Construction and characterization of an infectious molecular clone of maedi-visna virus that expresses green fluorescent protein

The construction of a molecular clone of maedi-visna virus (MVV) expressing the enhanced green fluorescent protein (EGFP) is described. The egfp gene was inserted into the gene for dUTPase since it has been shown that dUTPase is dispensable for MVV replication both in vitro and in vivo. MVV-egfp is infectious and EGFP expression is stable over at least six passages. This fluorescent virus will be a useful tool for monitoring MVV infections.