FIGURE 4:

Effect of poly-Lys addition on the motility defect of ida6. (A) The motility defect in ida6 (DRC2-deficient) cells was partially rescued by the addition of hyper-poly-Lys on DRC4. No restoration of the flagellar motility was observed in tpg1ida6. Asterisks indicate statistically significant differences (p < 0.01). The p values were calculated using Student’s t test. Means ± SEM for the mean swimming velocities were calculated from 20 cells. See Supplemental Figure S3B for the swimming velocities of other strains. (B) Schematic diagrams of the cross-bridge between the hyper-poly-Lys peptide on DRC4 and the polyglutamate chain of the B-tubule. In ida6, the absence of DRC2 causes structural defects in the N-DRC and weakens its interaction with the B-tubule. The hyper-poly-Lys peptide on DRC4 reinforces the interaction with the polyglutamylated tubulins to partially restore N-DRC function.