Biology subjects

Xu, Z.

Publications and source records attributed to Xu, Z..

At least 379 records · Page 21Linked to original sources

bioRxiv2021

Pentameric assembly of the Kv2.1 tetramerization domain.

The Kv family of voltage-gated potassium channels regulate neuronal excitability. The biophysical characteristic of Kv channels can be matched to the needs of different neurons by forming homotetrameric or heterotetrameric channels within one of four subfamilies. The cytoplasmic tetramerization (T1) domain plays a major role in dictating the compatibility of different Kv subunits. The only Kv subfamily missing a representative structure of the T1 domain is the Kv2 family. We used X-ray crystallography to solve the structure of the human Kv2.1 T1 domain. The structure is similar to other T1 domains but surprisingly formed a pentamer instead of a tetramer. In solution the Kv2.1 T1 domain also formed a pentamer as determined with in-line SEC-MALS-SAXS and negative stain EM. The Kv2.1 T1-T1 interface involves electrostatic interactions including a salt bridge formed by the negative charges in a previously described CDD motif, and inter-subunit coordination of zinc. We show that zinc binding is important for stability. In conclusion, the Kv2.1 T1 domain behaves differently from the other Kv T1 domains which may reflect the versatility of Kv2.1, the only Kv subfamily that can assemble with the regulatory KvS subunits and scaffold ER-plasma membrane contacts.

biochemistry↗

bioRxiv2021

Screening for axon regeneration promoting compounds with human iPSC-derived motor neurons

CNS neurons do not regenerate after injury, leading to permanent functional deficits. Although sensory and motor neuron axons do regrow after peripheral nerve injury, functional outcome is limited due to the incomplete and slow regrowth. The lack of human-relevant assays suitable for large-scale drug screens has limited neuro-repair therapy discovery. To address this we developed a phenotypic screening strategy using human induced pluripotent stem cell-derived motor neurons to identify axon-regeneration promoting compounds and targets. The screens involve both re-plating human motor neurons on chondroitin sulfate proteoglycans and measuring regeneration responses to laser axotomy in spot cultures, and from them we identified multiple hits that promote injured axon regrowth. The top hit blebbistatin, a non-muscle myosin II inhibitor, accelerated axon regeneration and functional recovery after sciatic nerve injury in vivo. Human "injury in a dish" assays are suitable, therefore, to screen for therapeutic interventions that can induce or accelerate axon regeneration.

neuroscience↗

bioRxiv2021

Emergence of an adaptive epigenetic cell state in human bladder urothelial carcinoma evolution

Intratumor heterogeneity (ITH) of bladder cancer (BLCA) facilitates therapy resistance and immune evasion to affect clinical prognosis directly. However, the molecular and cellular mechanism generating ITH in BLCA remains elusive. Here we show that a TM4SF1-positive cancer subpopulation (TPCS) drives ITH diversification in BLCA. By extensive profiling of the epigenome and transcriptome of BLCA from 79 donors across all stages, we elucidated the evolution trajectories of luminal and basal BLCA. TPCS emerges from the basal trajectory and shows extensive transcriptional plasticity with a distinct epigenomic landscape. Clinically, TPCS were enriched in advanced stage patients and associated with poor prognosis. Our results showed how cancer adapts to its environment by adopting a stem cell-like epigenomic landscape.

cancer biology↗

bioRxiv2021

Quorum sensing signal autoinducer-2 inhibits sporulation of Bacillus by interacting with RapC and functions across species

