Organization and interviral homologies of the coat protein gene of white clover mosaic virus.

The sequence of 1612 nucleotides of the 3'-terminal region of white clover mosaic virus (WCIMV) has been determined from cDNA clones. The viral sense RNA contains four open reading frames of Mr 20,684, Mr 7219, Mr 12,989, and at least Mr 17,000. The latter begins 5' to the sequence determined. The amino acid sequence of the open reading frame encoding the 20,684 polypeptide shows marked homology to the coat proteins of three other potexviruses. The putative coat protein gene was subcloned in a T7 transcription plasmid and RNAs produced by in vitro transcription were translated in the rabbit reticulocyte lysate system. The polypeptide products comigrated on SDS-polyacrylamide gels with one of those synthesized by the in vitro translation of viral RNA, and were immunoprecipitable with antiserum raised against WCIMV, confirming the location of the coat protein gene.