Biology subjects

Zhang, G.

Publications and source records attributed to Zhang, G..

At least 361 records · Page 20Linked to original sources

bioRxiv2021

Individual structural MRI abnormality indexes are associated with molecular,histological and cognitive indicators for frontal glioma patients

Although every glioma patient varies in tumor size, location, histological grade and molecular biomarkers, structural abnormalities are commonly conducted in a group-level, leading to the miss of individual structural atrophy. In this study, we introduced an individual-level structural abnormality detection method for glioma patients and proposed several novel abnormality indexes to depict the individual atrophy pattern. Forty-five glioma patients in frontal lobe and fifty-two age-matched healthy controls participated in the study. All patients underwent neurocognitive test and molecular examinations, including 1p/19q co-deletion, isocitrate dehydrogenase (IDH) mutation, telomerase reverse transcriptase (TERT) promoter mutation and O6-methylguanine-DNA methyltransferase (MGMT) promotor methylation. Individual structural abnormality maps for every glioma patient were calculated from the preoperative T1 images, and the individual abnormality index were further computed and explored the associations with clinical indicators. The results manifested that: 1. Every glioma patient show unique atrophy pattern; 2. Glioma patients also share consistent atrophy regions; 3. The atrophy pattern is influenced by some molecular biomarkers. Our study provides an effective way to access the individual structural abnormalities in glioma patients, and displays great potentials in individualized precision medicine for glioma patients.

neuroscience↗

bioRxiv2021

MMpred: a distance-assisted multimodal conformation sampling for de novo protein structure prediction

MotivationThe mathematically optimal solution in computational protein folding simulations does not always correspond to the native structure, due to the imperfection of the energy force fields. There is therefore a need to search for more diverse suboptimal solutions in order to identify the states close to the native. We propose a novel multimodal optimization protocol to improve the conformation sampling efficiency and modeling accuracy of de novo protein structure folding simulations. ResultsA distance-assisted multimodal optimization sampling algorithm, MMpred, is proposed for de novo protein structure prediction. The protocol consists of three stages: The first is a modal exploration stage, in which a structural similarity evaluation model DMscore is designed to control the diversity of conformations, generating a population of diverse structures in different low-energy basins. The second is a modal maintaining stage, where an adaptive clustering algorithm MNDcluster is proposed to divide the populations and merge the modal by adjusting the annealing temperature to locate the promising basins. In the last stage of modal exploitation, a greedy search strategy is used to accelerate the convergence of the modal. Distance constraint information is used to construct the conformation scoring model to guide sampling. MMpred is tested on a large set of 320 non-redundant proteins, where MMpred obtains models with TM-score[≥]0.5 on 268 cases, which is 20.3% higher than that of Rosetta guided with the same set of distance constraints. The results showed that MMpred can help significantly improve the model accuracy of protein assembly simulations through the sampling of multiple promising energy basins with enhanced structural diversity. AvailabilityThe source code and executable versions are freely available at https://github.com/iobio-zjut/MMpred. Contactzgj@zjut.edu.cn or zhng@umich.edu or sujz@wmu.edu.cn

bioinformatics↗

bioRxiv2021

Silencing of lncRNA NEAT1 inhibits esophageal squamous cell carcinoma proliferation, migration, and invasion via regulation of the miR-1299/MMP2 axis

Esophageal squamous cell carcinoma (ESCC) is the most prevalent form of esophageal cancer worldwide. Considerable evidence has verified that abnormal expression of lncRNAs can effectively influence the progression of various malignant tumors. However, the regulatory mechanisms of lncRNAs underlying ESCC development and progression remain poorly defined. Here, we investigated the role of lncRNA nuclear-enriched abundant transcript 1 (NEAT1) in ESCC via regulating microRNA 1299 (miR-1299) and matrix metalloproteinase 2 (MMP2). A total of 32 ESCC tissue samples were obtained from the First Affiliated Hospital of Zhengzhou University. The mRNA levels of lncRNA NEAT1, miR-1299, and MMP2 mRNA were measured via quantitative real-time PCR. Interactions among miR-1299, lncRNA NEAT1, and MMP2 mRNA in EC9706 cells were confirmed by dual-luciferase reporter assays and RNA immunoprecipitation (RIP) assays. The proliferation and migration/invasion of ESCC cells were verified by CCK-8 and transwell assays, respectively. lncRNA NEAT1 was up-regulated in ESCC tissues and cells. lncRNA NEAT1 silencing inhibited migration, invasion, and proliferation of ESCC cells. Furthermore, lncRNA NEAT1 sponged and negatively regulated miR-1299, thus giving rise to increased expression of MMP2. Moreover, miR-1299 inhibitors and MMP2 rescued the invasion of ESCC cells following silencing of lncRNA NEAT1. lncRNA NEAT1 was overexpressed in ESCC tissues and cells. Silencing of lncRNA NEAT1 inhibited ESCC proliferation, migration, and invasion via reducing competitive binding of lncRNA NEAT1 with miR-1299 and enhancing miR-1299-targeted suppression of MMP2. Taken together, our findings suggest that lncRNA NEAT1 is a potential target for ESCC therapy and rehabilitation.

