Fig. 3

CrCYB5D1 is responsible for controlling cis–trans flagellar dominance. Real-time images and schematic diagrams of the flagellar beat waveforms in IP (HS211 or Crcyb5d1) (A), Slip (Crcyb5d1) (B), and AP (Crcyb5d1) (C) states: IP, in-phase; Slip, phase slip; AP, antiphase. The schematic diagrams at right show the principle for comparing the waveforms of cis- and trans-flagella using the rotating angle of the cell body. The green line was set between the base of the two flagella, bisects the cell body, and changed over time. The red line is perpendicular to the green line at 0.000 s and was fixed during the analysis. The angle (θ) between the red and green lines was used to monitor the rotation of the cell body and was 90° at 0.000 s. Images were taken at 500 frames per second using a high-speed video microscopy. The time of each image is indicated. (Scale bars, 5 μm.) (D) Typical sequential flagellar bending patterns in a single beat cycle were reconstructed from the waveforms in A, B, and C. (E) Dot graph showing the ratio of bend envelope area between the trans- and cis-flagellum. All values are shown as the mean ± SD. (F) Comparing the angle (θ) of each beating waveform over time in HS211 and Crcybd51: IP, Box-marked line; AP, Triangle-marked line; Slip, Round-marked line. (G) Comparison of the percentage of IP, Slip, and AP states in beat cycles of HS211 and Crcyb5d1. The number of cycles is indicated. (H) Percentage of coordinated beat cycles in the indicated strains. All values are shown as the mean ± SEM of three independent experiments. ***P < 0.001. (I) The effect of Ca²⁺ concentration on the dominance of cis- and trans-axonemes in HS211 and Crcybd51. Each point shows the average and the SD from three experiments. The number of cells counted in each experiment was larger than 150.