Figure 2.

Sas4 is required for BB assembly. (A) WT and sas4Δ cells at 0, 6, 12, and 24 h post-knockout in cycling cells at 30°C (BB, centrin, grayscale). (B) Quantification of BB frequency in a 10-µm distance within the medial region of ciliary rows, based on centrin staining shown in A. Analysis was performed in triplicate on five ciliary rows per cell for 20 cells per condition (total of 300 rows per cell line per time point). P value for 0 h post-knockout between WT and sas4Δ is not significant. Error bars denote SEMs. (C) sas4Δ rescue by reintroduction of SAS4 gene. Image is representative of two independent experiments. (D) WT and sas4Δ cells (BB, centrin, grayscale) maintained in G1 arrest at 30°C for 24 h post-knockout. (E) Model of sas4Δ phenotypes. BBs are lost when cells progress through the cell cycle but are not lost if maintained in G1 arrest. Scale bars, 5 µm.