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 "Blaufränkisch". 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 "Blaufränkisch". 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.