Embryos were fixed by transcardiac perfusion with freshly-prepared
4% paraformaldehyde (Sigma). Brains were dissected, and 100 mm sections were prepared using a Leica
VT1000S vibrosector. Slices were transferred into PBS with 0.5 μg/mL
sodium azide (Sigma), then blocked with PBS supplemented with 3%
horse serum (Invitrogen) and 0.3%
Triton X-100 (Sigma) during 1 h, and incubated overnight at 4°C with the following primary antibodies:
chicken GFP (Abcam, 1:2,000), rabbit Pax6 (Covance, 1:1000), Sox2 (Santa Cruz Biotechnology, 1:500),
PCNA (Millipore, 1:200),
phospho-Histone H3 (Abcam, 1:100), Tbr2 (Abcam, 1:500),
Neurod2 (Abcam, 1:500), or mouse β3-tubulin (Tuj1 epitope, Covance, 1:1000). After three washes with PBS/0.1%
Triton X-100, slices were incubated in PBS for 1 h at room temperature and incubated 2 h at room temperature with the appropriated
Alexa 488 (1:1,000, Molecular Probes),
Cyanine 3 or
Cyanine 5 (1:400, Jackson ImmunoResearch) secondary antibodies. Sections were again washed three times with PBS/0.1%
Triton X-100, stained with
Hoechst (bisBenzimide H 33258, Sigma) for 5 min and washed twice in PBS. The sections were next mounted on a
Superfrost slide (Thermo Scientific) and dried using a brush before adding
Glycergel mounting medium (Dako). Imaging was performed using a
Zeiss LSM780 confocal microscope controlled by the
Zen Black software (Zeiss).
Bonnefont J., Tiberi L., van den Ameele J., Potier D., Gaber Z.B., Lin X., Bilheu A., Herpoel A., Velez Bravo F.D., Guillemot F., Aerts S, & Vanderhaeghen P. (2019). Cortical Neurogenesis Requires Bcl6-Mediated Transcriptional Repression of Multiple Self-Renewal-Promoting Extrinsic Pathways. Neuron, 103(6), 1096-1108.e4.