Figure 6.

Two T-DNA Insertional Mutations Promote Plant Growth.

(A) Schematic representation of two T-DNA insertion sites in the TTL gene. ttl-1 contains the T-DNA insertion in the 117th codon of the second exon, whereas ttl-2 has the T-DNA inserted 15 bp upstream of the presumed ATG start codon.

(B) RNA gel blot analysis of the TTL gene expression in the two ttl mutants.

(C) Phenotypic comparison between the two ttl mutants and the corresponding wild-type plant (Ws-0) grown for 5 weeks under the 16-h-light/8-h-dark growth condition.

(D) Quantitative analysis of the hypocotyl growth of the ttl-1 mutants grown for 5 d in the dark or under a short-day (8-h-light/16-h-dark) growth condition. Hypocotyl growth is expressed as a percentage of the hypocotyl length of the 5-d-old wild-type seedlings grown in the dark, and each data point represents the average of ∼50 seedlings.

(E) Quantitative analysis of the height and petiole length of the ttl-1 mutants relative to those of the wild-type control plants. Both the wild-type control and the ttl-1 mutants were grown in soil for 7 weeks under the 16-h-light/8-h-dark growth condition. The length of the main inflorescence stem was used as the height of an adult plant, and the average petiole length of the three longest rosette leaves of each analyzed plant was taken as the petiole length. For (D) and (E), each data point represents the average of 16 plants, and the error bar denotes standard error.

(F) Shown are a 5-week-old ttl-1 mutant and a 5-week-old wild-type (Ws-0) plant.