NPC1-regulated dynamic of clathrin-coated pits is essential for viral entry

Abstract

Viruses utilize cellular lipids and manipulate host lipid metabolism to ensure their replication and spread. Therefore, the identification of lipids and metabolic pathways that are suitable targets for antiviral development is crucial. Using a library of compounds targeting host lipid metabolic factors and testing them for their ability to block pseudorabies virus (PRV) and vesicular stomatitis virus (VSV) infection, we found that U18666A, a specific inhibitor of Niemann-Pick C1 (NPC1), is highly potent in suppressing the entry of diverse viruses including pseudotyped severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). NPC1 deficiency markedly attenuates viral growth by decreasing cholesterol abundance in the plasma membrane, thereby inhibiting the dynamics of clathrin-coated pits (CCPs), which are indispensable for clathrin-mediated endocytosis. Significantly, exogenous cholesterol can complement the dynamics of CCPs, leading to efficient viral entry and infectivity. Administration of U18666A improves the survival and pathology of PRV-and influenza A virus-infected mice. Thus, our studies demonstrate a unique mechanism by which NPC1 inhibition achieves broad antiviral activity, indicating a potential new therapeutic strategy against SARS-CoV-2, as well as other emerging viruses.

Pseudorabies Virus Inhibits Expression of Liver X Receptors to Assist Viral Infection

“…Our study demonstrated a mechanism by which PRV disturbed LXR expression to promote viral entry through modulation of cholesterol homeostasis. This is in accordance with our previous report that cholesterol is critical for CCP dynamics in PRV entry [ 26 ]. These data provide novel insights into the prevention and control of diverse viruses that require cholesterol-regulated CCP dynamics for viral entry.…”

“…Cholesterol is critical for PRV entry [ 26 ], so we examined cellular cholesterol content by filipin staining in PRV-infected and T0901317-treated cells. PRV infection significantly increased cellular cholesterol content ( Figure 5 A).…”

“…Our previous study suggested that Niemann–Pick C1 deficiency attenuates PRV entry by decreasing cholesterol abundance and by inhibiting CCP dynamics [ 26 ]. Therefore, we examined whether LXR agonists acted via a similar mechanism.…”

Extraintestinal Pathogenic Escherichia coli Utilizes Surface-Located Elongation Factor G to Acquire Iron from Holo-Transferrin

“…Subsequently, the cells were shifted to 37°C at 5% CO 2 for 1 h to allow for fluor-TF internalization. After washing, the cells were fixed, permeabilized, and blocked as described previously ( 62 ). The intracellular bacteria were labeled with rabbit anti-RS218 antiserum and TRITC-goat anti-rabbit IgG antibodies.…”

Antisense Oligonucleotide-Based Therapy of Viral Infections

“…However, cellular entry of SARS-CoV does not require NPC1 per se but rather relies on increased cathepsin L activity in NPC1-containing late endosomes or lysosomes [103]. Accordingly, recent studies demonstrated that an NPC1 inhibitor could suppress the cellular entry of pseudotyped SARS-CoV-2 [104,105]. Therefore, antisense strategies targeting NPC1 may treat and prevent human coronavirus infections.…”