Characterization of the Lassa virus matrix protein Z: electron microscopic study of virus-like particles and interaction with the nucleoprotein (NP).
Lassa virus is the causative agent of a hemorrhagic fever endemic in west Africa. The RNA genome of Lassa virus encodes the glycoprotein precursor GP-C, a nucleoprotein (NP), the viral polymerase L and a small protein Z (11 kDa). Here, we analyze the role of Z protein for virus maturation. We have recently shown that expression of Z protein in the absence of other viral proteins is sufficient for the release of enveloped Z-containing particles. In this study, we examined particles secreted into the supernatant of a stably Z protein-expressing CHO cell line by electron microscopy. The observed Z-induced virus-like particles did not significantly differ in their morphology and size from Lassa virus particles. Mutation of two proline-rich domains within Z which are known to drastically reduce the release of virus-like particles, had no effect on the cellular localization of the protein nor on its membrane-association. Furthermore, we present evidence that Z interacts with the NP. We assume that Z recruits NP to cellular membranes where virus assembly takes place. We conclude from our data that Lassa virus Z protein plays an essential role in Lassa virus maturation.
Eichler
Robert
R
Institut für Virologie der Philipps-Universität Marburg, Robert-Koch-Strasse 17, D-35037 Marburg, Germany.
Strecker
Thomas
T
Kolesnikova
Larissa
L
ter Meulen
Jan
J
Weissenhorn
Winfried
W
Becker
Stephan
S
Klenk
Hans Dieter
HD
Garten
Wolfgang
W
Lenz
Oliver
O
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D018050:Arenavirus / Q000235:genetics; D001665:Binding Sites; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure*; D016679:Genome, Viral; D007836:Lassa virus / Q000235:genetics / Q000648:ultrastructure*; D008969:Molecular Sequence Data; D009154:Mutation; D009698:Nucleoproteins / Q000378:metabolism* / Q000648:ultrastructure; D012367:RNA, Viral / Q000235:genetics; D016601:RNA-Binding Proteins; D016415:Sequence Alignment; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D014763:Viral Matrix Proteins / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure*
D002352:Carrier Proteins; D009698:Nucleoproteins; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D014763:Viral Matrix Proteins; C487631:protein Z, Lassa virus