Figure 6.  Diagram of the Tobacco mosaic virus (TMV) genome.

The TMV genome is a messenger-sense RNA that produces 4 proteins during virus infection. The RNA possesses a cap structure at the 5’-end and a tRNA-like structure charged with the amino acid histidine (His) at the 3’-end. Two RNA polymerase proteins are produced. One protein possesses methyltransferase (MET, capping enzyme) and RNA helicase (HEL) domains. Another protein is produced due to ribosomes bypassing a leaky stop codon UAG; in addition to MET and HEL, it contains an RNA-dependent RNA polymerase (RdRp) domain. Two other proteins, movement protein (MP) and capsid protein (CP), are produced from the viral RNA (Courtesy V. Dolja).