cancer biology↗

bioRxiv2021

Genome recombination-mediated tRNA up-regulation conducts general antibiotic resistance of bacteria at early stage

Bacterial antibiotic resistance sets a great challenge to human health. It seems that the bacteria can spontaneously evolve resistance against any antibiotic within short time without the horizontal transfer of heterologous genes and before accumulating drug-resistant mutations. We have shown that the tRNA-mediated translational regulation counteracts the reactive oxygen species in bacteria. In this study, we demonstrated that isolated and subcultured Escherichia coli elevated its tRNAs under antibiotic stress to rapidly provide antibiotic resistance, especially at the early stage, before upregulating the efflux pump and evolving resistance mutations. The DNA recombination system repaired the antibiotic-induced DNA breakage in the genome, causing numerous structural variations. These structural variations are overrepresented near the tRNA genes, which indicated the cause of tRNA up-regulation. The strains knocking out the recombination system could not up-regulate tRNAs, and coincidently, they could hardly evolve antibiotic resistance in multiple antibiotics, respectively. With these results, we proposed a multi-stage model of bacterial antibiotic resistance in an isolated scenario: the early stage (recombination - tRNA up-regulation - translational regulation); the medium stage (up-regulation of efflux pump); the late stage (resistance mutations). These results also indicated that the bacterial DNA recombination system and tRNA could be targeted to retard the bacterial spontaneous drug resistance.

microbiology↗

bioRxiv2021

Deficiency of gluconeogenic enzyme PCK1 promotes non-alcoholic steatohepatitis progression by activation of PI3K/AKT/PDGF axis

Nonalcoholic steatohepatitis (NASH) is a chronic liver disease characterized by hepatic lipid accumulation, inflammation, and progressive fibrosis. We demonstrated that phosphoenolpyruvate carboxykinase 1 (PCK1) plays a central role in NASH progression. Mice with liver Pck1 deficiency fed a normal diet displayed hepatic lipid disorder and liver injury, whereas fibrosis and inflammation were aggravated in mice fed a NASH diet. Forced expression of PCK1 by adeno-associated virus in the liver ameliorated NASH in mice. PCK1 deficiency stimulated lipogenic gene expression and lipid synthesis. Moreover, loss of hepatic PCK1 activated the RhoA/PI3K/AKT pathway by increasing intracellular GTP levels, increasing secretion of platelet-derived growth factor-AA (PDGF-AA), and promoting hepatic stellate cell activation. Treatment with RhoA and AKT inhibitors or gene silencing of RhoA or AKT1 alleviated NASH progression in vivo. Hepatic PCK1 deficiency may be important in hepatic steatosis and fibrosis development through paracrine secretion of PDGF-AA, highlighting a therapeutic strategy for NASH.

molecular biology↗

bioRxiv2021

Elevated concentration and nitrogen addition affects responses of foliar phosphorus fractions in invasive species to increased phosphorus supply

