We report here the expression pattern of Nkx3.1, a murine homolog of Drosophila bagpipe, in different stages of embryos and in neonates. Nkx3.1 was expressed in paraxial mesoderm at day 7.5 p.c., in the somite by day 8.0 p.c. and in a subset of vascular smooth muscle cells by day 9.5 p.c. In later stage embryos and neonates, Nkx3.1 was expressed in subpopulations of epithelial cells, particularly in epithelial outgrowths. Nkx3.1 was also expressed in restricted regions of the central nervous system.