The Nucleotide Sequence of Satellite RNA in Grapevine Fanleaf Virus,

The nucleotide sequence of cDNA copies of grapevine fanleaf virus (strain F13) satellite RNA has been determined. The primary structure obtained was 1114 nucleotides in length, excluding the poly(A) tail, and contained only one long open reading frame encoding a341 residue, highly hydrophilic polypeptide of Mr 37 275. The coding sequence was bordered by a leader of 14 nucleotides and a 3'-terminal non-coding region of 74 nucleotides. No homology has been found with small satellite RNAs associated with other nepoviruses. Two limited homologies of eight nucleotides have been detected between the satellite RNA in grapevine fanleaf virus and those in tomato black ring virus, and a consensus sequence U. G/UGAAAAU/AU/AU/A at the 5 ' end of nepovirus RNAs is reported. A less extended consensus exists in this region in comovirus and picornavirus RNA. Grapevine fanleaf nepovirus (GFLV) is responsible for one of the most widespread and damaging viral diseases of grapevine. The isometric particles of about 28 nm in diameter are morphologically and serologically indistinguishable. They sediment as three components in sucrose gradients (Quacquarelli et al., 1976). GFLV has a bipartite RNA genome separatel