EDAR and infection: Although Dl-GFP+—Dl-GFP+ pairs formed during infection can arise either from single Dl-GFP+ cells or from Dl-GFP+—Notch+ progenitor pairs, these results support a symmetric expansion of the Dl+ cell pool followed by diverting a subset of them to be committed into EB and quickly differentiated, likely due to the presence of the extended cell-cell contact (Fig 2L).