The Coat Protein Is Dispensable for the Establishment of Systemic Infections by Pea Enation Mosaic Enamovirus

Abstract

Deletions in the coat protein (CP) open reading frame (ORF)-3 of pea enation mosaic enamovirus (PEMV) did not inhibit the systemic movement of PEMV. As early as 48 h postinoculation, truncated viral RNAs were detected in the roots and uninoculated leaves of infected plants. The detected concentrations of truncated RNAs varied significantly between experiments but were similar to those extracted from plants infected with wild-type (WT)-PEMV. Pea plants infected with CP-less mutants exhibited wilting and necrosis that appeared faster and were more severe than observed in infections with WT-PEMV. Moreover, the absence of the CP-ORF and its protein product did not affect the formation of either double-membrane bound vesicles or replication complexes characteristic of infections by PEMV. The potential role of these structures as the movement vehicles of the infectious entity of PEMV in plants is discussed.

Keywords

• luteovirus
• umbravirus