Primary cilia are altered in <i>Spag17</i>-deficient osteoblast, chondrocyte and MEFs cells.

<p>Cells were stained with anti-acetylated α-tubulin to visualize primary cilia and DAPI as a nuclei marker. (A) Primary cilia length from osteoblast cells. Scale bars, 5 μm. (B) Percentage of osteoblast cells expressing primary cilia. Scale bars, 20 μm (C) Primary cilia length from chondrocyte cells. Scale bars, 5 μm. (D) Percentage of chondrocyte cells expressing primary cilia. Scale bars, 20 μm. Mouse embryonic fibroblasts (MEFs) were isolated from embryos at E12.5. (E) Detection of <i>Spag17</i> mRNA and protein in MEFs. RT-PCR products were generated by primers from exon 4 and 5. The knockout mice have a deletion of the entire exon 5. Detection of SPAG17 protein by western blot using an antibody against C-terminal domain. (F) After serum-starvation to promote cilia growth, primary cilia were visualized in the MEFs with acetylated tubulin antibody, and DAPI as a nuclei marker. Primary cilia from <i>Spag17</i>-mutant MEFs were significantly shorter than wild-type. Scale bars, 5 μm. (G) <i>Spag17</i> knockdown in WT MEFs cells after treatment with <i>Spag17</i> siRNA duplex reproduced the shorter primary cilia phenotype. Scale bars, 5 μm. Arrows indicate primary cilia. (+/+), wild-type, (-/-); <i>Spag17</i>-mutant mice. Data are presented as means ± SEM. * Indicates statistically significant differences, p< 0.05.