Figure EV4. Interaction of Nrg3‐ and Nrg3ΔEGF‐expressing HEK293 cells with ErbB4⁺ neurons.

• A, B
  Neurons from Nrg3 mutant mice were co‐cultured with (A) Nrg3‐ and (B) Nrg3ΔEGF‐expressing HEK293 cells and immunostained for Nrg3/Nrg3ΔEGF (red) and ErbB4 (green). DAPI was used to counterstain nuclei (blue). Nrg3 and ErbB4 are highly enriched in contact areas between Nrg3‐expressing HEK cells and ErbB4⁺ interneurons (A); (A′ and A″) show lower exposures of the immunofluorescence signals of ErbB4 and Nrg3. Note that Nrg3ΔEGF and ErbB4 remained evenly distributed when an ErbB4⁺ interneuron was contacted by an Nrg3ΔEGF‐expressing HEK cell (B). Scale bar: 25 μm