Developmental regulation of diacylglycerol kinase ξ

We isolated cDNA clones of mouse diacylglycerol kinase ξ (DGKCξ) using a human DGKCξ probe by low-stringency hybridization. Mouse DGKCξ shares 88% identity at the nucleic acid level and 95% identity at the amino acid level with human DGKCξ. The DGKCξ protein was readily detectable in E12.5 mouse embryos. Its protein level rose gradually during mouse embryonic development. In new-born and adult brains, we found abundant DGKCξ protein. We further examined the expression pattern of DGKCξ in mouse embryos by whole-mount RNA in .situ hybridization. In E11.5 embryos, we observed low level expression in spinal ganglia and limb buds. Expression of DGKCξ in spinal ganglia and limb buds became much stronger in E12.5 embryos. DGKCξ staining highlighted the segmentation of spinal ganglia along the embryo. In E13.5 day embryos, DGKCξ was highly expressed in follicles of vibrissa, spinal ganglia, and limb buds. Strong staining also was found in (he umbilical vessels of embryos. We also detected staining in the brains of the embryos. Details of the localization of the signals in the brain are currently under investigation. Taken together, we conclude that DGKCξ gene expression is regulated temporally and spatially during mouse embryonic development.