Molecular Advances in Severe Acute Respiratory Syndrome-associated Coronavirus (SARS-CoV)

Chow, Ken Yan Ching; Hon, Chung Chau; Hui, Raymond Kin Hi; Wong, Raymond Tsz Yeung; Yip, Chi Wai; Zeng, Fanya; Leung, Frederick Chi Ching

The reverse genetics system, a very useful tool in studying function of viral proteins and its mutations, was firstly described by Master's group (82 ) for MHV in Coronaviridae. In less than six months since the first identification of the SARS-CoV (2 ), Yount et al (83 ) developed the reverse genetic systems for this coronavirus using the full-length cDNA clone of Urbani strain, by combining six component clones spanning through the entire genome. Following in vitro transcription and the transfection of the resulting RNA transcripts, a rescued recombinant virus was found to be capable of replication in the same way as the wild type. Expected marker mutations introduced were also identified. The success of the experiment offers hope for the development of attenuated strains of live vaccine against the SARS-CoV (9 ).