No studies have explored how the invasive species of Mikania micranatha and Chromolaena odoratan adjust leaf phosphorus (P) among inorganic P (Pi) and organic P fractions to adapt the low soil P availability, especially under elevated CO2 concentrations ([CO2]) and nitrogen (N) deposition. Here, we address this by measuring foliar total N and P concentrations as well as functional P fractions (i.e. Pi, metabolic P, lipid P, nucleic acids P, and residual P) of both invasive species and a native species (Paederia. scandens) growing under different P supplies, N, and N+P addition under both ambient and elevated [CO2]. Phosphorus addition greatly increased plant biomass and foliar P concentrations but did not significantly affect foliar N concentration and leaf mass per unit leaf area (LMA). In response to P addition, the concentration of metabolic P increased the most, followed by that of nucleic acid P, Pi, and lipid P, in all species by an average of 754%, 82%, 53%, and 38%, respectively. However, elevated [CO2] and N addition weakened this positive effect on concentrations of foliar P fractions in the invasive species. Our results indicate that elevated [CO2] and N addition allowed the invasive species to acclimate to a low soil P availability, supporting their successful invasion, through greatly reducing P allocation to non-metabolic foliar P fractions (phospholipids and nucleic acid P) to meet their demand for metabolic P and Pi for photosynthesis, rather than altering LMA.

plant biology↗

bioRxiv2020

A Sequential Niche Multimodal Conformation Sampling Algorithm for Protein Structure Prediction

MotivationMassive local minima on the protein energy surface often causes traditional conformation sampling algorithms to be easily trapped in local basin regions, because they are difficult to stride over high-energy barriers. Also, the lowest energy conformation may not correspond to the native structure due to the inaccuracy of energy models. This study investigates whether these two problems can be alleviated by a sequential niche technique without loss of accuracy. ResultsA sequential niche multimodal conformation sampling algorithm for protein structure prediction (SNfold) is proposed in this study. In SNfold, a derating function is designed based on the knowledge learned from the previous sampling and used to construct a series of sampling-guided energy functions. These functions then help the sampling algorithm stride over high-energy barriers and avoid the re-sampling of the explored regions. In inaccurate protein energy models, the high- energy conformation that may correspond to the native structure can be sampled with successively updated sampling-guided energy functions. The proposed SNfold is tested on 300 benchmark proteins and 24 CASP13 FM targets. Results show that SNfold is comparable with Rosetta restrained by distance (Rosetta-dist) and C-QUARK. SNfold correctly folds (TM-score [≥] 0.5) 231 out of 300 proteins. In particular, compared with Rosetta-dist protocol, SNfold achieves higher average TM- score and improves the sampling efficiency by more than 100 times. On the 24 CASP13 FM targets, SNfold is also comparable with four state-of-the-art methods in the CASP13 server group. As a plugin conformation sampling algorithm, SNfold can be extended to other protein structure prediction methods. AvailabilityThe source code and executable versions are freely available at https://github.com/iobio-zjut/SNfold. Contactzgj@zjut.edu.cn

bioinformatics↗

bioRxiv2020

Functional Characterization of a Lassa Virus Fusion Inhibitors Adaptive Mutant

Lassa virus (LASV) glycoprotein complex (GPC) contains retained stable-signal peptide (SSP), GP1, and GP2. SSP interacts with GP2 and provides an interface targeted by numerous fusion inhibitors. Serially passaging of LASV with inhibitors allowed some adaptive mutants to be obtained of which most had mutations located in the transmembrane (TM) domain of GP2. In the current study, we focused on the F446L mutant, which is reported to confer resistance to ST-series inhibitors. We found that F446L conferred cross-resistance to structurally distinct inhibitors. Furthermore, F446L increased the fusion activities of LASV and Mopeia virus GPC, elevating the pH threshold for fusion of LASV and promoting fusion of MOPV at neutral pH. F446L exerted little effect on the pseudotype viral growth profile or thermostability. By introducing other residues to the conserved F446 locus, it was found that this site was less compatible with a similar tyrosine residue and was intolerable to charged residues. These results help characterize the fusion inhibitor target located in the TM domain of GP2, which should be useful for drug and vaccine design. IMPORTANCEThe LASV SSP-GP2 interface provides an Achilles heel that is targeted by numerous inhibitors. However, the emergence of resistant viruses is a major concern for direct antiviral drugs. In this study, we investigated the F446L mutant located in the GPC TM domain to determine the relationship between drug resistance, membrane fusion activity, viral growth kinetics, and thermostability. These results will be helpful in monitoring drug-resistant variants, as well as the advancement of drug and vaccine design.