Collective behavior of bacteria is regulated by quorum sensing (QS). Bacterial cells sense the density of the population and induce corresponding traits and developmental processes. Autoinducer-2 (AI-2) is a common QS signal that regulates behavior of both Gram-positive and Gram-negative bacteria. In spite of the plethora of processes described to be influenced by AI-2 in diverse Gram-negative bacteria, the AI-2-regulated processes in Bacilli are relatively unexplored. Previously, we demonstrated that AI-2 regulates root colonization of Bacillus velezensis SQR9, a well-studied plant beneficial rhizobacterium. Here, we describe a novel function for AI-2 in B. velezensis SQR9 related to development of dormant spores. AI-2 inhibited the initiation of spore development throught the phosphatase RapC and the DNA binding regulator ComA. Using mutant strains and protein-protein interaction studies, we demonstrate that AI-2 interacts with RapC to stimulate its binding to ComA and therefore inactive ComA. We further demonstrate that ComA is essential for Spo0A-regulated sporulation in B. velezensis SQR9. Finally, the AI-2 molecule could be shared cross species for inhibiting Bacillus sporulation. Our study revealed a novel function and regulation mechanism of AI-2 in sporulation inhibition of Bacilli that overall suggests sporulation to be a population-level decision process in Bacilli rather than just a individual cell behavior. Author summaryQuorum sensing (QS) regulates many bacterial social behavior. Bacteria cells could moniter and respond cell density by sensing the self produced QS signals. While most QS signals are unique for either Gram-positive or Gram-negative bacteria, autoinducer-2 (AI-2) is a QS signal that could produced by both bacteria groups. However, knowledge of the mechanism of AI-2 affecting bacterial behavior is poorly understood. Here, we found AI-2 inhibite Bacillus velezensis SQR9 sporulation, a generally known bacterial individual behavior. We further revealed the mechanism of AI-2 influencing sporulation of B. velezensis SQR9 was dependent on RapC and ComA. AI-2 interacts with RapC to stimulate its binding to ComA and therefore inactive ComA, and then inhibited the Spo0A-regulated sporulation. Interestingly, we show B. velezensis SQR9 could also sense the AI-2 produced by other bacteria and reduce their own sporulation. Taken together we discovered the novel function of AI-2 in sporulation, which will expand the significance of QS signal that they regulate not only social behavior but also individual behavior of bacteria.

microbiology↗

bioRxiv2021

OsMADS58 stabilizes gene regulatory circuits during rice stamen development

Rice (Oryza sativa) OsMADS58 is a C-class MADS box protein, and characterization of a transposon insertion mutant osmads58 suggested that OsMADS58 plays a role in stamen development. However, as no null mutation has been obtained, its role has remained unclear. Here, we report that the CRISPR knockout mutant osmads58 exhibits complex altered phenotypes, including anomalous diploid germ cell differentiation, aberrant meiosis, and delayed tapetum degeneration. This CRISPR mutant line exhibited stronger changes in expression of OsMADS58 target genes compared with the osmads58 dSpm (transposon insertion) line, along with changes in multiple pathways related to early stamen development. Notably, transcriptional regulatory circuits in young panicles covering the stamen at stages 4-6 were substantially altered in the CRISPR line compared to the dSpm line. These findings strongly suggest that the pleiotropic effects of OsMADS58 on stamen development derive from a potential role in stabilizing gene regulatory circuits during early stamen development. Thus, this work opens new avenues for viewing and deciphering the regulatory mechanisms of early stamen development from a network perspective.

plant biology↗

bioRxiv2021

The Polo kinase Cdc5 is regulated at multiple levels in the adaptation response to telomere dysfunction

Telomere dysfunction activates the DNA damage checkpoint to induce a cell cycle arrest. After an extended period of time, however, cells can bypass the arrest and undergo cell division despite the persistence of the initial damage, a process called adaptation to DNA damage. The Polo kinase Cdc5 in Saccharomyces cerevisiae is essential for adaptation and for many other cell-cycle processes. How the regulation of Cdc5 in response to telomere dysfunction relates to adaptation is not clear. Here, we report that Cdc5 protein level decreases after telomere dysfunction in a Mec1-, Rad53- and Ndd1-dependent manner. This regulation of Cdc5 is important to maintain long-term cell cycle arrest but not for the initial checkpoint arrest. We find that both Cdc5 and the adaptation-deficient mutant protein Cdc5-ad are heavily phosphorylated and several phosphorylation sites modulate adaptation efficiency. The PP2A phosphatases are involved in Cdc5-ad phosphorylation status and contribute to adaptation mechanisms. We finally propose that Cdc5 orchestrates multiple cell cycle pathways to promote adaptation.

genetics↗

bioRxiv2021

Annulment of antagonism shifts properties that are beneficial to plants in two-member consortia of Bacillus velezensis

