Immunohistochemistry and imaging

Immunohistochemistry was as previously described (Young et al, 2014) using Chicken anti‐GFP (1:500, Aves) and goat anti‐DCX (1:100, Santa Cruz) primary and Alexafluor‐conjugated (Invitrogen) secondary antibodies. TUNEL method was performed using the In situ cell death detection kit, TMR red (Roche‐12156792910) to detect apoptosis. Sections were imaged with Zeiss 710 Laser Scanning Microscopy. For co‐localisation in GFP⁺ cells, a 20× or 40× oil immersion objective was used and Z stacks were generated at 2‐μm intervals. Confocal images were analysed with ImageJ.