A replication-competent chimera of plant and animal viruses.
Human, animal, fungal, and plant viruses encode papain-like proteinases that function in polyprotein processing, RNA synthesis, and virus-host interactions. To compare the functional profiles of diverse papain-like proteinases, we replaced a proteinase gene of the beet yellows virus (BYV) with those derived from equine arteritis virus (EAV), foot-and-mouth disease virus (FMDV), and the fungal virus CHV1. We found that, although each of the foreign proteinases efficiently processed the viral polyprotein, only the EAV proteinase supported vigorous replication of the chimeric BYV in plant protoplasts. This result demonstrated that the proteinases of BYV and EAV, but not FMDV or CHV1, provide a function that is critical for genome replication and that is separable from polyprotein processing. Further characterization of the BYV-EAV chimera revealed that BYV proteinase is also required for virus invasion and cell-to-cell movement. Thus, the same viral protein can combine both replication-related functions shared by plant and animal viruses and specialized functions in virus-host interactions.
Peng
Chih-Wen
CW
Department of Botany and Plant Pathology, Center for Gene Research and Biotechnology, Oregon State University, Corvallis, OR 97331, USA.
Peremyslov
Valera V
VV
Snijder
Eric J
EJ
Dolja
Valerian V
VV
D000818:Animals; D017790:Closterovirus / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D010450:Endopeptidases / Q000235:genetics* / Q000378:metabolism*; D007240:Equartevirus / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D029544:Foot-and-Mouth Disease Virus / Q000201:enzymology / Q000235:genetics; D010944:Plants / Q000821:virology; D011523:Protoplasts / Q000821:virology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication
D011993:Recombinant Fusion Proteins; D010450:Endopeptidases