Ngn1 is a basic helix-loop-helix (bHLH) transcription factor expressed in specific regions within the developing brain and spinal cord, sensory ganglia, and olfactory epithelium. We have identified sequences both 5′ and 3′ of the mouse
ngn1 gene that function in regulating
ngn1 expression, and each of these sequences contains distinct regulatory cassettes for different subregions of the expression domain. Enhancers for expression in
ngn1 domains of the midbrain, hindbrain, trigeminal ganglia, and ventral–neural tube appear redundant and are spread both 5′ and 3′ of the
ngn1 coding sequence. In contrast, a single discrete dorsal–neural tube enhancer was located in the 5′ sequence that is conserved among mouse, human, chick, and zebrafish
ngn1 genes. Functionally, this enhancer is both necessary and sufficient for driving expression of a heterologous reporter in transgenic mice specifically to the dorsal domain of
ngn1 expression in the spinal neural tube. Thus, sequences are identified that can be used to direct temporally and spatially restricted expression of heterologous genes to the developing neural tube.