title: Ebola virus VP40 late domains are not essential for viral replication in cell culture.
abstract: Ebola virus particle formation and budding are mediated by the VP40 protein, which possesses overlapping PTAP and PPXY late domain motifs (7-PTAPPXY-13). These late domain motifs have also been found in the Gag proteins of retroviruses and the matrix proteins of rhabdo- and arenaviruses. While in vitro studies suggest a critical role for late domain motifs in the budding of these viruses, including Ebola virus, it remains unclear as to whether the VP40 late domains play a role in Ebola virus replication. Alteration of both late domain motifs drastically reduced VP40 particle formation in vitro. However, using reverse genetics, we were able to generate recombinant Ebola virus containing mutations in either or both of the late domains. Viruses containing mutations in one or both of their late domain motifs were attenuated by one log unit. Transmission and scanning electron microscopy did not reveal appreciable differences between the mutant and wild-type viruses released from infected cells. These findings indicate that the Ebola VP40 late domain motifs enhance virus replication but are not absolutely required for virus replication in cell culture.
authors.affiliation: Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Dr., Madison, WI 53706, USA.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Neumann
authors.forename: Hideki
authors.initials: H
authors.lastname: Ebihara
authors.forename: Ayato
authors.initials: A
authors.lastname: Takada
authors.forename: Takeshi
authors.initials: T
authors.lastname: Noda
authors.forename: Darwyn
authors.initials: D
authors.lastname: Kobasa
authors.forename: Luke D
authors.initials: LD
authors.lastname: Jasenosky
authors.forename: Shinji
authors.initials: S
authors.lastname: Watanabe
authors.forename: Jin H
authors.initials: JH
authors.lastname: Kim
authors.forename: Heinz
authors.initials: H
authors.lastname: Feldmann
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kawaoka
mesh_terms: D000818:Animals; D002460:Cell Line; D029043:Ebolavirus / Q000502:physiology*; D006801:Humans; D009698:Nucleoproteins / Q000737:chemistry* / Q000502:physiology; D017434:Protein Structure, Tertiary; D013329:Structure-Activity Relationship; D014758:Viral Core Proteins / Q000737:chemistry* / Q000502:physiology; D014779:Virus Replication
chemical_list: D009698:Nucleoproteins; D014758:Viral Core Proteins; C084819:nucleoprotein VP40, Ebola virus