Bacillus spp. strains that are beneficial to plants are widely used in commercial biofertilizers and biocontrol agents for sustainable agriculture. Generally, functional Bacillus strains are applied as single strain communities since the principles of synthetic microbial consortia constructed with Bacillus strains remain largely unclear. Here, we demonstrated that the mutual compatibility directly affects the survival and function of two-member consortia composed of B. velezensis SQR9 and FZB42 in the rhizosphere. A mutation in the global regulator Spo0A of SQR9 markedly reduced the boundary phenotype with wild-type FZB42, and the combined use of the SQR9{triangleup}spo0A mutant and FZB42 improved biofilm formation, root colonization and the production of secondary metabolites that are beneficial to plants. We further confirmed the correlation between the swarm discrimination phenotype between the two consortia members and the effects that are beneficial to plants in a greenhouse experiment. Our results provide evidence that social interactions among bacteria could be an influencing factor in achieving a desired community-level function. IMPORTANCEBacillus velezensis is one of the most widely applied bacteria in biofertilizers in China and Europe. Additionally, the molecular mechanisms of plant growth promotion and disease suppression by representative model strains are well established, such as B. velezensis SQR9 and FZB42. However, it remains extremely challenging to design efficient consortia based on these model strains. Here, we showed that swarm discrimination phenotype is one of the major determinants affects the performance of two-member Bacillus consortia in vitro and in the rhizosphere. Deletion in global regulatory gene spo0A of SQR9 reduced the strength of boundary formation with FZB42, result in the improved plant growth promotion performance of dual consortium. This knowledge provides new insights into efficient probiotics consortia design in Bacillus.

microbiology↗

bioRxiv2021

Alterations in connectome dynamics in autism spectrum disorder: A harmonized mega- and meta-analysis study using the ABIDE dataset

BACKGROUNDNeuroimaging studies have reported functional connectome aberrancies in autism spectrum disorder (ASD). However, the time-varying patterns of connectome topology in ASD individuals and the connection between these patterns and gene expression profiles remain unknown. METHODSTo investigate case-control differences in dynamic connectome topology, we conducted mega- and meta-analyses of resting-state functional magnetic resonance imaging data of 939 participants (440 ASD patients and 499 healthy controls, all males) from 18 independent sites, selected from the ABIDE (Autism Brain Imaging Data Exchange) dataset. Functional data was preprocessed and analyzed using harmonized protocols, and brain module dynamics was assessed using a multilayer network model. We further leveraged postmortem brain-wide gene expression data to identify transcriptomic signatures associated with ASD-related alterations in brain dynamics. RESULTSCompared to healthy controls, ASD individuals exhibited a higher global mean and lower standard deviation of whole-brain module dynamics, indicating an unstable and less regionally differentiated pattern. More specifically, ASD individuals showed higher module switching, primarily in the medial prefrontal cortex, posterior cingulate gyrus, and angular gyrus, and lower switching in the visual regions. These alterations in brain dynamics were predictive of social impairments in ASD individuals and were linked with expression profiles of genes primarily involved in the regulation of neurotransmitter transport and secretion, as well as with previously identified autism-related genes. CONCLUSIONSThis study is the first to identify consistent alterations in brain network dynamics in ASD and the transcriptomic signatures related to those alterations, furthering insights into the biological basis behind this disorder.

neuroscience↗

bioRxiv2021

A unique genomic island-governed cannibalism in Bacillus enhanced biofilm formation through a novel regulation mechanism

Cannibalism is a differentiation strategy and social multicellular behavior in biofilms. The novel factors and mechanisms to trigger the bacterial cannibalism remain scarce. Here, we report a novel bacillunoic acids-mediated strategy for manipulating cannibalism in Bacillus velezensis SQR9 biofilm formation. A subfraction of cells differentiate into cannibals that secrete toxic bacillunoic acids to lyse a fraction of their sensitive siblings, and the released nutrients enhance biofilm formation. Meanwhile, the self-immunity of cannibal cells was induced by bacillunoic acids. A two-component system, the OmpS-OmpR signal-transduction pathway, controls the expression of the ABC transporter BnaAB for self-immunity. Specifically, bacillunoic acids activate the autophosphorylation of OmpS, a transmembrane histidine kinase, which then transfers a phosphoryl group to its response regulator OmpR. The phosphorylation of OmpR activates the transcription of the transporter gene bnaAB by binding its promoter. Thus, bacillunoic acids are pumped out of cells by the ABC transporter BnaAB. Moreover, we discovered that strain SQR9 could use the bacillunoic acids-mediated cannibalism to optimize its community to produce more bacillunoic acids for bacterial competition. This study revealed that bacillunoic acids play a previously undiscovered dual role in both cannibalism during biofilm formation and interspecies competition, which has an important biological significance.