microbiology↗

bioRxiv2020

From egg to adult: a developmental table of the ant Monomorium pharaonis

Ants are one of the most ecologically and evolutionarily successful groups of animals and exhibit a remarkable degree of phenotypic diversity. This success is largely attributed to the fact that all ants are eusocial and live in colonies with a reproductive division of labor between morphologically distinct queen and worker castes. Yet, despite over a century of studies on caste determination and evolution in ants, we lack a complete ontogenetic series from egg to adult for any ant species. We therefore present a developmental table for the Pharaoh ant Monomorium pharaonis, a species whose colonies simultaneously produce both reproductive queens and completely sterile workers. In total, M. pharaonis embryonic, larval, and pupal development lasts 45 days. During embryogenesis, the majority of developmental events are conserved between M. pharaonis and the fruit fly Drosophila melanogaster. However, we discovered two types of same-stage embryos prior to gastrulation: (1) embryos with internalized germ cells; and (2) embryos with germ cells outside of the blastoderm at the posterior pole. Moreover, we found two-types of embryos following germ band extension: (1) fertile embryos with primordial germ cells; and (2) sterile embryos with no germ cells. Together, our data shows that the queen (fertile) and worker (sterile) phenotypes are already determined and differentiated by early embryogenesis. During larval development, previous studies and our data find 3 larval instars reproductives and workers. However, there is considerable variation within each caste-specific instar, making it difficult to lineate instar boundaries. Here, we propose that developmental and anatomical markers can segregate larvae into gyne (unmatted queen), male and worker castes, including during the 1st larval instar. Overall, we hope that the ontogenetic series we present here will serve as a blueprint for the generation of future ant developmental tables.

developmental biology↗

bioRxiv2020

Oxidized LDL but not angiotensin II induces the interaction between LOX-1 and AT1 receptors

Oxidized low-density lipoprotein (Ox-LDL) can induce cardiac hypertrophy, but the mechanism is still unclear. Here we elucidate the role of angiotensin II (AngII) receptor (AT1-R) in Ox-LDL-induced cardiomycyte hypertrophy. Inhibition of Ox-LDL receptor LOX-1 and AT1-R rather than AngII abolished Ox-LDL-induced hypertrophic responses. Similar results were obtained from the heart of mice lacking endogenous Ang II and their cardiomyocytes. Ox-LDL but not AngII induced binding of LOX-1 to AT1-R, and the inhibition of LOX-1 or AT1-R rather than AngII abolished the association of these two receptors. Ox-LDL-induced ERKs phosphorylation in LOX-1 and AT1-R-overexpression cells and the binding of both receptors were suppressed by the mutants of LOX-1 (Lys266Ala/Lys267Ala) or AT1-R (Glu257Ala), however, the AT1-R mutant lacking Gq protein-coupling ability only abolished the ERKs phosphorylation. The phosphorylation of ERKs induced by Ox-LDL in LOX-1 and AT1-R-overexpression cells was abrogated by Gq protein inhibitor but not by Jak2, Rac1 and RhoA inhibitors. Therefore, the direct interaction between LOX-1 and AT1-R and the downstream Gq protein activation are important mechanisms for Ox-LDL-but not AngII-induced cardiomyocyte hypertrophy.

cell biology↗

bioRxiv2020

An interactive viral genome evolution network analysis system enabling rapid large-scale molecular tracing of SARS-CoV-2

Comprehensive analyses of viral genomes can provide a global picture on SARS-CoV-2 transmission and help to predict the oncoming trends of pandemic. This molecular tracing is mainly conducted through extensive phylogenetic network analyses. However, the rapid accumulation of SARS-CoV-2 genomes presents an unprecedented data size and complexity that has exceeded the capacity of existing methods in constructing evolution network through virus genotyping. Here we report a Viral genome Evolution Network Analysis System (VENAS), which uses Hamming distances adjusted by the minor allele frequency to construct viral genome evolution network. The resulting network was topologically clustered and divided using community detection algorithm, and potential evolution paths were further inferred with a network disassortativity trimming algorithm. We also employed parallel computing technology to achieve rapid processing and interactive visualization of >10,000 viral genomes, enabling accurate detection and subtyping of the viral mutations through different stages of Covid-19 pandemic. In particular, several core viral mutations can be independently identified and linked to early transmission events in Covid-19 pandemic. As a general platform for comprehensive viral genome analysis, VENAS serves as a useful computational tool in the current and future pandemics.

evolutionary biology↗

bioRxiv2020

Reinforcing neuron extraction and spike inference in calcium imaging using deep self-supervised learning

