Fig. 7.

The cep3-1 mutant sustains mitotic activity for longer under C and N limitation, and CEP3 peptide impedes the recovery of mitotic cells into S-phase. (A) Time course showing the percentage of roots with EdU-florescent cells relative to levels in day four samples. Plants were grown in modified N-free liquid medium with suboptimal light to prevent photoautotrophic growth. (B) Percentage of roots with EdU-positive cells after 24 h of incubation with 1 mM Glc. n≥10 roots. Letters indicate statistically significant differences within each time point (P<0.05, ANOVA with Bonferroni multiple comparison; Genstat). (C) After growth under N and C limitation, CEP3 peptide treatment reduces the number of root meristem cells in the S-phase of the cell cycle within 12 h. Plants were grown in modified N-free liquid medium under suboptimal light for 6 d to synchronize meristematic cells. Glc or CEP3+Glc was added at time 0 (after synchronization) and plants were assayed at the specified times. ***P<0.001 (t-test, compared with no peptide control). n=8 roots per time point.