Analysis of the Cell Type-Dependence on the Arenavirus Z-Mediated Virus-Like Particle Production

Abstract

Several arenaviruses are highly pathogenic to humans, causing hemorrhagic fever. Discovery of anti-arenavirus drug candidates is urgently needed, although the molecular basis of the host-and organ-specific pathogenicity remains to be fully elucidated. The arenavirus Z protein facilitates production of virus-like particles (VLPs), providing an established method to assess virus budding. In this study, we examined the efficiency of VLP production by solely expressing Z protein of several different arenaviruses. In addition, we analyzed the role of the late (L)-domain of the arenavirus Z protein, which is essential for the interaction with ESCRT proteins, in VLP production among different cell lines. VLP assay was performed using Z proteins of Junín virus (JUNV), Machupo virus (MACV), Tacaribe virus (TCRV), Latino virus (LATV), Pichinde virus (PICV), and Lassa virus (LASV) in six different cell lines: HEK293T, Huh-7, A549, Vero76, BHK-21, and NIH3T3 cells. JUNV, MACV, and LASV Z proteins efficiently produced VLPs in all tested cell lines, while the efficiencies of VLP production by the other arenavirus Z proteins were cell typedependent. The contribution of the L-domain(s) within Z protein to VLP production also highly depended on the cell type. These results suggested that each arenavirus has its own particle-production mechanism, which is different among the cell types.

Exosomal transmission of viruses, a two-edged biological sword

“…It has been indicated that the activation of P (T/S)AP motifs in the HRS subunit of ESCRT-0 can recruit ESCRT-1 TSG101 via binding of the P(T/S) AP motif with the UEV domain of TSG101 [ 152 ]. The similar structure of the P (T/S) AP motif has been indicated within viral Gag protein from Retroviridiae (such as HIV and murine leukemia virus), Z proteins of Arenaviridae (Lassa virus and lymphocytic choriomeningitis virus), VP40 proteins of Filoviridae (Ebola virus and Marburg virus), and M (Matrix) proteins of Rhabdoviridae (vesicular stomatitis virus and rabies virus) [ 153 – 157 ]. These factors can activate TGG101, leading to the participation of the ESCRT complex at the site of virus entry [ 149 ].…”

“…The interaction promotes the ubiquitylation using NEDD4, as an ESCRT auxiliary protein, leading to the sorting of proteins into the MVBs [ 162 ]. Of note, a PPXY-like motif exists in several viruses from different families such as Retroviridiae, Rhabdoviridae [ 157 ], Arenaviridae [ 153 ], Filoviridae [ 156 ], Reoviridae [ 149 ], Hepadnavirideae [ 149 ], and Paramyxoviridae [ 159 ]. Similarly, the interaction of PPXY-NEDD4 increases the budding of the virus into the MVBs.…”

A Review Study of the Participation of Late Domains in Sorting and Transport of Viral Factors to Exosomes

“…Another important fact with arenaviruses is that most of these have been found a late domain, in the original arenaviruses, as mentioned, the Lassa virus contains two late domains PTAP and PPXY, while the Lujo virus only shows PSAP. Modern viruses such as Junin, Machupo, Guanarito, Sabia, and Chapare contain the PT/SAP domain and in this same context of viruses, it was found that the White Water Arroyo virus (WWAV) and Pichinde virus contain overlapping domains of PT/SAP and motifs similar to PPPY, with PT/SAPPY similar to those seen with Ebola [ 84 , 85 ]. The Hepatitis A virus was recently found to contain in its VP2 protein the YPX n L domain, and replacing Leu with Ala in the late domain eliminates virus release but does not alter viral assembly.…”

The Virus–Host Interplay in Junín Mammarenavirus Infection

“…In addition to this, the fact that the sole expression of Z protein induces the release of VLPs in the absence of other viral components [95,96,185], allowed the discrete study of viral morphogenesis and/or egress, independently of viral entry and replication [93,97,110,181]. Of note, it has been recently tested that JUNV Z efficiently produces VLPs in a variety of cell lines, unlike TCRV, which showed limited cell-type restrictions for the budding process [245]. In sum, all these cell-based systems described above have strongly helped to dissect different aspects of the viral life cycle of JUNV and related arenaviruses and have provided insights of JUNV interaction with cell host factors.…”