Dataset Information

Self-interaction of the cucumber mosaic virus 2b protein plays a vital role in the suppression of RNA silencing and the induction of viral symptoms.

ABSTRACT: The cucumber mosaic virus (CMV) 2b protein is an RNA silencing suppressor protein that can also play direct and indirect roles in symptom induction. Previous work has shown that a hybrid virus, FRad35(2b) -CMV (renamed here as CMV-FRad2b-Pro), generated by replacement of the 2b gene of strain Fny-CMV with that from Rad35-CMV, displays markedly lower pathogenicity than Fny-CMV on Nicotiana species. However, the replacement of proline with leucine at position 55 of the 2b protein of CMV-FRad2b-Pro (protein Rad2b-Pro) created a virus (CMV-FRad2b-Leu) that induced severe symptoms. Infection of Arabidopsis thaliana mutants defective in the expression of DICER-like (DCL) endoribonucleases 2 and 4, which mediate antiviral RNA silencing, as well as of dcl3 and dcl2/3/4 triple-mutant plants, indicated that Rad2b-Pro was a weaker RNA silencing suppressor than the protein Rad2b-Leu. This was confirmed in Nicotiana benthamiana using agroinfiltration assays, showing that, compared with either Rad2b-Leu or the Fny2b protein, Rad2b-Pro was ineffective at inhibiting local or systemic silencing of expression of a green fluorescent protein reporter gene. Transgenic expression of Rad2b-Leu, but not of Rad2b-Pro, in Arabidopsis induced symptom-like phenotypes and rescued the accumulation of the 2b-deletion mutant Fny-CMV?2b. Bimolecular fluorescent complementation indicated that, in?planta, Rad2b-Leu, but not Rad2b-Pro, self-interacts. Thus, self-interaction is crucial to the ability of the 2b protein to suppress silencing and induce a symptom-like phenotype, and is dependent on the properties of the residue at position 55.

SUBMITTER: Xu A

PROVIDER: S-EPMC6638684 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Self-interaction of the cucumber mosaic virus 2b protein plays a vital role in the suppression of RNA silencing and the induction of viral symptoms.

Xu Aixia A Zhao Zhijing Z Chen Wenhu W Zhang Hengmu H Liao Qiansheng Q Chen Jishuang J Carr John P JP Du Zhiyou Z

Molecular plant pathology 20130619 8

The cucumber mosaic virus (CMV) 2b protein is an RNA silencing suppressor protein that can also play direct and indirect roles in symptom induction. Previous work has shown that a hybrid virus, FRad35(2b) -CMV (renamed here as CMV-FRad2b-Pro), generated by replacement of the 2b gene of strain Fny-CMV with that from Rad35-CMV, displays markedly lower pathogenicity than Fny-CMV on Nicotiana species. However, the replacement of proline with leucine at position 55 of the 2b protein of CMV-FRad2b-Pro ...[more]

PMID: 23782515

Similar Datasets

Project description:Taxonomic relationshipsCucumber mosaic virus (CMV) is the type species of the genus Cucumovirus in the family Bromoviridae, which also encompasses the Peanut stunt virus (PSV) and the Tomato aspermy virus (TAV). Nucleotide sequence similarity among these three cucumoviruses is 60%-65%. CMV strains are divided into three subgroups, IA, IB and II, based on the sequence of the 5' untranslated region of the genomic RNA 3. Overall nucleotide sequence similarity among CMV strains is approximately 70%-98%. GEOGRAPHICAL DISTRIBUTION, HOST RANGE AND SYMPTOMATOLOGY: CMV is distributed worldwide, primarily in temperate to tropical climate zones. CMV infects more than 1200 species of 100 plant families, including monocot and dicot plants. Symptoms caused by CMV infection vary with the host species and/or CMV strain, and include mosaic, stunt, chlorosis, dwarfing, leaf malformation and systemic necrosis. CMV disease is spread primarily by aphid transmission in a nonpersistent manner.Physical propertiesIn tobacco sap, the thermal inactivation point of the viral infectivity is approximately 70 °C (10 min), the dilution end-point is approximately 10(-4) and viral infectivity is lost after a few days of exposure to 20 °C. Viral infectivity can be retained in freeze-dried tissues and in the form of virions purified using 5 mm sodium borate, 0.5 mm ethylenediaminetetraacetic acid and 50% glycerol (pH 9.0) at -20 °C. CMV particles are isometric, approximately 28-30 nm in diameter and are composed of 180 capsid subunits arranged in pentamer-hexamer clusters with T= 3 symmetry. The sedimentation coefficient (s(20) ,(w) ) is c. 98 S and the particle weight is (5.8-6.7) × 10(6) Da. The virions contain 18% RNA. The RNA-protein interactions that stabilize the CMV virions are readily disrupted by sodium dodecylsulphate or neutral chloride salts. GENOMIC PROPERTIES: The genomic RNAs are single-stranded messenger sense RNAs with 5' cap and 3' tRNA-like structures containing at least five open reading frames. The viral RNA consists of three genomic RNAs, RNA 1 (c. 3.3 kb), RNA 2 (c. 3.0 kb) and RNA 3 (c. 2.2 kb), and two subgenomic RNAs, RNA 4 (c. 1.0 kb) and RNA 4A (c. 0.7 kb). The 3' untranslated regions are conserved across all viral RNAs. CMV is often accompanied by satellite, noncoding, small, linear RNA that is nonhomologous to the helper CMV.

Dataset Information

Self-interaction of the cucumber mosaic virus 2b protein plays a vital role in the suppression of RNA silencing and the induction of viral symptoms.

Publications

Self-interaction of the cucumber mosaic virus 2b protein plays a vital role in the suppression of RNA silencing and the induction of viral symptoms.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets