Characterization of the protease domain of Rice tungro bacilliform virus responsible for the processing of the capsid protein from the polyprotein
| Autor: | Philippe Marmey, Ana Rojas-Mendoza, Claude M. Fauquet, Alexandre de Kochko, Roger N. Beachy |
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| Rok vydání: | 2005 |
| Předmět: |
Gene Expression Regulation
Viral Models Molecular Proteases ENZYME STRUCTURE PROTEASE Protein Conformation medicine.medical_treatment Molecular Sequence Data Gene Expression Regulation Enzymologic lcsh:Infectious and parasitic diseases MALADIE DES PLANTES MODELE Virology PROTEINE medicine lcsh:RC109-216 Amino Acid Sequence Movement protein Badnavirus MUTATION Rice tungro bacilliform virus EXPERIMENTATION IN VITRO Protease biology CHROMATOGRAPHIE EN PHASE LIQUIDE Research PHYTOVIRUS POLYPROTEINE P3 BIOLOGIE MOLECULAIRE SPECTROMETRIE biology.organism_classification Molecular biology Reverse transcriptase Open reading frame Infectious Diseases Capsid Capsid Proteins ANALYSE GENETIQUE RIZ Peptide Hydrolases |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname Virology Journal, Vol 2, Iss 1, p 33 (2005) Virology Journal |
| Popis: | [Background] Rice tungro bacilliform virus (RTBV) is a pararetrovirus, and a member of the family Caulimoviridae in the genus Badnavirus. RTBV has a long open reading frame that encodes a large polyprotein (P3). Pararetroviruses show similarities with retroviruses in molecular organization and replication. P3 contains a putative movement protein (MP), the capsid protein (CP), the aspartate protease (PR) and the reverse transcriptase (RT) with a ribonuclease H activity. PR is a member of the cluster of retroviral proteases and serves to proteolytically process P3. Previous work established the N- and C-terminal amino acid sequences of CP and RT, processing of RT by PR, and estimated the molecular mass of PR by western blot assays. [Results] A molecular mass of a protein that was associated with virions was determined by in-line HPLC electrospray ionization mass spectral analysis. Comparison with retroviral proteases amino acid sequences allowed the characterization of a putative protease domain in this protein. Structural modelling revealed strong resemblance with retroviral proteases, with overall folds surrounding the active site being well conserved. Expression in E. coli of putative domain was affected by the presence or absence of the active site in the construct. Analysis of processing of CP by PR, using pulse chase labelling experiments, demonstrated that the 37 kDa capsid protein was dependent on the presence of the protease in the constructs. [Conclusion] The findings suggest the characterization of the RTBV protease domain. Sequence analysis, structural modelling, in vitro expression studies are evidence to consider the putative domain as being the protease domain. Analysis of expression of different peptides corresponding to various domains of P3 suggests a processing of CP by PR. This work clarifies the organization of the RTBV polyprotein, and its processing by the RTBV protease. |
| Databáze: | OpenAIRE |
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