nphp-1 and nphp-4 mutants have misshaped, long, and stunted cilia. (A) CEM cilia are visualized using Ppkd-2∷tbb-4∷GFP. Dark gray indicates the frequency of misshaped curly CEM cilia; light gray indicates the frequency of stunted or mispositioned cilia. nphp-1 mutants have predominantly curly CEM cilia with some stunted cilia. nphp-4 and nphp-1;nphp-4 mutants have equal numbers of stunted and curly cilia. At least 50 animals are scored per genotype (∼200 individual CEM cilia are observed). Error bars indicate ±SEM. (B) CEM cilia were divided into wild-type, curly, and stunted categories. From z stack compressions of 3D wild-type and mutant CEM cilia; lengths were measured by tracing the cilium from the base of the TZ to the end of the axoneme. Curly cilia are significantly longer than the wild type. Stunted or misplaced cilia are slightly shorter than the wild type. The z distance of curls is not represented in this assay. p-values from a t test compare mutants to the wild type.