Figure 6.

Overexpression of CHLSYN triggers sense suppression and alters chlorophyll and tocopherol concentrations in leaves. A, Plants shown are Col-0 and Col-0 expressing chlorophyll synthase under control of the CaMV35S promoter at 5 d, 5 weeks, and 7 weeks of age and maintained in a 14 h of light/10 h of dark cycle. Semiquantitative RT-PCR analysis of expression of chlorophyll synthase in leaves from these plants is shown in A, middle. The wild type (Wt) and Wt/SYN-3, Wt/SYN-7, Wt/SYN-8, and Wt/SYN-13 are representative of plants of Col-0 and four independent transgenic chlorophyll synthase overexpression lines, respectively. The gene encoding UBC (At5g25670) was used as an internal control in RT-PCR analysis. Shown are chlorophyll (B) and tocopherol (C) concentrations of leaves from Wt plants and plants engineered for chlorophyll synthase overexpression from sampling of 5- and 7-week-old plants. Data represent means ± se of three independent biological replicates. *, P < 0.05; **, P < 0.01 (Student’s t test).