Rpgrip1l deficiency affects ciliary length. (A and B) MEFs were isolated from E12.5 WT and Rpgrip1l^−/− embryos. (A) Comparison of WT and Rpgrip1l^−/− ciliary length. Embryonic organs were separated from E12.5 embryos. At least 20 cilia per embryo were analyzed. n values (n refers to the number of embryos) are as follows: MEFs: WT, n = 4; Rpgrip1l^−/−, n = 5; limbs: WT, n = 4; Rpgrip1l^−/−, n = 5; hearts: WT, n = 4; Rpgrip1l^−/−, n = 5; lungs: WT, n = 4; Rpgrip1l^−/−, n = 4; livers: WT, n = 4; Rpgrip1l^−/−, n = 4. Error bars show standard error of the mean. (B) Elongation of E12.5 Rpgrip1l^−/− limb cilia are confirmed in comparison to fluorescence based cilia length measurement (10 cilia; SEM: 2.88 ± 0.14 µm; immunofluorescence: 2.44 ± 0.265 µm). Magnifications (termed as 1 and 2) show two examples of Rpgrip1l^−/− limb cilia. Bars: (overview) 10 µm; (magnification) 1 µm. (C) Absolute values of the quantified ciliary length of WT (n = 4 embryos) and Rpgrip1l^−/− (n = 5 embryos) limbs at E12.5 based on immunofluorescence. Rpgrip1l-negative cilia (2.44 ± 0.265 µm [standard error of the mean]) are significantly longer than WT cilia (1.25 µm ± 0.05 µm [standard error of the mean]). *, P < 0.05; **, P < 0.01; ***, P < 0.001.