Journal: International Journal of Molecular Sciences

Article Title: tRNA Modifications: A Tale of Two Viruses—SARS-CoV-2 and ZIKV

doi: 10.3390/ijms26157479

Figure Lengend Snippet: Elongator complex loss reduces SARS-CoV-2 and ZIKV infection. ( A ) Schematic representation of U34 tRNA modification pathway in FD (ELP1-deficient) cells. The Western blot shows ACE2 receptor and actin levels in cells transduced by ACE2-expressing lentivector (VLP ACE2 ). ( B ) Quantification of U34 modification levels (ncm 5 U, mcm 5 U, and mcm 5 s 2 U) in wild-type ( wt ) versus FD cells determined by mass spectrometry on tRNA-enriched RNA fractionations. ( C ) SARS-CoV-2 infection levels measured by RT-qPCR in wt and FD cells at different multiplicities of infection (MOI) 24 h post-infection. ( D ) ZIKV infection levels measured by RT-qPCR in wt and FD cells at different MOIs 48 h post-infection.

Article Snippet: Seventy-two hours after transduction, accurate ACE2 expression was controlled by Western blots using anti-ACE2 antibody (Human ACE-2 Antibody, AF933, R&D systems (a Bio-Techne brand (Minneapolis, MN, USA)).

Techniques: Infection, Modification, Western Blot, Expressing, Mass Spectrometry, Quantitative RT-PCR

Journal: International Journal of Molecular Sciences

Article Title: tRNA Modifications: A Tale of Two Viruses—SARS-CoV-2 and ZIKV

doi: 10.3390/ijms26157479

Figure Lengend Snippet: ALKBH8 and CTU1 knockdown individually impairs SARS-CoV-2 and ZIKV infection. ( A ) Schematic showing shRNA-mediated knockdown approach targeting U34 ALKBH8 and CTU1 components of U34 modification pathway. The Western blot analysis of ACE2 expression in A549 cells with and without lentiviral vector expressing ACE2 (VLP ACE2 ). ( B ) Western blot validation of ALKBH8 and CTU1 knockdown efficiency with corresponding actin loading controls. Numbers indicate relative protein levels. ( C ) SARS-CoV-2 infection levels measured by RT-qPCR following knockdown of the indicated genes 24 h post-infection. ( D ) ZIKV infection levels measured by RT-qPCR following knockdown of the indicated genes 48 h post-infection.

Article Snippet: Seventy-two hours after transduction, accurate ACE2 expression was controlled by Western blots using anti-ACE2 antibody (Human ACE-2 Antibody, AF933, R&D systems (a Bio-Techne brand (Minneapolis, MN, USA)).

Techniques: Knockdown, Infection, shRNA, Modification, Western Blot, Expressing, Plasmid Preparation, Biomarker Discovery, Quantitative RT-PCR

Journal: Microbiology Spectrum

Article Title: Seasonal human coronaviruses OC43, 229E, and NL63 induce cell surface modulation of entry receptors and display host cell-specific viral replication kinetics

doi: 10.1128/spectrum.04220-23

Figure Lengend Snippet: Susceptibility of various cell lines to CPE following infection by HCoVs

Article Snippet: The following antibodies and isotypes were used to quantify the surface marker expression and receptor modulation in the uninfected (control) and infected cells: PE anti-human CD13, anti-human CD147 (isotype-control antibody mouse IgG1 κ, BioLegend); and anti-human CD326 (isotype-control antibody mouse IgG2a κ; BioLegend); human anti-ACE2 antibody (isotype-control antibody Goat IgG; R&D Systems) and anti-GD3, 9-O-acetyl (clone UM4D4; isotype-control antibody mouse IgM κ; Millipore Sigma).

Techniques: Infection

Journal: Microbiology Spectrum

Article Title: Seasonal human coronaviruses OC43, 229E, and NL63 induce cell surface modulation of entry receptors and display host cell-specific viral replication kinetics

doi: 10.1128/spectrum.04220-23

Figure Lengend Snippet: Phenotypic characterization of cell surface markers of OC43-infected cells. Phenotypic characterization of ( A ) uninfected (blue) and ( B ) OC43-infected HCT-8 cells (red). CD13, CD147, CD326, ACE2, and GD3 expression were probed by flow cytometry. ( C ) Histogram plots of control and infected HCT-8 cells relative to isotype control (gray). Histograms plots showing ( D ) percentage of cells expressing a given marker and ( E ) mean fluorescence intensity. Data in panels D and E represent the mean of two biological replicates for all antigens except GD3, where three biological replicates were carried out. Statistical analysis was performed with the multiple unpaired t -test with Welch’s correction. Only results that reached statistical significance were identified: * P ≤ 0.033, ** P ≤ 0.002, *** P ≤ 0.0001, **** P ≤ 0.0001.

