Molecular Plant Pathology – Pathogen Profiles

Strawberry crinkle virus, a Cytorhabdovirus needing more attention from virologists

Karin I. Posthuma, Anthony N. Adams and Yiguo Hong 
Department of Entomology and Plant Pathology, Horticulture Research International, East Malling, Kent, ME19 6BJ, UK.

Taxonomic relationship:A member of nonsegmented, negative-sense, single-stranded RNA viruses of the genus Cytorhabdovirus (type member: Lettuce necrotic yellows virus), family Rhabdoviridae, order Mononegavirales. Members of the family Rhabdoviridae can infect vertebrates, invertebrates and plants.
Physical properties:Virions are bacilliform, 74-88 nm in diameter and 163-383 nm in length with surface projections probably composed of trimers of the glycoprotein G, occurring in the cytoplasm in either the coated or the uncoated form (Fig. 1). The nucleocapsid is enclosed in a host-derived envelope. Within the virion, the SCV genome consists of a single negative-sense single-stranded RNA molecule of approximately 13 kb.
Viral proteins:The SCV genome encodes at least five proteins: the nucleocapsid (N) protein (45 kDa), the matrix (M) protein (77 kDa), the nonstructural protein [Ns, 55 kDa, also known as phosphoprotein (P) ], the glycoprotein (G, 23 kDa) and the large (L) protein.
Hosts:The natural host range of SCV is limited to species of the genus Fragaria L. Experimental hosts include Physalis pubescens L., P. floridana Rydb., Nicotiana occidentalisN. glutinosa L. and N. clevelandi Gray. SCV also replicates in its insect vectors Chaetosiphon fragaefolii Cockerell and C. jacobi Hille Ris Lamberts. When injected as purified virus, SCV replicates in aphids Hyperomyzus lactucae (L.), Macrosiphon euphorbiae Thomas, Myzus ornatus Laing, Megoura viciaeBuckton, and Acyrthosiphoa pisum (Harris).