotein, Coronavirus
14.
Plant J ; 118(3): 717-730, 2024 May.
Article in English | MEDLINE | ID: mdl-38213282

ABSTRACT

Cryptotaenia japonica, a traditional medicinal and edible vegetable crops, is well-known for its attractive flavors and health care functions. As a member of the Apiaceae family, the evolutionary trajectory and biological properties of C. japonica are not clearly understood. Here, we first reported a high-quality genome of C. japonica with a total length of 427 Mb and N50 length 50.76 Mb, was anchored into 10 chromosomes, which confirmed by chromosome (cytogenetic) analysis. Comparative genomic analysis revealed C. japonica exhibited low genetic redundancy, contained a higher percentage of single-cope gene families. The homoeologous blocks, Ks, and collinearity were analyzed among Apiaceae species contributed to the evidence that C. japonica lacked recent species-specific WGD. Through comparative genomic and transcriptomic analyses of Apiaceae species, we revealed the genetic basis of the production of anthocyanins. Several structural genes encoding enzymes and transcription factor genes of the anthocyanin biosynthesis pathway in different species were also identified. The CjANSa, CjDFRb, and CjF3H gene might be the target of Cjaponica_2.2062 (bHLH) and Cjaponica_1.3743 (MYB). Our findings provided a high-quality reference genome of C. japonica and offered new insights into Apiaceae evolution and biology.


Subject(s)
Anthocyanins , Apiaceae , Genome, Plant , Genomics , Anthocyanins/biosynthesis , Anthocyanins/genetics , Anthocyanins/metabolism , Genome, Plant/genetics , Apiaceae/genetics , Apiaceae/metabolism , Phylogeny , Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant , Transcription Factors/genetics , Transcription Factors/metabolism , Chromosomes, Plant/genetics
15.
EMBO J ; 40(5): e104267, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33491217

ABSTRACT

Impairments in social relationships and awareness are features observed in autism spectrum disorders (ASDs). However, the underlying mechanisms remain poorly understood. Shank2 is a high-confidence ASD candidate gene and localizes primarily to postsynaptic densities (PSDs) of excitatory synapses in the central nervous system (CNS). We show here that loss of Shank2 in mice leads to a lack of social attachment and bonding behavior towards pubs independent of hormonal, cognitive, or sensitive deficits. Shank2-/- mice display functional changes in nuclei of the social attachment circuit that were most prominent in the medial preoptic area (MPOA) of the hypothalamus. Selective enhancement of MPOA activity by DREADD technology re-established social bonding behavior in Shank2-/- mice, providing evidence that the identified circuit might be crucial for explaining how social deficits in ASD can arise.


Subject(s)
Autistic Disorder/drug therapy , Disease Models, Animal , Interpersonal Relations , Maternal Behavior/drug effects , Nerve Tissue Proteins/physiology , Piperazines/pharmacology , Preoptic Area/drug effects , Animals , Autistic Disorder/etiology , Autistic Disorder/metabolism , Autistic Disorder/pathology , Female , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Preoptic Area/metabolism , Preoptic Area/pathology , Synapses
16.
J Virol ; 98(5): e0195723, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38557247

