| |
Figure 10. Inhibition of Xqua function results in down-regulation of early notochord marker mRNAs. mRNA (2.5 ng) encoding the dominant-negative pXqua protein δD or δD plus β-galactosidase was microinjected into the equatorial region of each of the two dorsal blastomeres at the four-cell stage. The resulting embryos, together with uninjected control embryos, were fixed at gastrula stages and analyzed by whole-mount in situ hybridization for expression of early dorsal mesoderm and notochord mRNA markers:Xnot-2 (A–C), Xbra (D–I), andgsc (J–L). Arrows indicate the location of the dorsal lip in early stage embryos. In C, F, I, and L,embryos were stained with X-gal (blue) prior to in situ hybridization (purple/brown), to indicate the cells that received the δD mutant. Overexpression of δD in the dorsal mesoderm results in disruption of gastrulation and a loss of detectable Xnot-2, Xbra, and gsc transcripts in recipient cells. |