Article Snippet: The following antibodies and isotypes were used to quantify the surface marker expression and receptor modulation in the uninfected (control) and infected cells: PE anti-human CD13, anti-human CD147 (isotype-control antibody mouse IgG1 κ, BioLegend); and anti-human CD326 (isotype-control antibody mouse IgG2a κ; BioLegend); human anti-ACE2 antibody (isotype-control antibody Goat IgG; R&D Systems) and anti-GD3, 9-O-acetyl (clone UM4D4; isotype-control antibody mouse IgM κ; Millipore Sigma).

Techniques: Infection, Expressing, Flow Cytometry, Control, Marker, Fluorescence

Journal: Microbiology Spectrum

Article Title: Seasonal human coronaviruses OC43, 229E, and NL63 induce cell surface modulation of entry receptors and display host cell-specific viral replication kinetics

doi: 10.1128/spectrum.04220-23

Figure Lengend Snippet: Phenotypic characterization of cell surface markers of 229E-infected cells. Phenotypic characterization of ( A ) uninfected (blue) and ( B ) 229E-infected MRC-5 cells (red). CD13, CD147, CD326, and ACE2 expression were probed by flow cytometry. ( C ) Histogram plots of control and infected MRC-5 cells relative to isotype control (gray). Histograms plots showing ( D ) percentage of cells expressing a given marker and ( E ) mean fluorescence intensity. Data in panels D and E represent the mean of three biological replicates, except for CD147 where two biological replicates were carried out. Statistical analysis was performed with the multiple unpaired t -test with Welch’s correction. Only results that reached statistical significance were identified: * P ≤ 0.033, ** P ≤ 0.002, *** P ≤ 0.0001, **** P ≤ 0.0001.

Article Snippet: The following antibodies and isotypes were used to quantify the surface marker expression and receptor modulation in the uninfected (control) and infected cells: PE anti-human CD13, anti-human CD147 (isotype-control antibody mouse IgG1 κ, BioLegend); and anti-human CD326 (isotype-control antibody mouse IgG2a κ; BioLegend); human anti-ACE2 antibody (isotype-control antibody Goat IgG; R&D Systems) and anti-GD3, 9-O-acetyl (clone UM4D4; isotype-control antibody mouse IgM κ; Millipore Sigma).

Techniques: Infection, Expressing, Flow Cytometry, Control, Marker, Fluorescence

Journal: Microbiology Spectrum

Article Title: Seasonal human coronaviruses OC43, 229E, and NL63 induce cell surface modulation of entry receptors and display host cell-specific viral replication kinetics

doi: 10.1128/spectrum.04220-23

Figure Lengend Snippet: Phenotypic characterization of cell surface markers of NL63-infected cells. Phenotypic characterization of ( A ) uninfected (blue) and ( B ) NL63-infected LLC-MK2 cells (red). CD13, CD147, CD326, and ACE2 expression were probed by flow cytometry. ( C ) Histogram plots of control and infected LLC-MK2 cells relative to isotype control (gray). Histograms plots showing ( D ) percentage of cells expressing a given marker and ( E ) mean fluorescence intensity. Data in panels D and E represent the mean of three biological replicates, except for CD13 where two biological replicates were carried out. Statistical analysis was performed with the multiple unpaired t -test with Welch’s correction. Only results that reached statistical significance were identified: * P ≤ 0.033, ** P ≤ 0.002, *** P ≤ 0.0001, **** P ≤ 0.0001.

Article Snippet: The following antibodies and isotypes were used to quantify the surface marker expression and receptor modulation in the uninfected (control) and infected cells: PE anti-human CD13, anti-human CD147 (isotype-control antibody mouse IgG1 κ, BioLegend); and anti-human CD326 (isotype-control antibody mouse IgG2a κ; BioLegend); human anti-ACE2 antibody (isotype-control antibody Goat IgG; R&D Systems) and anti-GD3, 9-O-acetyl (clone UM4D4; isotype-control antibody mouse IgM κ; Millipore Sigma).

