Visualizing fluorescently tagged proteins in live cells of the neural tube with confocal microscopy. (A, B) Low dose tamoxifen induces expression of DsRed at E8.5 in single cells within the embryo and neuroepithelium. (C, D) Cilia are marked by GFP in E8.5 embryo infected with SsTR3-GFP lentivirus. White arrowheads mark GFP expressed in cilia. (E) Sagittal view and (F) dorsal view of E8.5 embryo carrying Olig2-GFP shows GFP expression within neuroepithelium. Bar is 30 μm (A, B, C and F), 15 μm (D) and 1.5 μm (E).