The Complete Nucleotide Sequence and Genomic Organization of Citrus Leprosis Associated Virus, Cytoplasmatic type (CiLV-C)

Abstract

The Citrus leprosis disease (CiL) is associated to a virus (CiLV) transmitted by Brevipalpus spp. mites (Acari: Tenuipalpidae). CiL is endemic in Brazil and its recently spreading to Central America represents a threat to citrus industry in the USA. Electron microscopy images show two forms of CiLV: a rare nuclear form, characterized by rod-shaped naked particle (CiLV-N) and a common cytoplasmic form (CiLV-C) associated with bacilliform-enveloped particle and cytoplasmic viroplasm. Due to this morphological feature, CiLV-C has been treated as Rhabdovirus-like. In this paper we present the complete nucleotide sequence and genomic organization of CiLV-C. It is a bipartite virus with sequence similarity to ssRNA positive plant virus. RNA1 encodes a putative replicase polyprotein and an ORF with no known function. RNA2 encodes 4 ORFs. pl5, p24 and p61 have no significant similarity to any known proteins and p32 encodes a protein with similarity to a viral movement protein. The CiLV-C sequences are associated with typical symptoms of CiL by RT-PCR. Phylogenetic analysis suggests that CiLV-C is probably a member of a new family of plant virus evolutionarily related to Tobamovirus.

An annotated list of ornamentals naturally found infected by Brevipalpus mite-transmitted viruses

“…It was found that two distinct viruses, based on cytopathic effects, both transmitted by B. phoenicis, respectively cytoplasmic (CiLV-C) and nuclear (CiLV-N), cause leprosis symptoms, being the CiLV-C the prevalent . The complete sequence of the genome of CiLV-C was obtained (Pascon et al, 2006) being a bipartite positive sense ssRNA distinct from known viruses. As a consequence, a new genus, Cilevirus, was proposed for this virus (Locali-Fabris et al, 2006).…”

Present status of citrus leprosis in Argentina and Paraguay

“…It was also found that leprosis symptoms may be caused by two distinct viruses based on the cytopathic effects Rodrigues et al, 2003), both transmitted by Brevipalpus mites: the rare nuclear type (Citrus leprosis virus N-CiLV-N), a likely member of the Dichorhabdovirus genus, whose type member is Orchid fleck virus (OFV) (Kondo et al, 2006); and the prevalent and more aggressive cytoplasmic type Citrus leprosis virus C (CiLV-C). Its genome was entirely sequenced (Locali-Fabris et al, 2006;Pascon et al, 2006) and it was accepted as the type-member Present status of citrus leprosis in Argentina and Paraguay of the new genus Cilevirus (Locali-Fabris et al, 2006;Carstens, 2010;Locali-Fabris et al, 2012), resulting in molecular (Locali et al, 2003) and immunochemical tools (Calegario et al, 2013) for CiLV-C detection. Although symptoms in the fruits and barks caused by CiLV-C and CiLV-N are undistinguishable, there is a slight but consistent difference in leaf symptoms: CiLV-N causes smaller lesions with a dark central spot surrounded by a bright yellow halo while lesions caused by CiLV-C may reach larger size and present a light green color commonly with one or more gummy rings (Bastianel et al, 2010).…”

Resposta diferencial de espécies e de híbridos de citros à leprose

“…Entretanto, o seqüenciamento completo de seu genoma (Locali-Fabris et al, 2006;Pascon et al, 2006) indicou se tratar de um vírus totalmente diferente daqueles seqüenciados até então e resultou na proposta de se criar um novo gênero de vírus, Cilevirus, tendo o CiLV como membro-tipo (Locali-Fabris et al, 2006). Um teste molecular confiável e sensível para a diagnose da doença indica que as duas formas do CiLV apresentam genomas totalmente distintos .…”