Figure 3.

Osmotic Stress Arrests Cell Cycle and Subsequently Triggers Cell Cycle Exit.

(A) Ploidy analysis of leaf 3 dissected from plants transferred to control, mannitol-, or ACC-containing media at 9 DAS when the 3rd leaf is fully proliferating. Percentage of 2C, 4C, and 8C nuclei is presented. EI stands for endoreduplication index and represents the average number of endocycles undergone by a typical nucleus (EI = 1*4C+2*8C+3*16C). Data show means ± se from three independent experiments with multiple leaves pooled in each experiment.

(B) Leaf 3 of CYCB1;1:DBox-GUS plants 48 h (11 DAS) after transfer to control, mannitol-, or ACC-containing medium. Blue staining indicates mitotic activity. Orange dot indicates leaf tip. Bar = 0.5 mm.