A tool to disrupt polyploidization. (A) Cartoon depicting C. elegans intestinal development, the origins of polyploidy in this tissue, and the cell numbers and ploidy values at each developmental stage. (B) Cartoon depicting timing of intestine-specific CDK-2 degradation and timing of CDK-2 activity in wild-type and CDK-2^gut(−) intestines. (C) Cartoon depicting genetics of experimental and control strains. (D) Quantification of intestinal nucleus number in L1 worms, representing final cell number. (E) Quantification of intestinal nucleus number in L4 worms, representing final nucleus number. (F) Sum projections of 3D images of day 1 adult worms fixed and stained with Hoechst DNA-binding dye (viridis-inferno coloring). Insets show nuclei from the third intestinal ring and neighboring pachytene germline cells. (G) Quantification of nucleus ploidy in control and CDK-2^gut(−) F1 and F2 day 1 adult intestines. Dots and error bars represent means and 95% confidence interval. Kruskal–Wallis test P = 6.6 × 10⁻⁸⁵; P values shown are from post-hoc Dunn test with Benjamini-Hochberg multiple hypothesis testing correction. (H) Representative DIC images of live adult control and CDK- 2^gut(−) worms. Intestines are outlined in blue (control) or red (CDK-2^gut(−)) dotted lines. Worms are age-matched at 96 h post-egg lay. (I) Quantification of intestine volume, estimated from length and cross-sectional area. Each point represents one worm. In D, E, and I, bars and error bars represent means and 95% confidence intervals; P values are from Mann–Whitney U tests. (J) Left: Estimation of DNA/cytoplasm ratio in control and CDK-2^gut(−) intestines from parameters in D–I. Error bars represent combined standard deviation. Right: Cartoon depicting normal and DNA-dilute cells.