Calcium imaging is inherently susceptible to detection noise especially when imaging with high frame rate or under low excitation dosage. We developed DeepCAD, a self-supervised learning method for spatiotemporal enhancement of calcium imaging without requiring any high signal-to-noise ratio (SNR) observations. Using this method, detection noise can be effectively suppressed and the imaging SNR can be improved more than tenfold, which massively improves the accuracy of neuron extraction and spike inference and facilitate the functional analysis of neural circuits.

neuroscience↗

bioRxiv2020

A new duck genome reveals conserved and convergently evolved chromosome architectures of birds and mammals

BackgroundDucks have a typical avian karyotype that consists of macro- and microchromosomes, but a pair of much less differentiated ZW sex chromosomes compared to chicken. To elucidate the evolution of chromosome architectures between duck and chicken, and between birds and mammals, we produced a nearly complete chromosomal assembly of a female Pekin duck by combining long-read sequencing and multiplatform scaffolding techniques. ResultsThe major improvement of genome assembly and annotation quality resulted from successful resolution of lineage-specific propagated repeats that fragmented the previous Illumina-based assembly. We found that the duck topologically associated domains (TAD) are demarcated by putative binding sites of the insulator protein CTCF, housekeeping genes, or transitions of active/inactive chromatin compartments, indicating the conserved mechanisms of spatial chromosome folding with mammals. There are extensive overlaps of TAD boundaries between duck and chicken, and also between the TAD boundaries and chromosome inversion breakpoints. This suggests strong natural selection on maintaining regulatory domain integrity, or vulnerability of TAD boundaries to DNA double-strand breaks. The duck W chromosome retains 2.5-fold more genes relative to chicken. Similar to the independently evolved human Y chromosome, the duck W evolved massive dispersed palindromic structures, and a pattern of sequence divergence with the Z chromosome that reflects stepwise suppression of homologous recombination. ConclusionsOur results provide novel insights into the conserved and convergently evolved chromosome features of birds and mammals, and also importantly add to the genomic resources for poultry studies.

genomics↗

bioRxiv2020

TCR affinity controls the dynamics but not the functional specification of the Th1 response to mycobacteria

The quality of T cell responses depends on the lymphocytes ability to undergo clonal expansion, acquire effector functions and traffic to the site of infection. Although TCR signal strength is thought to dominantly shape the T cell response, by using TCR transgenic CD4+ T cells with different pMHC binding affinity, we reveal that TCR affinity does not control Th1 effector function acquisition nor the functional output of individual effectors following mycobacterial infection. Rather, TCR affinity calibrates the rate of cell division to synchronize the distinct processes of T cell proliferation, differentiation and trafficking. By timing cell division-dependent IL-12R expression, TCR affinity controls when T cells become receptive to Th1-imprinting IL-12 signals, determining the emergence and magnitude of the Th1 effector pool. These findings reveal a distinct yet cooperative role for IL-12 and TCR signalling in Th1 differentiation and suggests that the temporal activation of clones with different TCR affinity is a major strategy to coordinate immune surveillance against persistent pathogens.

immunology↗

bioRxiv2020

Rice Calcium/Calmodulin-Dependent Protein Kinase Directly Phosphorylates a Mitogen-Activated Protein Kinase Kinase to Regulate Abscisic Acid Responses

Ca2+/calmodulin (CaM)-dependent protein kinase (CCaMK) is an important positive regulator of abscisic acid (ABA) and abiotic stress signaling in plants and is believed to act upstream of mitogen-activated protein kinase (MAPK) in ABA signaling. However, it is unclear how CCaMK activates MAPK in ABA signaling. Here, we show that OsDMI3, a rice (Oryza sativa) CCaMK, directly interacts with and phosphorylates OsMKK1, a MAPK kinase (MKK) in rice, in vitro and in vivo. OsDMI3 was found to directly phosphorylate Thr-25 in the N-terminus of OsMKK1, and this Thr-25 phosphorylation is OsDMI3-specific in ABA signaling. The activation of OsMKK1 and its downstream kinase OsMPK1 is dependent on Thr-25 phosphorylation of OsMKK1 in ABA signaling. Moreover, ABA treatment also induces the phosphorylation in the activation loop of OsMKK1, and the two phosphorylations in the N-terminus and in the activation loop are independent. Further analyses revealed that OsDMI3-mediated phosphorylation of OsMKK1 positively regulates ABA responses in seed germination, root growth, and tolerance to both water stress and oxidative stress. Our results indicate that OsMKK1 is a direct target of OsDMI3, and OsDMI3-mediated phosphorylation of OsMKK1 plays an important role in the activation of MAPK cascade and ABA signaling. One-sentence summaryOsMKK1 is a direct target of OsDMI3, and OsDMI3-mediated phosphorylation of OsMKK1 plays an important role in the activation of MAPK cascade and ABA signaling. The author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantcell.org) is: Mingyi Jiang (myjiang@njau.edu.cn)

plant biology↗

bioRxiv2020

Progressive and accurate assembly of multi-domain protein structures from cryo-EM density maps

