title: The N-terminal region containing the zinc finger domain of tobacco streak virus coat protein is essential for the formation of virus-like particles.
abstract: Tobacco streak virus (TSV), a member of the genus Ilarvirus (family Bromoviridae), has a tripartite genome and forms quasi-isometric virions. All three viral capsids, encapsidating RNA 1, RNA 2 or RNA 3 and subgenomic RNA 4, are constituted of a single species of coat protein (CP). Formation of virus-like particles (VLPs) could be observed when the TSV CP gene was cloned and the recombinant CP (rCP) was expressed in E. coli. TSV VLPs were found to be stabilized by Zn(2+) ions and could be disassembled in the presence of 500 mM CaCl2. Mutational analysis corroborated previous studies that showed that an N-terminal arginine-rich motif was crucial for RNA binding; however, the results presented here demonstrate that the presence of RNA is not a prerequisite for assembly of TSV VLPs. Instead, the N-terminal region containing the zinc finger domain preceding the arginine-rich motif is essential for assembly of these VLPs.
authors.affiliation: Department of Biochemistry, Indian Institute of Science, Bangalore, 560 012, India.
authors.forename: Chhavi
authors.initials: C
authors.lastname: Mathur
authors.forename: Kalyani
authors.initials: K
authors.lastname: Mohan
authors.forename: T R
authors.initials: TR
authors.lastname: Usha Rani
authors.forename: M
authors.initials: M
authors.lastname: Krishna Reddy
authors.forename: Handanahal S
authors.initials: HS
authors.lastname: Savithri
mesh_terms: D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004252:DNA Mutational Analysis; D004926:Escherichia coli / Q000235:genetics; D019179:Ilarvirus / Q000502:physiology*; D054730:Protein Interaction Domains and Motifs; D055503:Protein Multimerization; D055550:Protein Stability; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D022701:Virosomes / Q000378:metabolism*; D015032:Zinc / Q000378:metabolism; D016335:Zinc Fingers
chemical_list: D036022:Capsid Proteins; D011994:Recombinant Proteins; D022701:Virosomes; D015032:Zinc