ABSTRACT

Zoonotic coronaviruses pose a continuous threat to human health, with newly identified bat-borne viruses like swine acute diarrhea syndrome coronavirus (SADS-CoV) causing high mortality in piglets. In vitro studies indicate that SADS-CoV can infect cell lines from diverse species, including humans, highlighting its potential risk to human health. However, the lack of tools to study viral entry, along with the absence of vaccines or antiviral therapies, perpetuates this threat. To address this, we engineered an infectious molecular clone of Vesicular Stomatitis Virus (VSV), replacing its native glycoprotein (G) with SADS-CoV spike (S) and inserting a Venus reporter at the 3' leader region to generate a replication-competent rVSV-Venus-SADS S virus. Serial passages of rVSV-Venus-SADS S led to the identification of an 11-amino-acid truncation in the cytoplasmic tail of the S protein, which allowed more efficient viral propagation due to increased cell membrane anchoring of the S protein. The S protein was integrated into rVSV-Venus-SADS SΔ11 particles, susceptible to neutralization by sera from SADS-CoV S1 protein-immunized rabbits. Additionally, we found that TMPRSS2 promotes SADS-CoV spike-mediated cell entry. Furthermore, we assessed the serum-neutralizing ability of mice vaccinated with rVSV-Venus-SADS SΔ11 using a prime-boost immunization strategy, revealing effective neutralizing antibodies against SADS-CoV infection. In conclusion, we have developed a safe and practical tool for studying SADS-CoV entry and exploring the potential of a recombinant VSV-vectored SADS-CoV vaccine.IMPORTANCEZoonotic coronaviruses, like swine acute diarrhea syndrome coronavirus (SADS-CoV), pose a continual threat to human and animal health. To combat this, we engineered a safe and efficient tool by modifying the Vesicular Stomatitis Virus (VSV), creating a replication-competent rVSV-Venus-SADS S virus. Through serial passages, we optimized the virus for enhanced membrane anchoring, a key factor in viral propagation. This modified virus, rVSV-Venus-SADS SΔ11, proved susceptible to neutralization, opening avenues for potential vaccines. Additionally, our study revealed the role of TMPRSS2 in SADS-CoV entry. Mice vaccinated with rVSV-Venus-SADS SΔ11 developed potent neutralizing antibodies against SADS-CoV. In conclusion, our work presents a secure and practical tool for studying SADS-CoV entry and explores the promise of a recombinant VSV-vectored SADS-CoV vaccine.


Subject(s)
Alphacoronavirus , Virus Internalization , Virus Replication , Animals , Humans , Mice , Rabbits , Alphacoronavirus/genetics , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme 2/genetics , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Cell Line , Chlorocebus aethiops , Coronavirus Infections/virology , Coronavirus Infections/prevention & control , HEK293 Cells , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism , Serine Endopeptidases/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Swine , Vero Cells , Vesicular stomatitis Indiana virus/genetics , Vesiculovirus/genetics , Viral Vaccines/immunology , Viral Vaccines/genetics
17.
J Virol ; 98(2): e0195423, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38289102

ABSTRACT

During the life cycle of mosquito-borne flaviviruses, substantial subgenomic flaviviral RNA (sfRNA) is produced via incomplete degradation of viral genomic RNA by host XRN1. Zika virus (ZIKV) sfRNA has been detected in mosquito and mammalian somatic cells. Human neural progenitor cells (hNPCs) in the developing brain are the major target cells of ZIKV, and antiviral RNA interference (RNAi) plays a critical role in hNPCs. However, whether ZIKV sfRNA was produced in ZIKV-infected hNPCs as well as its function remains not known. In this study, we demonstrate that abundant sfRNA was produced in ZIKV-infected hNPCs. RNA pulldown and mass spectrum assays showed ZIKV sfRNA interacted with host proteins RHA and PACT, both of which are RNA-induced silencing complex (RISC) components. Functionally, ZIKV sfRNA can antagonize RNAi by outcompeting small interfering RNAs (siRNAs) in binding to RHA and PACT. Furthermore, the 3' stem loop (3'SL) of sfRNA was responsible for RISC components binding and RNAi inhibition, and 3'SL can enhance the replication of a viral suppressor of RNAi (VSR)-deficient virus in a RHA- and PACT-dependent manner. More importantly, the ability of binding to RISC components is conversed among multiple flaviviral 3'SLs. Together, our results identified flavivirus 3'SL as a potent VSR in RNA format, highlighting the complexity in virus-host interaction during flavivirus infection.IMPORTANCEZika virus (ZIKV) infection mainly targets human neural progenitor cells (hNPCs) and induces cell death and dysregulated cell-cycle progression, leading to microcephaly and other central nervous system abnormalities. RNA interference (RNAi) plays critical roles during ZIKV infections in hNPCs, and ZIKV has evolved to encode specific viral proteins to antagonize RNAi. Herein, we first show that abundant sfRNA was produced in ZIKV-infected hNPCs in a similar pattern to that in other cells. Importantly, ZIKV sfRNA acts as a potent viral suppressor of RNAi (VSR) by competing with siRNAs for binding RISC components, RHA and PACT. The 3'SL of sfRNA is responsible for binding RISC components, which is a conserved feature among mosquito-borne flaviviruses. As most known VSRs are viral proteins, our findings highlight the importance of viral non-coding RNAs during the antagonism of host RNAi-based antiviral innate immunity.


