Spatially and temporally regulated expression of N-acetylglucosamine-6-O-sulfotransferase during mouse embryogenesis.

GlcNAc-6-O-sulfotransferase is involved in formation of 6-sulfo-N -acetyllactosamine-containing structures such as 6-sulfo sialyl Lewis x. We investigated the mode of expression of GlcNAc-6-O-sulfotransferase during postimplantation embryogenesis in the mouse by in situ hybridization. Sulfotransferase mRNA was not detected on embryonic day (E) 6.5, while on E7.5 it was detected in the mesoderm, ectoderm, and ectoplacental cone. On E10.5, the sulfotransferase signals were mainly observed in the nervous tissue. On E12.5 and 13.5, various tissues in the process of differentiation expressed this mRNA. Several epithelial and mesenchymal tissues undergoing epithelial-mesenchymal interactions strongly expressed the mRNA. For example, in the developing tooth strong sulfotransferase mRNA expression was found only in the condensing mesenchyme on E13.5. On E13.5 and 15.5, the sites showing intense expression of the sulfotransferase again became restricted. In the brain, sulfotransferase mRNA was frequently found as discrete signals in narrow regions. These results suggest that 6-sulfo-N-acetyllactosamine structures have important roles in development. On E13.5 and 15.5, G152 (6-sulfo sialyl Lewis x antigen) was expressed in the neocortex, and AG223 (6-sulfo Lewis x antigen) in the thalamus and neocortex where the sulfotransferase signal was detected. However, in other organs, expression of these antigens did not correlate with the sulfotransferase mRNA, implicating complex nature of regulation of expression of the fucosyl 6-sulfo antigens.