microbiology↗

bioRxiv2021

Integrative Analysis of Spatial Transcriptome with Single-cell Transcriptome and Single-cell Epigenome in Mouse Lungs after Immunization

Immunological memory is key to productive adaptive immunity. An unbiased, high throughput gene expression profiling of tissue-resident memory T cells at their precise anatomical locations within the lung is fundamental to understanding lung immunity, but such spatial information has yet to be characterized. In this study, using a well-established Klebsiella pneumoniae infection model, we performed an integrative analysis of spatial transcriptome with single-cell RNA-seq and single-cell ATAC-seq on lung cells from mice after immunization using the 10x Genomics Chromium and Visium platform. We employed several deconvolution algorithms and established an optimized deconvolution pipeline to accurately decipher specific cell-type composition by anatomic location. We identified and located 12 major cell types by scRNA-seq and spatial transcriptomic analysis. Integrating scATAC-seq data from the same cells processed in parallel with scRNA-seq, we found epigenomic profiles provide more robust cell type identification, especially for lineage-specific T helper cells. When combining all three data modalities, we observed a dynamic change in the location of T helper cells as well as their corresponding chemokines for chemotaxis. Furthermore, cell-cell communication analysis of spatial transcriptome provided evidence of lineage-specific T helper cells receiving designated cytokine signaling. In summary, our first-in-class study demonstrated the power of multi-omics analysis to uncover intrinsic spatial- and cell-type-dependent molecular mechanisms of lung immunity. Our data provides a rich research resource of single cell multi-omics data as a reference for understanding spatial dynamics of lung immunization.

bioinformatics↗

bioRxiv2021

Adipocyte-specific modulation of KLF14 expression in mice leads to sex-dependent impacts in adiposity and lipid metabolism

Genome-wide association studies identified single nucleotide polymorphisms on chromosome 7 upstream of KLF14 to be associated with metabolic syndrome traits and increased risk for Type 2 Diabetes (T2D). The associations were more significant in women than in men. The risk allele carriers expressed lower levels of the transcription factor KLF14 in adipose tissues than non-risk allele carriers. To investigate how adipocyte KLF14 regulates metabolic traits in a sex-dependent manner, we characterized high-fat diet fed male and female mice with adipocyte-specific Klf14 deletion or overexpression. Klf14 deletion resulted in increased fat mass in female mice and decreased fat mass in male mice. Female Klf14-deficient mice had overall smaller adipocytes in subcutaneous fat depots but larger adipocytes in parametrial depots, indicating a shift in lipid storage from subcutaneous to visceral fat depots. They had reduced metabolic rates and increased respiratory exchange ratios consistent with increased utilization of carbohydrates as an energy source. Fasting and isoproterenol-induced adipocyte lipolysis was defective in female Klf14-deficient mice and concomitantly adipocyte triglycerides lipase mRNA levels were downregulated. Female Klf14-deficient mice cleared blood triglyceride and NEFA less efficiently than wild type. Finally, adipocyte-specific overexpression of Klf14 resulted in lower total body fat in female but not male mice. Taken together, consistent with human studies, adipocyte KLF14 deficiency in female but not in male mice causes increased adiposity and redistribution of lipid storage from subcutaneous to visceral adipose tissues. Increasing KLF14 abundance in adipocytes of females with obesity and T2D may provide a novel treatment option to alleviate metabolic abnormalities.

physiology↗

bioRxiv2021

Structural and molecular rationale for the diversification of resistance mediated by the Antibiotic_NAT family

The environmental microbiome harbors a vast repertoire of antibiotic resistance genes (ARGs) which can serve as evolutionary predecessors for ARGs found in pathogenic bacteria, or can be directly mobilized to pathogens in the presence of selection pressures. Thus, ARGs from benign environmental bacteria are an important resource for understanding clinically relevant resistance. Here, we conduct a comprehensive functional analysis of the Antibiotic_NAT family of aminoglycoside acetyltransferases. We determined a pan-family antibiogram of 21 Antibiotic_NAT enzymes, including 8 derived from clinical isolates and 13 from environmental metagenomic samples. We find that environment-derived representatives confer high-level, broad-spectrum resistance, including against the atypical aminoglycoside apramycin, and that a metagenome-derived gene likely is ancestral to an AAC(3) gene found in clinical isolates. Through crystallographic analysis, we rationalize the molecular basis for diversification of substrate specificity across the family. This work provides critical data on the molecular mechanism underpinning resistance to established and emergent aminoglycoside antibiotics and broadens our understanding of ARGs in the environment.

