HCF-1 encoded by baculovirus AcMNPV is required for productive nucleopolyhedrovirus infection of non-permissive Tn368 cells

Abstract

Baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) replicates in both Spodoptera frugiperda Sf21 and Trichoplusia ni Tn368 cells, whereas AcMNPV defective in hcf-1 (host cell-factor 1) gene productively infects only Sf21 cells, indicating that HCF-1 is indispensable for the AcMNPV productive infection of Tn368 cells. Here, we demonstrated that HCF-1 protein transiently expressed in Tn368 cells promotes the DNA synthesis of Hyphantria cunea MNPV (HycuMNPV), Orygia pseudotsugata MNPV and Bombyx mori NPV, which are normally unable to replicate in Tn368 cells. We also demonstrated that a recombinant HycuMNPV harboring the hcf-1 gene successfully replicates in Tn368 cells, generating substantial yields of progeny viruses and polyhedra. These results indicate that HCF-1 encoded by AcMNPV is an essential viral factor for productive NPV infection of Tn368 cells. Taken together with the previous findings on HRF-1 (host range factor 1), the present results provide strong evidence that viral genes acquired through horizontal gene transfer play an important role in baculovirus evolution, serving to expand the host range of baculoviruses.

Carbohydrate metabolism is a determinant for the host specificity of baculovirus infections

“…Such factors also include HRF-1 ( Thiem et al., 1996 ) and HCF-1 ( Tachibana et al., 2017 ), which enhance viral DNA replication and viral protein synthesis in certain cell lines. These studies focused on how viral factors influence the viral multiplication process in a host and revealed that the functionality of a single viral factor may not be able to ease the constraints for all nucleopolyhedroviruses (NPVs) in a nonpermissive host ( Tachibana et al., 2017 ). A permissive and nonpermissive host may exert different effects on a virus.…”

Genomic sequencing of Troides aeacus nucleopolyhedrovirus (TraeNPV) from golden birdwing larvae (Troides aeacus formosanus) to reveal defective Autographa californica NPV genomic features

“…Two genes that encode HCF-1 and APSUP were described as the host range determination factors in baculoviruses [89, 90]. It has been demonstrated that the AcMNPV HCF-1 protein is an essential viral factor for the productive NPV infection of TN-368 cells [93, 94]. Recently, a novel anti-apoptotic protein, APSUP, was identified in LdMNPV [95]; moreover, it has been demonstrated that the full-length Ld-Apsup could work against the apoptosis of Ld652Y cells induced by exposure to actinomycin D and UV and could interact with Ld-Dronc to prevent cells from undergoing apoptosis.…”

Methyl-Beta-Cyclodextrin-Induced Macropinocytosis Results in Increased Infection of Sf21 Cells by Bombyx Mori Nucleopolyhedrovirus

“…A notable factor is host cell-specific factor-1 ( hcf-1 ), which is absent in the BmNPV genome [3]. Hcf-1 is required for productive AcMNPV infections in nonpermissive Tn368 cells [34,35]; HCF-1 is an early protein that localizes to the cell nucleus [36], and promotes the replication of recombinant BmNPV in nonpermissive Tn368 cells [37]. In addition, GP64 has been identified as an AcMNPV and BmNPV host range determinant [1] and AcMNPV GP64 mediates BmNPV replication in Sf9 cells [4], thus, further work is needed to improve BmNPV infections in nonpermissive cells.…”