Molecular characterization of grapevine plants transformed with GFLV resistance genes: I

The Grapevine FanLeaf Virus-Coat Protein ( GFLV CP) gene was inserted through Agrobacterium-mediated transformation in Vitis vinifera 'Nebbiolo', 'Lumassina' and 'Blaufrankisch'. Two plasmids were used: pGA-CP+ (full-length GFLV CP gene with an introduced start codon) and pGA-AS ( same gene in antisense orientation). Forty-three transgenic lines were regenerated. As several lines in Southern blots share same hybridization patterns, eight independent line groups resulted for 'Nebbiolo', one for 'Lumassina', and two for 'Blaufrankisch'. Inserted T-DNA copies ranged from one to three; one line probably contains an incomplete copy of T-DNA. Except for one 'Nebbiolo' line, no evidence for methylation of the transgene at cytosine residues was found by Southern analyses. Specific mRNA was present at variable expression levels; some lines accumulated the coat protein while in others the protein was not detectable by ELISA.