Nucleotide sequence of the 3'-terminal region of clover yellow mosaic virus RNA.

The nucleotide sequence of the 3'-terminal region of clover yellow mosaic virus RNA determined from cDNA clones contains one major open reading frame (ORF) encoding a protein with an Mr of 28,093 (28.1 K). A smaller ORF, in frame with the major one, is also present and encodes a 23.5K protein which is similar in size to the capsid protein of the virus and has several sequence similarities with the coat proteins of four other potexviruses. The smaller ORF is probably used for the expression of the coat protein because the capsid subgenomic mRNA probably does not include the AUG of the 28.1K protein. Comparison of the amino acid sequences of the coat proteins of five potexviruses revealed a large number of identical and conservative replacements of amino acid residues.