Cover image

Cover The basic helix-loop-helix transcription factor Olig3 promotes the specification of class A dorsal neurons in the developing spinal cord. Shown here are two immunofluorescence images of spinal cords from E12.5 mouse embryos heterozygous (left) or homozygous (right) for an Olig3^GILacZ allele in which the Olig3 coding sequence was replaced by a GFP-IRES-LacZ cassette. The sections were analyzed using antibodies directed against GFP (green) and the class A dI3 neuron subtype marker, Isl1 (red). The homozygous mutant shows the ectopic accumulation of GFP⁺ neurons to lateral positions in the dorsal spinal cord. (For details, see Mller et all., 733.)