Poxvirus under the eyes of electron microscope

Abstract

Zoonotic poxvirus infections pose significant threat to human health as we have witnessed recent spread of monkeypox. Therefore, insights into molecular mechanism behind poxvirus replication cycle are needed for the development of efficient antiviral strategies. Virion assembly is one of the key steps that determine the fate of replicating poxviruses. However, in-depth understanding of poxvirus assembly is challenging due to the complex nature of multi-step morphogenesis and heterogeneous virion structures. Despite these challenges, decades of research have revealed virion morphologies at various maturation stages, critical protein components and interactions with host cell compartments. Transmission electron microscopy has been employed as an indispensable tool for the examination of virion morphology, and more recently for the structure determination of protein complexes. In this review, we describe some of the major findings in poxvirus morphogenesis and the contributions of continuously advancing electron microscopy techniques.

Ultrastructural analysis of monkeypox virus replication in Vero cells

“…[8][9][10] Despite the public health relevance of MPXV, some biological aspects, such as particles' morphology and the virus replication cycle, remain to be further established compared to other closely related poxviruses, like vaccinia virus (VACV) and variola virus (VARV). [11][12][13][14][15][16] Few studies have presented transmission electron microscopy (TEM) images of MPXV particles, 6,17,18 and to the best of our knowledge, there is no available microscopy analysis of different steps of the MPXV replication cycle. We here present a microscopy analysis of the replication cycle of an MPXV isolate obtained from a patient lesion in June 2022, Brazil.…”

Review of virological methods for laboratory diagnosis and characterization of monkeypox virus (MPXV): lessons learned from the 2022 Mpox outbreak

“…Mature OPVs generally have an ovoid or brick-shaped morphology, ranging from 220 to 450 nm in length and 140 to 260 nm in width, making them among the largest known animal viruses. However, OPVs cannot be distinguished morphologically (75,80).…”

An overview on monkeypox virus: Pathogenesis, transmission, host interaction and therapeutics

“…MPV is one of the largest and most highly complex viruses (Barreto-Vieira and Barth, 2015) demonstrating a brick-shaped structure with a length of 220 -450 nm and a width ranging from 140 -260 nm (Hyun, 2022). It has four components: core, lateral bodies, outer membrane, and outer lipoprotein envelope (Sklenovska, 2020).…”