title: Multiple targets for suppression of RNA interference by tomato aspermy virus protein 2B.
abstract: Viral suppressors of RNA interference (RNAi) appear to have evolved as a response to this innate genomic defense. We report the nucleic acid binding properties of the Cucumovirus RNAi suppressor tomato aspermy virus protein 2B (TAV 2B). Using total internal reflection fluorescence spectroscopy (TIRFS), we show that TAV 2B binds double-stranded RNA corresponding to siRNAs and miRNAs, as well as single-stranded RNA oligonucleotides. A number of positively charged residues between amino acids 20 and 30 are critical for RNA binding. Binding to RNA oligomerizes and induces a conformational change in TAV 2B, causing it to form a primarily helical structure and a 4:2 protein-RNA complex.
authors.affiliation: Institute of Biophysical Chemistry, Institute of Physical and Theoretical Chemistry, and Institute of Biochemistry, Goethe University Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany.
authors.forename: Umar Jan
authors.initials: UJ
authors.lastname: Rashid
authors.forename: Jan
authors.initials: J
authors.lastname: Hoffmann
authors.forename: Bernhard
authors.initials: B
authors.lastname: Brutschy
authors.forename: Jacob
authors.initials: J
authors.lastname: Piehler
authors.forename: Julian C-H
authors.initials: JC
authors.lastname: Chen
mesh_terms: D017799:Cucumovirus / Q000235:genetics / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000821:virology*; D009843:Oligoribonucleotides / Q000235:genetics / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D011485:Protein Binding; D034622:RNA Interference / Q000502:physiology*; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D009843:Oligoribonucleotides; D010446:Peptide Fragments; D012367:RNA, Viral; D014764:Viral Proteins