Development of mouse hepatitis virus and SARS-CoV infectious cDNA constructs

Area of Science:

• Virology
• Molecular Biology
• Genomics

Background:

• Transmissible gastroenteritis virus (TGEV) and mouse hepatitis virus (MHV) are significant viral pathogens.
• Understanding coronavirus replication and pathogenesis is crucial for public health.

Purpose of the Study:

• To develop a novel strategy for assembling large viral RNA and DNA genomes.
• To create infectious recombinant viruses for studying viral functions.
• To establish a tool for rapid development of infectious clones for emerging coronaviruses like SARS-CoV.

Main Methods:

• A novel construction strategy using contiguous cDNA subclones for genome assembly.
• Generation of recombinant viruses with marker mutations.
• Engineering MHV to express foreign genes, such as green fluorescent protein (GFP).
• Application of the strategy to develop an infectious clone of SARS-CoV.

Main Results:

• Successfully generated infectious recombinant TGEV and MHV with efficient replication.
• Demonstrated the feasibility of inserting foreign genes into MHV.
• Developed an infectious clone of SARS-CoV within 2 months of its identification.

Conclusions:

• The novel assembly strategy is effective for creating large viral genomes and recombinant viruses.
• This approach provides a critical tool for studying coronavirus replication and pathogenesis.
• The availability of infectious cDNAs opens new avenues for coronavirus genetic research.