microbiology↗

bioRxiv2021

A MYB transcription factor, PlMYB308, plays an essential role in flower senescence of herbaceous peony

Herbaceous peony is an important cut-flower plant cultivated across the world, but its short vase life substantially restricts the economic value of this crop. It is well established that endogenous hormones regulate the senescing process, but the molecular mechanism of them in flower senescence is still unclear. Here, we isolated a MYB transcription factor gene PlMYB308 from herbaceous peony flowers. Transcript abundance of PlMYB308 was strongly up-regulated in senescing petals. Silencing of PlMYB308 resulted in delayed peony flower senescence, and dramatically increased gibberellin (GA) but reduced ethylene and abscisic acid (ABA) levels in petals. Ectopic overexpression of PlMYB308 in tobacco accelerated flower senescence, and reduced GA but increased ethylene and ABA accumulation. Correspondingly, biosynthetic genes of ethylene, ABA, and GA showed variable expression levels in petals after silencing or overexpression of PlMYB308. A dual-luciferase assay showed that PlMYB308 specifically bound to the PlACO1 promoter. High expression levels of PlMYB308 were accompanied by low petal anthocyanin accumulation in senescing petals. A further bimolecular fluorescence complementation assay revealed an interaction between PlMYB308 and PlbHLH33, which was supposed to inhibit the anthocyanin biosynthesis. Taken together, our results suggest that the PlMYB308-PlACO1 and PlMYB308-PlbHLH33 regulatory checkpoints perhaps positively and negatively operate the production of ethylene and anthocyanin, respectively, and thus contribute to the senescence with impaired pigmentation in herbaceous peony flowers.

biophysics↗

bioRxiv2021

Nanomolar, noncovalent antagonism of hedgehog cholesterolysis: exception to the irreversibility rule for protein autoprocessing inhibition.

Hedgehog (Hh) signaling ligands undergo carboxy terminal sterylation through specialized autoprocessing, called cholesterolysis. Sterylation is brought about intramolecularly in a single turn-over by an enzymatic domain, called HhC. HhC is found in precursor Hh proteins only. Through cholesterolysis, HhC is cleaved from the precursor. Attempts to identify molecules that inhibit intramolecular cleavage/sterylation activity of HhC have resulted in antagonists that bind HhC irreversibly through covalent mechanisms, as is commonplace for protein autoprocessing inhibitors. Here we report an exception to the "irreversibility rule" for protein autoprocessing inhibition. Using a FRET-based activity assay for HhC, we screened a focused library of sterol-like analogs for HhC cholesterolysis inhibitors. We identified and validated four structurally related noncovalent inhibitors, which were then used for SAR studies. The most effective derivative, tBT-HBT, binds HhC reversibly with an IC50 of 300 nM. An allosteric binding site for tBT-HBT, encompassing interactions from the two subdomains of HhC, is suggested by kinetic analysis, mutagenesis studies, and photoaffinity labeling. A striking resemblance is found between the inhibitors described here and a family of noncovalent, allosteric activators of HhC, which we described previously. The inhibitor/activator duality appears to be mediated by the same allosteric site, which displays sensitivity to subtle differences in the structure of a heterocycle substituent on the effector molecule.

biochemistry↗

bioRxiv2021

Bone-Specific Enhancement of Antibody Therapy for Breast Cancer Metastasis to Bone

Therapeutic antibodies have gone a long way toward realizing their clinical potential and have become very useful for treating a variety of pathologies. Despite the rapid evolution of therapeutic antibodies, their clinical efficacy in treatment of bone tumors has been hampered by the inadequate pharmacokinetics and poor bone tissue accessibility of these large macromolecules. Here, we show that engineering therapeutic antibodies to include bone-homing peptide sequences dramatically enhances their concentration in the bone metastatic niche, resulting in significantly reduced survival and progression of breast cancer bone metastases. To enhance the bone tumor-targeting ability of engineered antibodies, we introduced varying numbers of a bone-homing peptide into permissive internal sites of the anti-HER2 antibody trastuzumab. Compared to the unmodified antibody, the engineered bone-targeting antibodies have similar pharmacokinetics and in vitro cytotoxic activity against HER2-positive cancer cells, but exhibit improved bone tumor distribution in vivo. Accordingly, in xenograft models of breast cancer metastasis to bone sites, engineered antibodies with enhanced bone specificity exhibit increased inhibition of both initial bone metastases and secondary multi-organ metastases from bone lesions. Furthermore, this engineering strategy is also applied to prepare bone-targeting antibody-drug conjugates with enhanced therapeutic efficacy. These results demonstrate that adding bone-specific targeting to antibody therapy results in robust delivery of therapeutic antibodies to the bone tumor niche. This provides a powerful strategy for overcoming inadequate treatment of bone cancer and the development of potentially acquired resistance to therapy.

