COVID-19 researchGene: NPC1
Evidence Summary from Illumina curation team (Alison Coffey and Julie Taylor): NPC1 encodes a polytopic protein that resides in the limiting membrane of late endosomes and lysosomes (LE/LY) and mediates distribution of lipoprotein-derived cholesterol in cells (Cote et al. (2011). NPC1 expression is critical for filovirus infection (EboV and MarV) and the mechanism of infection is not dependent on NPC1 cholesterol transport activity (Carette et al. 2011). Structural studies demonstrate that the C-domain of NPC1 binds to the primed EBOV glycoprotein (Wang et al. 2016; Gong et al. 2016).
PMID 21866103: Carette et al. (2011)
Genome-wide haploid genetic screen was performed in primary fibroblasts derived from human Niemann-Pick type C1 disease patients to identify host factors required for Filovirus infection. These cells are resistant to infection by EboV and MarV but remain fully susceptible to other unrelated viruses (Figure 2A, B). Resistance of NPC1-deficient cells was not caused by cholesterol transport defects (Fig S8). Infection in these cells was restored by expression of wild type NPC1 (Figure 2C). Similar results were observed in NPC1-null Chinese hamster ovary (CHO) cells, with loss of NPC1 conferring complete resistance to viral infection (Figure S6D) that was reversed by expression of human NPC1 (Figure S6E). Electron micrographs of NPC1 mutant cells infected with rVSV-GP-EboV indicate that NPC1 is required in downstream process in filovirus entry leading to viral membrane fusion and escape from the lysosomal compartment. Knockdown of NPC1 in HUVEC diminished infection by filoviruses (Figure 4D and S18) suggesting that NPC1 is critical for authentic filovirus infection. Furthermore, NPC1+/+ mice rapidly succumb to infection with either filovirus while NPC1−/+ mice were largely protected (Figure 4E).
PMID 2186610: Cote et al. (2011)
HeLa cells treated with benzylpiperazine adamantane diamide-derived compounds (3.0 and 3.47) developed cytoplasmic vacuoles indicating that that they target one or more proteins involved in regulation of cholesterol uptake in cells. CHO cells lacking NPC1 were completely resistant to infection by this virus and infection of these cells was fully restored when NPC1 was expressed. NPC1 expression but not NPC1-dependent cholesterol transport activity is essential for EboV infection (Fig 2c). 3.0-derived compounds inhibit EboV infection by interfering with binding of cleaved glycoprotein to NPC1 (Fig 4).
PMID 26771495: Wang et al. (2016)
The crystal structure of the primed glycoprotein (GPcl) of Ebola virus and domain C of NPC1 (NPC1-C) demonstrates that the NPC1-C binds to the primed EBOV GP (Fig 1, 3). Further, it suggests that a membrane-fusion-priming conformational change occurs in GPcl or the binding of GPcl, and this is a unique feature for all the filoviruses. NPC1-interacting compound 3.47 competitively blocks the primed GP binding to the membrane probably binds to the two protruding loops of NPC1-C. Compound U18666A binds to a different site on NPC1 causing endosomal calcium depletion. Furthermore, peptide inhibitors or small molecules, which can easily penetrate the cell membrane and reach the primed GP in the late endosomes could also act as potential therapeutic agents.
PMID 27238017: Gong et al. (2016)
Full-length human NPC1 and a low-resolution reconstruction of NPC1 in complex with the cleaved glycoprotein (GPcl) of EBOV was determined by single-particle electron cryomicroscopy. NPC1 contains 13 transmembrane segments (TMs) and three lumenal domains, A (NTD), C, and I. TMs 2–13 exhibit a typical resistance-nodulation-cell division fold, among which TMs 3–7 constitute the sterol-sensing domain conserved in several proteins involved in cholesterol metabolism and signaling. EBOV-GPcl binds to NPC1 through the domain C.
Created: 28 May 2020, 3:23 p.m. | Last Modified: 28 May 2020, 3:23 p.m.
Panel Version: 0.348
Identified through an OMIM search for potential viral susceptibility genes, and subsequently triaged/reviewed by Illumina curation team.
Created: 28 May 2020, 12:36 p.m. | Last Modified: 28 May 2020, 12:36 p.m.
Panel Version: 0.336
gene: NPC1 was added gene: NPC1 was added to COVID-19 research. Sources: Expert list,OMIM,Expert Review Amber Mode of inheritance for gene: NPC1 was set to Unknown