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English: Infection of insect cells with Oryctes rhinoceros nudivirus (OrNV). (A) Stages of infection. (A1) Uninfected cell with intact nucleus. (A2) At midinfection, few virions (white arrows) surrounded by newly evolved vesicles (arrowheads) are observed inside the nucleus. (A3) In late infection the nuclear membrane which appears slightly distorted undergoes major changes to assist the assembly and the transport of virions. (A4) Cell lysis occurs around 72 h postinfection (hpi). Scale bar, 1,000 nm. (B) Comparison of nucleus and cytoplasmic organelles in OrNV-infected cells to uninfected cells. (B1) Low magnification of uninfected HA cell. High magnification of the inset (B5) shows that mitochondria, Golgi bodies, and ER remain intact in uninfected HA cells. (B2) HA cells infected with (low dose) OrNV at 16 hpi. While normal Golgi and ER are seen at a higher magnification (B6), the mitochondrial structures appear to be affected. Large MMV are also observed in the cytoplasm when virion replication and budding from plasma membrane peaked. (B3) OrNV-infected cells at 72 hpi (high dose). At a higher magnification (B7), the cytoplasm seems to be less electron dense, and organelles such as Golgi bodies and the ER seem to be disrupted. (B4) Infected HA cells resembling the late infection phase. Inset, at a high magnification (B8), shows no evident intact Golgi or ER structures. The scale bar of low-magnification micrographs (B1 to B4) represents 1,000 nm. The scale bar of images from inset (B5 to B8) represents 500 nm. (C) Time course of OrNV infection showing the evolution of viral titers and the concomitant decrease in viable cell density postinfection. (D) Cryo-EM of OrNV shed into the extracellular space showing the capsid surrounded by a thick envelope and its segmentation (right panel). Scale bar, 50 nm.