Coronaviruses (CoVs) rely heavily on host lipid metabolism for efficient replication, but the specific host pathways involved remain incompletely defined. Here, we identify the non-vesicular cholesterol transport protein GRAMD1C as a key host factor required for the replication of multiple coronaviruses across α, β, and δ genera, including TGEV, PEDV, HCoV-229E, SARS-CoV-2, MHV, and PDCoV. Mechanistically, GRAMD1C is recruited to the replication factory through its interaction with the viral nonstructural proteins 3 and 4 (nsp3 and nsp4). Transmission electron microscopy (TEM) analysis revealed that GRAMD1C facilitates the formation of replication double-membrane vesicles (DMVs). Further domain rescue and inhibitor experiments demonstrated that GRAMD1C's cholesterol transport activity is essential for viral replication. Moreover, GRAMD1C-deficient and inhibitor-treated mice exhibited reduced viral replication, underscoring its critical role in vivo. Collectively, our findings expand the current understanding of the importance of non-vesicular cholesterol transport in viral replication and highlight GRAMD1C as a promising broad-spectrum antiviral target.
Copyright: © 2026 Su et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.