Subject(s)
Zika Virus Infection , Zika Virus , Animals , Humans , Mammals/genetics , RNA Interference , RNA, Small Interfering/genetics , RNA, Viral/genetics , RNA, Viral/metabolism , RNA-Induced Silencing Complex/metabolism , Subgenomic RNA , Viral Proteins/metabolism , Virus Replication , Zika Virus/physiology , Zika Virus Infection/immunology , Zika Virus Infection/virology
18.
Nat Mater ; 23(9): 1208-1213, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38641696

ABSTRACT

Symmetry breaking in quantum materials is of great importance and can lead to non-reciprocal charge transport. Topological insulators provide a unique platform to study non-reciprocal charge transport due to their surface states, especially quantum Hall states under an external magnetic field. Here we report the observation of non-reciprocal charge transport mediated by quantum Hall states in devices composed of the intrinsic topological insulator Sn-Bi1.1Sb0.9Te2S, which is attributed to asymmetric scattering between quantum Hall states and Dirac surface states. A giant non-reciprocal coefficient of up to 2.26 × 105 A-1 is found. Our work not only reveals the properties of non-reciprocal charge transport of quantum Hall states in topological insulators but also paves the way for future electronic devices.

19.
Hepatology ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38985984

ABSTRACT

BACKGROUND AND AIMS: An imbalance in lipid metabolism is the main cause of NAFLD. While the pathogenesis of lipid accumulation mediated by extrahepatic regulators has been extensively studied, the intrahepatic regulators modulating lipid homeostasis remain unclear. Previous studies have shown that systemic administration of IL-22 protects against NAFLD; however, the role of IL-22/IL22RA1 signaling in modulating hepatic lipid metabolism remains uncertain. APPROACH AND RESULTS: This study shows that hepatic IL22RA1 is vital in hepatic lipid regulation. IL22RA1 is downregulated in palmitic acid-treated mouse primary hepatocytes, as well as in the livers of NAFLD model mice and patients. Hepatocyte-specific Il22ra1 knockout mice display diet-induced hepatic steatosis, insulin resistance, impaired glucose tolerance, increased inflammation, and fibrosis compared with flox/flox mice. This is attributed to increased lipogenesis mediated by the accumulation of hepatic oxysterols, particularly 3 beta-hydroxy-5-cholestenoic acid (3ß HCA). Mechanistically, hepatic IL22RA1 deficiency facilitates 3ß HCA deposition through the activating transcription factor 3/oxysterol 7 alpha-hydroxylase axis. Notably, 3ß HCA facilitates lipogenesis in mouse primary hepatocytes and human liver organoids by activating liver X receptor-alpha signaling, but IL-22 treatment attenuates this effect. Additionally, restoring oxysterol 7 alpha-hydroxylase or silencing hepatic activating transcription factor 3 reduces both hepatic 3ß HCA and lipid contents in hepatocyte-specific Il22ra1 knockout mice. CONCLUSIONS: These findings indicate that IL22RA1 plays a crucial role in maintaining hepatic lipid homeostasis in an activating transcription factor 3/oxysterol 7 alpha-hydroxylase-dependent manner and establish a link between 3ß HCA and hepatic lipid homeostasis.

20.
FASEB J ; 38(17): e23861, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39247969

ABSTRACT

Recently, amyloid-ß oligomers (AßOs) have been studied as the primary pathogenic substances in Alzheimer's disease (AD). Our previous study revealed that the Aß expression level is closely related to ARC progression. Here, we demonstrated that the accumulation of AßOs in the lens epithelium of age-related cataract (ARC) patients increased during ARC progression and that this alteration was consistent with the changes in mitochondrial function, oxidative stress, and cellular apoptosis. In vitro, human lens epithelial cells (HLECs) treated with AßOs exhibited Ca2+ dyshomeostasis, impaired mitochondrial function, elevated oxidative stress levels, and increased apoptosis. Moreover, the proapoptotic effect of AßOs was alleviated after the uptake of mitochondrial Ca2+ was inhibited. These results establish that AßOs may promote HLEC apoptosis by inducing mitochondrial Ca2+ overload, thus preliminarily revealing the possible association between the accumulation of AßOs and other pathological processes in ARC.


Subject(s)
Amyloid beta-Peptides , Apoptosis , Cataract , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Aging/metabolism , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Calcium/metabolism , Cataract/metabolism , Cataract/pathology , Cells, Cultured , Epithelial Cells/metabolism , Lens, Crystalline/metabolism , Mitochondria/metabolism , Oxidative Stress
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