Figure 4: Cloning of VEG1.

(a) In M. truncatula, MtFULc is located 17 Kb from MtSEP1, whose pea homologue maps to the VEG1 locus and is deleted in the veg1 mutant. (b) Lesions in the psfulc mutant alleles described in this work. Left, Southern blot on DNA of plants from a F2 population segregating for veg1, hybridized with a PsFULc probe. The same DNA samples were digested with BamHI and with EcoRI. Hybridization was observed with DNA from plants with a wild-type phenotype (2, 4, 6 and 7) but not from homozygous veg1 plants (3 and 5), showing that PsFULc is deleted in veg1. Right, mutations in the psfulc-2 and psfulc-3 alleles. The nucleotide changes in the mutant sequences are indicated in red. The G-to-A mutation in fulc-2 destroyed the splice donor site of exon 3. The C-to-T mutation in psfulc-3 caused a Q102STOP change. (c,d) Phenotype of the psfulc-2 and psfulc-3 mutant plants. Both plants show a non-flowering veg1 phenotype, where secondary inflorescences (I₂) are replaced by vegetative branches. (e) veg1-like phenotype of a PsFULc-VIGS plant. In the PsFULc-silenced plant, the I₂s appear in later nodes than in the control plant, and branches (arrowheads) develop in the nodes where I₂s (arrowheads) appear in the control plant.