Endoplasmic reticulum: a focal point of Zika virus infection

Mohd Ropidi, Muhammad Izzuddin; Khazali, Ahmad Suhail; Nor Rashid, Nurshamimi; Yusof, Rohana

Although detailed mechanistic insights of virion assembly remains uncertain, recent study identified that ZIKV NS2A independently recruits viral (+)-ssRNA, NS2B-NS3, and unprocessed C-prM-Env complexes to the virus particle assembly site, possibly through NS2A oligomerization [39] . The same study postulates that virus particle assembly proceeds through NS2B-NS3 protease complex cleaving the recruited C-prM-Env complex. Cleaved capsid protein form nucleocapsid core with the viral RNA and capsid-dense lipid droplet; and subsequently, it is encapsulated by prM and Env proteins, which leads to eventual virion budding into the ER lumen [39] . Ultrastructural analyses within the dilated ER lumen consistently identified virus particles arranged in a two-dimensional paracrystalline array [32, 37] . This array is located in close proximity to the replication vesicles and is therefore largely comprised of fully assembled virions and viral-like particles (enveloped virions without viral genome) [37] .