Fig. 3

5-HT6 mutations regulated ciliary length, cilia branching number, and percentage of neurons with branched cilia. (a) D72A, D106A, and F69L + T70I + D72A mutations influenced ciliary length. These mutations of 5-HT6 restored primary ciliary length increased by overexpression of 5-HT6. 5-HT6 (green) indicated primary cilia. (b) D72A, D106A, and F69L + T70I + D72A mutations restored normal cilia length. EGFP, ***p < 0.001; D72A, **p < 0.01; D106A, **p < 0.01; F69L + T70I + D72A, ***p < 0.001 (Kruskal–Wallis test, p < 0.001). (c) D72A, D106A, and F69L + T70I + D72A mutations influenced the number of ciliary branches. These mutations of 5-HT6 significantly reduced the number of ciliary branches. EGFP, **p < 0.01; D72A, **p < 0.01; D106A, **p < 0.01; F69L + T70I + D72A, **p < 0.01 (Kruskal–Wallis test, p < 0.001). (d) F69L, T70I, D72A, D106A, F284A, A230F + Q234F, and F69L + T70I + D72A mutations decreased the percentage of branched cilia. EGFP, ***p < 0.001; F69L, **p < 0.01; T70I, *p < 0.05; D72A, ***p < 0.001; D106A, ***p < 0.001; F284A, **p < 0.01; A230F + Q234F, *p < 0.05; F69L + T70I + D72A, ***p < 0.001 (Kruskal–Wallis test, p < 0.001). All groups were compared with the 5-HT6 group, which was transfected with 5-HT6-GFP. Scale bars, 10 μm. All data presented as mean ± SEM (≥3 independent experiments). 5-HT6, serotonin 6 receptor, DAPI 4',6-diamidino-2-phenylindole, EGFP enhanced green fluorescent protein