Techniques: Infection, Expressing, Flow Cytometry, Control, Marker, Fluorescence

Journal: Microbiology Spectrum

Article Title: Seasonal human coronaviruses OC43, 229E, and NL63 induce cell surface modulation of entry receptors and display host cell-specific viral replication kinetics

doi: 10.1128/spectrum.04220-23

Figure Lengend Snippet: Soluble ACE2 protein and anti-ACE2 monoclonal blocking antibody inhibit NL63 infection in LLC-MK2 cells. ( A ) Treatment with soluble ACE2 or control protein ovalbumin at 5 and 10 mg/mL was pre-incubated with NL63 virus at MOI 0.1 (virus titer: 8.89 × 10 5 TCID 50 /mL) for 1 hour, and the protein and virus mixture complex was added to the LLC-MK2 cells. ( B ) Similarly, cells were incubated for 1 hour with human anti-ACE2 monoclonal blocking antibody (10, 40, and 120 µg/mL) or unrelated control antibody (anti-DC-SIGN; 40 µg/mL) followed by addition of NL63 virus (MOI 0.1). Five days post-infection, both culture supernatants and cell lysates were harvested for quantification of nucleocapsid (N) and spike (S) vRNA copies by ddPCR. Percent relative viral inhibition following treatment with (C) sACE2 or (D) anti-ACE2 monoclonal antibody compared to their respective untreated control. Data represent three biological replicates for sACE2 or four (anti-ACE2) with three technical replicates per experiment. Statistical analysis was performed using an unpaired t -test with Welch’s correction ( P < 0.05) relative to untreated control. n.s. denoted as no statistical difference; * P ≤ 0.033, ** P ≤ 0.002, *** P ≤ 0.0001, **** P ≤ 0.0001.

Article Snippet: The following antibodies and isotypes were used to quantify the surface marker expression and receptor modulation in the uninfected (control) and infected cells: PE anti-human CD13, anti-human CD147 (isotype-control antibody mouse IgG1 κ, BioLegend); and anti-human CD326 (isotype-control antibody mouse IgG2a κ; BioLegend); human anti-ACE2 antibody (isotype-control antibody Goat IgG; R&D Systems) and anti-GD3, 9-O-acetyl (clone UM4D4; isotype-control antibody mouse IgM κ; Millipore Sigma).

Techniques: Blocking Assay, Infection, Control, Incubation, Virus, Inhibition

Journal: Virus Evolution

Article Title: Deep mutational scanning of SARS-CoV-2 Omicron BA.2.86 and epistatic emergence of the KP.3 variant

doi: 10.1093/ve/veae067

Figure Lengend Snippet: Deep mutational scanning of the SARS-CoV-2 Omicron BA.2.86 RBD. (a) Diagram of the RBD substitutions that distinguish Omicron BA.2 from Wuhan-Hu-1 (top), and BA.2.86 from BA.2 (bottom). Italicized mutations in BA.2.86 indicate secondarily mutated (D339H, A484K) or reverted (R493Q) substitutions that originally changed from Wuhan-Hu-1, and dashed lines show propagation of BA.2. changes to BA.2.86. Wuhan-Hu-1 reference spike numbering is used throughout the manuscript. (b–d) Quality control of the BA.2.86 RBD site-saturation mutagenesis library as assessed by PacBio sequencing, illustrating the distribution of number of amino acid mutations per barcoded variant (b), the average number of mutations of each type across library variants (c), and the distribution of mutations across sites in the RBD over all variants (d). (e, f) FACS gates used to sort RBD + singlet cells for ACE2 titration (e) and RBD expression (f) deep mutational scanning experiments from one representative replicate. (g, h) Correlation in per-mutant deep mutational scanning measurements between independently barcoded replicate libraries for ACE2-binding affinity (g) and RBD expression (h) experiments.

Article Snippet: Induced cells were washed with phosphate buffered saline supplemented with bovine serum albumin (PBS-BSA , BSA 0.2 mg/l), split into 16-OD*ml aliquots, and incubated with biotinylated monomeric human ACE2 protein (ACROBiosystems AC2-H82E8) across a concentration range from 10 −6 to 10 −13 m at 1−log intervals, plus a 0 m sample.

