title: Identification and characterisation of a highly divergent geminivirus: evolutionary and taxonomic implications.
abstract: During a large scale "non a priori" survey in 2010 of South African plant-infecting single stranded DNA viruses, a highly divergent geminivirus genome was isolated from a wild spurge, Euphorbia caput-medusae. In addition to being infectious in E. caput-medusae, the cloned viral genome was also infectious in tomato and Nicotiana benthamiana. The virus, named Euphorbia caput-medusae latent virus (EcmLV) due to the absence of infection symptoms displayed by its natural host, caused severe symptoms in both tomato and N. benthamiana. The genome organisation of EcmLV is unique amongst geminiviruses and it likely expresses at least two proteins without any detectable homologues within public sequence databases. Although clearly a geminivirus, EcmLV is so divergent that we propose its placement within a new genus that we have tentatively named Capulavirus. Using a set of highly divergent geminiviruses genomes, it is apparent that recombination has likely been a primary process in the genus-level diversification of geminiviruses. It is also demonstrated how this insight, taken together with phylogenetic analyses of predicted coat protein and replication associated protein (Rep) amino acid sequences indicate that the most recent common ancestor of the geminiviruses was likely a dicot-infecting virus that, like modern day mastreviruses and becurtoviruses, expressed its Rep from a spliced complementary strand transcript.
authors.affiliation: CIRAD/UMR BGPI, TA A54/K, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France; INRA/UMR, BGPI, TA A54/K, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France.
authors.forename: Pauline
authors.initials: P
authors.lastname: Bernardo
authors.forename: Michael
authors.initials: M
authors.lastname: Golden
authors.forename: Mohammad
authors.initials: M
authors.lastname: Akram
authors.lastname: Naimuddin
authors.forename: Nagaswamy
authors.initials: N
authors.lastname: Nadarajan
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Fernandez
authors.forename: Martine
authors.initials: M
authors.lastname: Granier
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Rebelo
authors.forename: Michel
authors.initials: M
authors.lastname: Peterschmitt
authors.forename: Darren P
authors.initials: DP
authors.lastname: Martin
authors.forename: Philippe
authors.initials: P
authors.lastname: Roumagnac
mesh_terms: D028481:Euphorbia / Q000821:virology*; D019143:Evolution, Molecular; D017791:Geminiviridae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D016679:Genome, Viral; D018551:Solanum lycopersicum / Q000821:virology; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology*; D011995:Recombination, Genetic; D014026:Nicotiana / Q000821:virology; D014764:Viral Proteins / Q000235:genetics
chemical_list: D014764:Viral Proteins
keywords: DNA viruses; Evolution; Geminivirus; Phylogenetic analysis; Plant viruses; Taxonomy