Complete nucleotide sequence of a South African isolate of Grapevine fanleaf virus

Abstract

The complete sequences of RNA1 and RNA2 have been determined for a South African isolate of Grapevine fanleaf virus (GFLV-SAPCS3). The two RNAs are, respectively, 7,342 and 3,817 nucleotides in length, excluding the poly(A) tails. RNA1 has a large open reading frame (ORF) of 6,852 nucleotides and a 5'-UTR and a 3'-UTR of 243 and 244 nucleotides, respectively. RNA2 encodes for an ORF of 3,330 nucleotides and has the highest nucleotide identity (90.4 %) with GFLV-F13. The full length nucleotide sequence of GFLV-SAPCS3 RNA1 had the highest nucleotide identity (86.5 %) to the French isolate GFLV-F13. The 5'- and 3'-UTRs of GFLV-SAPCS3 RNA2 are 272 nucleotides and 212 nucleotides (nt) in length, respectively. The GFLV-SAPCS3 RNA2 5'-UTR is 32-53 nt longer compared to other GFLV isolates. The GFLV-SAPCS3 RNA2 5'-UTR is also more closely related to GFLV-GHu and Arabis mosaic virus (ArMV) isolates than to other GFLV isolates. Putative intra- and interspecies recombination events between GFLV and ArMV isolates involving GFLV-SAPCS3 RNA1 and RNA2 were investigated. Recombination analysis software has indicated that the GFLV-SAPCS3 5'-UTR might have evolved from a recombinational event between GFLV-F13-type and ArMV-Ta-type isolate.