bioengineering↗

bioRxiv2021

Biosynthetic gene cluster profiling predicts the positive association between antagonism and phylogeny in Bacillus

Understanding the driving forces and intrinsic mechanisms of microbial competition is a fundamental question in microbial ecology. Despite the well-established negative correlation between exploitation competition and phylogenetic distance, the process of interference competition that is exemplified by antagonism remains controversial. Here, we studied the genus Bacillus, a commonly recognized producer of multifarious antibiotics, to explore the role of phylogenetic patterns of biosynthetic gene clusters (BGCs) in mediating the relationship between antagonism and phylogeny. Comparative genomic analysis revealed a positive association between BGC distance and phylogenetic distance. Antagonistic tests demonstrated that the inhibition phenotype positively correlated with both phylogenetic and predicted BGC distance, especially for antagonistic strains possessing abundant BGCs. Mutant-based verification showed that the antagonism was dependent on the BGCs that specifically harbored by the antagonistic strain. These findings highlight that BGC-phylogeny coherence regulates the positive correlation between congeneric antagonism and phylogenetic distance, which deepens our understanding of the driving force and intrinsic mechanism of microbial interactions.

ecology↗

bioRxiv2021

Optical Control of Invertebrate nAChR and Behaviors with Dithienylethene-Imidacloprid

Photopharmacology has changed established methods of studying receptor functions, allowing for increasing spatiotemporal resolution. However, no photopharmacological tools are available for the invertebrate nicotinic acetylcholine receptor (nAChR). Here, we report a photochromic ligand, dithienylethene-imidacloprid (DitIMI), targeting invertebrate nAChR. We demonstrated that DitIMI has low spontaneous in vivo and in vitro activity but can be photoisomerized to a highly active closed-form. This photoisomerization can further be translated to photomodulation of neuron membrane potential and behavioral responses of living mosquito larvae and American cockroaches. Furthermore, we discovered that DitIMI is a specific reporter for fluorescence polarization based high-throughput screening of nAChR ligands.

molecular biology↗

bioRxiv2021

Single-shot rAAV5-based Vaccine Provides Long-term Protective Immunity against SARS-CoV-2 and Its Variants

The COVID-19 pandemic and the SARS-CoV-2 with its variants have posed unprecedented challenges worldwide. Existing vaccines have limited effectiveness against the SARS-CoV-2 variants. Therefore, novel vaccines to match current mutated viral lineages with long-term protective immunity are urgently in demand. In the current study, we for the first time designed a recombinant Adeno-Associated Virus 5 (rAAV5)-based vaccine named as rAAV-COVID-19 vaccine (Covacinplus) by using RBD-plus of spike protein with both the single-stranded and the self-complementary AAV5 delivering vectors (ssAAV5 and scAAAV5), which provides excellent protection from SARS-CoV-2 infection. A single dose vaccination induced the strong immune response against SARS-CoV-2. The induced neutralizing antibodies (NAs) titers were maintained at a high peak level of over 1:1024 even after more than one year of injection and accompanied with functional T-cells responses in mice. Importantly, both ssAAV- and scAAV-based RBD-plus vaccines exhibited high levels of serum NAs against current circulating variants including variants Alpha, Beta, Gamma and Delta. SARS-CoV-2 virus challenge test showed that ssAAV5-RBD-plus vaccine protected both young and old age mice from SARS-CoV-2 infection in the upper and the lower respiratory tracts. Moreover, whole genome sequencing demonstrated that AAV vector DNA sequences were not found in the genome of the vaccinated mice after one year vaccination, demonstrating excellent safety of the vaccine. Taken together, this study suggests that rAAV5-based vaccine is powerful against SARS-CoV-2 and its variants with long-term protective immunity and excellent safety, which has great potential for development into prophylactic vaccination in human to end this global pandemic.

immunology↗