Addition of exogenous polypeptides on the mammalian reovirus outer capsid using reverse genetics

摘要

Addition of exogenous peptide sequences on viral capsids is a powerful approach to study theprocess of viral infection or to retarget viruses toward defined cell types. Until recently, it wasnot possible to manipulate the genome of mammalian reovirus and this was an obstacle to theaddition of exogenous sequence tags onto the capsid of a replicating virus. This obstacle hasnow been overcome by the advent of the plasmid-based reverse genetics system. In the present study, reverse genetics was used to introduce different exogenous peptides, up to 40amino acids long, at the carboxyl-terminal end of the σ1 outer capsid protein. The taggedviruses obtained were infectious, produce plaques of similar size, and could be easilypropagated at hight titers. However, attempts to introduce a 750 nucleotides-long sequencefailed, even when it was added after the stop codon, suggesting a possible size limitation atthe nucleic acid level.