Journal: mBio
Article Title: Targeting sphingolipid metabolism: inhibition of neutral sphingomyelinase 2 impairs coronaviral replication organelle formation
doi: 10.1128/mbio.00084-25
Figure Lengend Snippet: Artificially induced ROs by overexpressing a self-cleaving HCoV-229E nsp3-4 construct. ( A ) Schematic illustration of constructs generated to induce artificial HCoV-229E ROs upon transfection. The epitope tags used at the termini of the constructs are indicated as dots. The HA-nsp3-4-V5_K2481A construct contains an alanine substitution in the cleavage site of nsp3-4, therefore avoiding nsp3-mediated polyprotein cleavage. The HA-nsp3-4-V5_C1701A construct contains an alanine substitution that abrogates PL pro activity. ( B ) HEK-293T-ACE2 cells were transfected for 24 h with the indicated expression constructs, lysed, and HA-nsp3 and nsp4-V5-tagged proteins were detected using Western blot analysis. GAPDH served as a loading control. ( C ) Huh-7-ACE2 cells were transfected for 24 h with the indicated expression constructs, fixed, and stained using HA-specific (green) or V5-specific (red) antibodies. Subcellular localization was visualized by confocal microscopy using a Leica SP05. DAPI was used for staining of nuclei. Scale bars = 5 µm. ( D ) Huh-7-ACE2 cells were transfected with the indicated constructs, fixed 24 hours post-transfection, and analyzed via transmission electron microscopy analysis using a Zeiss LEO electron microscope. Scale bars = 500 nm.
Article Snippet: Human hepatoma cells (Huh-7; Japanese Collection of Research Bioresources cell bank), human embryonal kidney cells (HEK-293T; ATCC CRL-1573), and human lung adenocarcinoma cells (A549; ATCC CCL-185) overexpressing the ACE2 receptor (Huh-7-ACE2, HEK-293T-ACE2, A549-ACE2; kindly provided by Friedemann Weber, Institute of Virology, Justus Liebig University Giessen, Germany), A549 overexpressing CD13 and TMPRSS2 (A549-CD13; kindly provided by Krzysztof Pyrć, Małopolska Centre of Biotechnology, Jagiellonian University, Kraków, Poland), and primary human lung fibroblasts (MRC-5 cells; ATCC CCL-171) were grown in Dulbecco’s modified Eagle’s medium (DMEM, Invitrogen) and supplemented with 10% fetal calf serum (FCS) and antibiotics (100 U/mL of penicillin, 100 μg/mL of streptomycin and 0.5 μg/mL puromycin).
Techniques: Construct, Generated, Transfection, Activity Assay, Expressing, Western Blot, Control, Staining, Confocal Microscopy, Transmission Assay, Electron Microscopy, Microscopy