Progress in cryo-electron microscopy (cryo-EM) has provided the potential for large-size protein structure determination. However, the solution rate for multi-domain proteins remains low due to the difficulty in modeling inter-domain orientations. We developed DEMO-EM, an automatic method to assemble multi-domain structures from cryo-EM maps through a progressive structural refinement procedure combining rigid-body domain fitting and flexible assembly simulations with deep neural network inter-domain distance profiles. The method was tested on a large-scale benchmark set of proteins containing up to twelve continuous and discontinuous domains with medium-to-low-resolution density maps, where DEMO-EM produced models with correct inter-domain orientations (TM-score >0.5) for 98% of cases and significantly outperformed the state-of-the-art methods. DEMO-EM was applied to SARS-Cov-2 coronavirus genome and generated models with average TM-score/RMSD of 0.97/1.4[A] to the deposited structures. These results demonstrated an efficient pipeline that enables automated and reliable large-scale multi-domain protein structure modeling with atomic-level accuracy from cryo-EM maps.

bioinformatics↗

bioRxiv2020

Coupling of H3K27me3 recognition with transcriptional repression through the BAH-PHD-CPL2 complex in Arabidopsis

Histone 3 Lys 27 trimethylation (H3K27me3)-mediated epigenetic silencing plays a critical role in multiple biological processes. However, the H3K27me3 recognition and transcriptional repression mechanisms are only partially understood. Here, we report a new mechanism for H3K27me3 recognition and transcriptional repression. Our structural and biochemical data showed that the BAH domain protein AIPP3 and the PHD proteins AIPP2 and PAIPP2 cooperate to read H3K27me3 and unmodified H3K4 histone marks, respectively, in Arabidopsis. The BAH-PHD bivalent histone reader complex silences a substantial subset of H3K27me3-enriched loci, including a number of development and stress response-related genes such as the RNA silencing effector gene ARGONAUTE 5 (AGO5) and We found that the BAH-PHD module associates with CPL2, a plant-specific Pol II carboxyl terminal domain (CTD) phosphatase, to form the BAH-PHD-CPL2 complex (BPC) for transcriptional repression. The BPC complex represses transcription through CPL2-mediated CTD dephosphorylation, thereby causing inhibition of Pol II release from the transcriptional start site. Our work reveals a mechanism coupling H3K27me3 recognition with transcriptional repression through the alteration of Pol II phosphorylation states, thereby contributing to our understanding of the mechanism of H3K27me3-dependent silencing.

plant biology↗

bioRxiv2020

De Novo Discovery of High Affinity Peptide Binders for the SARS-CoV-2 Spike Protein

The {beta}-coronavirus SARS-CoV-2 has caused a global pandemic. Affinity reagents targeting the SARS-CoV-2 spike protein, the most exposed surface structure of the virus, are of interest for the development of therapeutics and diagnostics. We used affinity selection-mass spectrometry for the rapid discovery of synthetic high affinity peptide binders for the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. From library screening with 800 million synthetic peptides, we identified three sequences with nanomolar affinities (dissociation constants Kd = 80 to 970 nM) for RBD and selectivity over human serum proteins. Picomolar RBD concentrations in biological matrix could be detected using the biotinylated lead peptide in ELISA format. These peptides might associate with the SARS-CoV-2-spike-RBD at a site unrelated to ACE2 binding, making them potential orthogonal reagents for sandwich immunoassays. We envision our discovery as a robust starting point for the development of SARS-CoV-2 diagnostics or conjugates for virus directed delivery of therapeutics. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=100 SRC="FIGDIR/small/317131v1_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@803e9borg.highwire.dtl.DTLVardef@18e5d74org.highwire.dtl.DTLVardef@1998310org.highwire.dtl.DTLVardef@16ba5cc_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