New insights into tobacco mosaic virus: stability, disassembly and uncoating

Tobacco mosaic virus (TMV) serves as a key model in both virology and nanotechnology, admired for its robust structure and ease of assembly. While the mechanical resistance of TMV has attracted interest for nanostructure applications [1], the intricate details of its disassembly mechanics remain poorly understood. In this study, we integrate three key aspects of TMV behavior: its mechanical resilience, its thermal stability and the role of genome-protein interactions. By combining nanoindentation experiments with coarse-grain and finite elements simulations [2], we investigate how the viral capsid disassembles as a function of the force applied. Which reveals that the central cavity plays a critical role in the distribution of mechanical stress. We also heated TMV up to 175ºC and found almost no structural degradation. Beyond this temperature, its height follows a sigmoidal curve until its complete degradation at 250ºC. Additionally, we explore how the specific nucleotide sequence of the TMV RNA affects the weakening of specific regions during mechanical disassembly [3]. Using Atomic Force Microscopy (AFM), we correlate the formation of rifts along the capsid with the trimers in the genomic sequence, shedding light on how these interactions contribute to the mechanical stability of the virus. Together, this combined approach provides a deeper understanding of the structural integrity of TMV and the factors that govern its disassembly process.