Figure 6.

Starch-Excess Phenotype in ATG6-Silenced Nicotiana benthamiana.

(A) Iodine staining of leaves from ATG6-silenced and nonsilenced plants. Leaves were harvested at the end of the night for detection of starch content. Starch was almost exhausted in control leaves but was readily detected in the ATG6-silenced leaves. These results were reproduced in 10 independent experiments using two to three leaves in each experiment. Representative results are presented.

(B) Quantification of leaf starch content in ATG6-silenced and nonsilenced plants. Values are means ± se from three replicate leaf samples. Two asterisks indicate a significant difference (P < 0.01; Student’s t test).

(C) Ultrastructural analysis of starch accumulation in mesophyll cells. At the end of the night, almost no starch granules were visible in the chloroplasts of control leaves, whereas starch granules were still present in the chloroplasts (arrowheads) of ATG6-silenced leaves. Cp, chloroplast; CW, cell wall; M, mitochondrion; S, starch; V, vacuole. Bars = 5 μm.

[See online article for color version of this figure.]