Techniques: Control, Mutagenesis, PacBio Sequencing, Variant Assay, Titration, Expressing, Binding Assay

Journal: Virus Evolution

Article Title: Deep mutational scanning of SARS-CoV-2 Omicron BA.2.86 and epistatic emergence of the KP.3 variant

doi: 10.1093/ve/veae067

Figure Lengend Snippet: Effects of mutations in the BA.2.86 receptor-binding domain on ACE2-binding and RBD expression. (a) Heatmap illustrating the impacts of all mutations in the BA.2.86 RBD on ACE2-binding affinity as determined from FACS-seq experiments with yeast-displayed RBD mutant libraries. ACE2 contact residues (top row of yellow squares, bottom heatmap) defined as RBD residues with non-hydrogen atoms <5 Å from ACE2 in the BA.2.86 RBD structure (PDB 8QSQ; Liu et al. 2024 ). Antibody escape residues (bottom row of orange squares, bottom heatmap) defined as those with average >0.125 relative antibody escape from aggregated deep mutational scanning data ( Greaney et al. 2022a ). (b) Deep mutational scanning data from (a) mapped to the ACE2-bound BA.2.86 RBD structure (PDB 8QSQ; Liu et al. 2024 ), illustrating the average effect of mutations at a site (left), the maximal effect of any mutation at a site (center), or the effect of the single-codon deletion (right). Sites of interest are labeled, and ACE2 (key motifs only) is shown as transparent gray cartoon. (c) Heatmap illustrating the impacts of all mutations in the BA.2.86 RBD on yeast-surface expression levels, a proxy for folding and expression efficiency. (d) Scatterplot illustrating the average effect of mutations at each site on ACE2-binding affinity ( y -axis) versus RBD expression ( x -axis). Yellow points indicate direct structural contacts as in (a). Individual measurements from (a) and (c) are reported in , and an interactive version of these heatmaps is available at https://tstarrlab.github.io/SARS-CoV-2-RBD_DMS_Omicron-EG5-FLip-BA286/RBD-heatmaps/ .

Article Snippet: Induced cells were washed with phosphate buffered saline supplemented with bovine serum albumin (PBS-BSA , BSA 0.2 mg/l), split into 16-OD*ml aliquots, and incubated with biotinylated monomeric human ACE2 protein (ACROBiosystems AC2-H82E8) across a concentration range from 10 −6 to 10 −13 m at 1−log intervals, plus a 0 m sample.

Techniques: Binding Assay, Expressing, Mutagenesis, Labeling

Journal: Virus Evolution

Article Title: Deep mutational scanning of SARS-CoV-2 Omicron BA.2.86 and epistatic emergence of the KP.3 variant

doi: 10.1093/ve/veae067

Figure Lengend Snippet: Epistatic shifts in mutational effects on ACE2 binding. (a) Epistatic shift in the effects of mutations on ACE2 binding at each RBD position as measured in the Wuhan-Hu-1 [previously reported in ( Starr et al. 2022a )] or BA.2.86 background compared to those previously measured in Omicron BA.2 ( Starr et al. 2022b ). Shaded gray bars indicate sites of strong antibody escape, as defined in Fig. 2A . (b) Mutation-level plots of epistatic shifts between BA.2 and BA.2.86 at sites of interest. Each scatterplot shows the measured ACE2-binding affinity of each amino acid (plotting character) in the BA.2.86 versus BA.2. backgrounds. Horizontal and vertical red dashed lines mark the wildtype RBD affinities on each axis, and the diagonal gray dashed line indicates the additive (non-epistatic) expectation. Interactive plots enabling the comparison of all SARS-CoV-2 variants and scatterplots for all RBD sites are available at https://tstarrlab.github.io/SARS-CoV-2-RBD_DMS_Omicron-EG5-FLip-BA286/epistatic-shifts/ .

Article Snippet: Induced cells were washed with phosphate buffered saline supplemented with bovine serum albumin (PBS-BSA , BSA 0.2 mg/l), split into 16-OD*ml aliquots, and incubated with biotinylated monomeric human ACE2 protein (ACROBiosystems AC2-H82E8) across a concentration range from 10 −6 to 10 −13 m at 1−log intervals, plus a 0 m sample.

