Biophysical Society Thematic Meeting | Ascona 2026

Mechanobiology of Infection

Poster Abstracts

7-POS Board 7 TRAFFICKING AND NANOSCALE ORGANIZATION OF STRUCTURAL PROTEINS DURING SARS-COV-2 PARTICLE ASSEMBLY MRITTIKA DASGUPTA Indian Institute of Technology, Delhi, Kusuma School of Biological Sciences, New Delhi, India Assembly of enveloped viruses is a highly coordinated process that integrates intracellular trafficking, membrane remodeling, and the spatiotemporal organization of viral structural proteins within host cells, governed by the biophysical properties of host membranes such as curvature, lipid composition, and compartmental identity. The objective of this study is to define the role of the SARS-CoV-2 Envelope (E) protein in regulating the trafficking and nanoscale organization of structural proteins during virion assembly. To address this, we employed a virus like particle (VLP) system to compare wild-type particles with those lacking E ( Δ E), using biochemical assays, super-resolution microscopy, and transmission electron microscopy. Loss of E significantly reduced the incorporation of major structural proteins, indicating impaired assembly efficiency. Super-resolution imaging revealed that E promotes membrane association and drives the formation of spatially organized nanoscale assemblies of structural proteins, whereas Δ E conditions resulted in perturbed subcellular localization and disrupted spatial patterning. Ultrastructural analysis demonstrated that wild-type particles exhibit uniform, spherical morphology, while Δ E particles are pleomorphic with aberrant envelope formation, consistent with defective membrane curvature generation and compromised particle integrity. These findings demonstrate that the E protein coordinates trafficking and membrane-associated organization of structural proteins, thereby modulating host membrane properties to enable efficient SARS-CoV-2 assembly and maturation.

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