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bioRxiv · 10.64898/2026.05.07.723438

Maturation-dependent structural dynamics and nanomechanical properties of dengue virus revealed by high-speed AFM and 3D force mapping

McArthur, S. J.·Umeda, K.·Kodera, N.
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Abstract

Although the maturation state of dengue virus (DENV) particles is a key determinant of their infectivity, maturation is unusually inefficient. Fully mature and immature DENV particles are well-studied; however, little is known about partially mature particles. Moreover, single-particle structural dynamics and nanomechanical properties are unknown. Here, we observe wildtype and immature DENV particles using a single-particle approach combining high-speed AFM (HS-AFM) and 3D force mapping (3DFM). HS-AFM shows that the conformations of each morphotype are heterogeneous and dynamic in liquid, particularly partially mature virions. Tracking immature prM-E spikes elucidates their dynamic movements, which show intraviral variation and constrained independence. 3DFM measurements suggest that internal DENV structure is also heterogeneous and undergoes maturation-dependent changes, with the nucleocapsid core not occupying the full internal volume of immature virions. This approach complements current structural virology techniques and adds a new dimension to our understanding of the structural properties of viruses.

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McArthur, S. J., Umeda, K., Kodera, N.. 2026-05-12. Maturation-dependent structural dynamics and nanomechanical properties of dengue virus revealed by high-speed AFM and 3D force mapping. https://doi.org/10.64898/2026.05.07.723438

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