Turnip curly top virus, a highly divergent geminivirus infecting turnip in Iran

Rob W. Briddon, Jahangir Heydarnejad, Fakhrosadat Khosrowfar, Hossain Massumi, Darren P. Martin, Arvind Varsani

Research output: Contribution to journalArticle

38 Scopus citations

Abstract

From 2006 onwards turnip crops in Fars province, Iran, have been noted with unusual leaf curling and vein swelling symptoms which are characteristic of the leafhopper-transmitted viruses of the genus Curtovirus (family Geminiviridae). Rolling circle amplification was used to clone viruses from five turnip isolates exhibiting leaf curl symptoms. Analysis of the sequences showed them to have >93% sequence identity and to be distinct from all other geminiviruses previously characterised. Analysis of the sequence of this virus, for which we propose the name Turnip curly top virus (TCTV), showed it to have a genome arrangement in the complementary-sense similar to that of curtoviruses (consisting of four overlapping genes) but only two open reading frames in the virion-sense (the curtoviruses encode three). The complementary-sense genes are homologous to those of curtoviruses but show little sequence identity to their curtovirus homologs, with the exception of the product of the C4 open reading frame (ORF) which shows ∼70.6% amino acid sequence identity to the C4 of the North American curtoviruses, Pepper curly top virus and Beet mild curly top virus. For curtoviruses the C4 protein is a symptom determinant, which likely explains the similarity of TCTV symptoms to those of curtoviruses. In the virion-sense the predicted product of the V2 ORF of TCTV shows no significant similarity with any proteins in the databases whereas the product of the V1 ORF (encoding the coat protein [CP] of geminiviruses) shows low levels of sequence identity to the CPs of curtoviruses. These findings show TCTV to be a highly divergent geminivirus with similarities to viruses of the genus curtovirus. The significance of these findings, particularly the taxonomic implications are discussed.

Original languageEnglish (US)
Pages (from-to)169-175
Number of pages7
JournalVirus research
Volume152
Issue number1-2
DOIs
StatePublished - Sep 1 2010
Externally publishedYes

Keywords

  • Curtovirus
  • Geminivirus
  • Turnip

ASJC Scopus subject areas

  • Cancer Research
  • Virology
  • Infectious Diseases

Fingerprint Dive into the research topics of 'Turnip curly top virus, a highly divergent geminivirus infecting turnip in Iran'. Together they form a unique fingerprint.

  • Cite this

    Briddon, R. W., Heydarnejad, J., Khosrowfar, F., Massumi, H., Martin, D. P., & Varsani, A. (2010). Turnip curly top virus, a highly divergent geminivirus infecting turnip in Iran. Virus research, 152(1-2), 169-175. https://doi.org/10.1016/j.virusres.2010.05.016