Lumen formation in collagen I precedes ciliogenesis.

<p>Wild type MDCK cells were grown in collagen I and stained for Hoechst, Actin and acetylated Tubulin at indicated time points. Merged section from one z-plane (left), projection of acetylated Tubulin from entire z-stack (right). At 24–48 h lumina are forming but no cilia are present. Cilia start appearing at day 4. At 10 days fully polarized lumina and cilia are present. Scale Bars: 10 µm.