Techniques: Binding Assay, Mutagenesis, Comparison

Journal: Virus Evolution

Article Title: Deep mutational scanning of SARS-CoV-2 Omicron BA.2.86 and epistatic emergence of the KP.3 variant

doi: 10.1093/ve/veae067

Figure Lengend Snippet: Epistatic emergence of the KP.3 variant . (a) Cladogram showing relationships among select SARS-CoV-2 Omicron variants, with amino acid substitutions at positions 455, 456, and 493 indicated (other mutations not shown). (b) Triple mutant cycle diagram illustrating epistatic interactions between L455S, F456L, and Q493E underlying KP.3 variant evolution. Transparent points indicate duplicate measurements of each variant’s binding strength for human ACE2 (determined as the EC50 from titrations of monomeric human ACE2 over yeast-displayed RBD variants), and solid points and lines connect the averaged binding values for each genotype. Red-orange lines highlight the impact of introducing the Q493E mutation in different sequence backgrounds. Asterisk indicates expected triple-mutant binding affinity assuming additivity of the single-mutant effects as measured in the BA.2.86 wildtype background. (c) Subset of the sarbecovirus RBD sequence alignment showing unique combinations of residues at positions 455, 456, and 493 that have evolved across different sarbecoviruses. Sequence names are colored according to RBD phylogenetic clade as in Starr et al. (2022c ).

Article Snippet: Induced cells were washed with phosphate buffered saline supplemented with bovine serum albumin (PBS-BSA , BSA 0.2 mg/l), split into 16-OD*ml aliquots, and incubated with biotinylated monomeric human ACE2 protein (ACROBiosystems AC2-H82E8) across a concentration range from 10 −6 to 10 −13 m at 1−log intervals, plus a 0 m sample.

Techniques: Variant Assay, Mutagenesis, Binding Assay, Sequencing

Journal: Journal of the Renin-Angiotensin-Aldosterone System: JRAAS

Article Title: Serum activity of angiotensin converting enzyme 2 is decreased in patients with acute ischemic stroke

doi: 10.1177/1470320316661060

Figure Lengend Snippet: Serum ACE2 activity is significantly correlated with SBP in stroke-alert patients and healthy young adults, but not AIS patients. Correlation graphs of ACE2 activity and SBP among stroke-alert patients (a) and healthy young adults (b) as compared to stroke patients (c). Young adult blood plasma samples in panel (b) were from a biorepository established by Wegman et al., which were obtained from research participants undergoing baseline measurements. (d) Correlation graph of ACE activity and mRS at discharge from hospital among AIS patients. ACE2: angiotensin converting enzyme 2; AIS: acute ischemic stroke; mRS: modified Rankin score; RFU: relative fluorescence unit; SBP: systolic blood pressure.

Article Snippet: Reaction Km and Vmax were determined using control samples and recombinant human ACE2 (R&D Systems, Inc., #933-ZN-010) as a positive control, and all samples were run in duplicate.

Techniques: Activity Assay, Clinical Proteomics, Modification, Fluorescence

Journal: Journal of the Renin-Angiotensin-Aldosterone System: JRAAS

Article Title: Serum activity of angiotensin converting enzyme 2 is decreased in patients with acute ischemic stroke

doi: 10.1177/1470320316661060

Figure Lengend Snippet: Activity of ACE2 and ACE in serum is altered following stroke. For human serum, bar graphs are means ± SEM and represent enzyme activity levels of ACE2 (a) and ACE (c) from control, stroke-alert, or AIS patients at an average of 3.6 hours and again at 3 days after stroke. Individual differences and means ± SEM in ACE2 (b) and ACE (d) are shown. * P <0.05 versus control and † P <0.05 versus stroke-alert. ‡ P <0.05 versus AIS <6 hours. ACE: angiotensin converting enzyme; ACE2: angiotensin converting enzyme 2; AIS: acute ischemic stroke; RFU: relative fluorescence unit.

Article Snippet: Reaction Km and Vmax were determined using control samples and recombinant human ACE2 (R&D Systems, Inc., #933-ZN-010) as a positive control, and all samples were run in duplicate.

Techniques: Activity Assay, Control, Fluorescence

Journal: Journal of the Renin-Angiotensin-Aldosterone System: JRAAS

Article Title: Serum activity of angiotensin converting enzyme 2 is decreased in patients with acute ischemic stroke

doi: 10.1177/1470320316661060

Figure Lengend Snippet: Predictors of acute ischemic stroke by multiple linear regression analysis.

Article Snippet: Reaction Km and Vmax were determined using control samples and recombinant human ACE2 (R&D Systems, Inc., #933-ZN-010) as a positive control, and all samples were run in duplicate.

Techniques: Activity Assay