Expr7480

2 of 7 lines examined showed the same but weak extensive nervous system expression from late embryo to adult. The low level of expression may be the reason for the lack of expression in most lines examined.

Expr2822

When transgenic worms harboring the GFP-tagged rcq-5 gene were observed under a fluorescence microscope, GFP was localized in nuclei of late embryos at the 3-fold stage and in the nuclei of many somatic cells in larvae and adult worms. Although GFP appeared ubiquitous in the worms, its intensity was relatively strong in the intestine, which coincided with the intestinal GFP expression in late embryos. The main reason why GFP expression was not seen in early embryos and gonads is cosuppression mediated by multi-copy transgenes in the C. elegans germ-line. A 0.5 kb long 5 -upstream DNA was adequate to induce reporter gene expression with the same pattern.

Expr1584

The large majority of ceh-10 mRNA is found in the embryo and likewise the majority of ceh-10 directed reporter gene expression is also found within the embryo. The earliest point at which ceh-10/lacZ expression can be detected is in a single nucleus at the extreme anterior pole of the embryo, at mid-proliferation stage when the embryo has approximately 350 cells. In late proliferation stage embryos, two nuclei and then four nuclei, all at the embryo anterior, express the transgene. As the embryo begins morphogenesis, six nuclei, all at the very anterior pole, stain for beta-galactosidase activity. By the 1.5-fold stage, the embryo has eight staining nuclei, six at the anterior and two additional cells just ventral to the posterior bulb of the pharynx. By the time the embryo has completed morphogenesis, up to twelve staining nuclei can be detected. ceh-10/lacZ expression in L1 larvae is somewhat variable, in that staining in a particular cell is not always seen in every larva; the likely reason is that the level of ceh-10 mRNA declines after hatching and beta-galactosidase staining in L1 larvae presumably results from enzyme perdurance. Most ceh-10/lacZ staining occurs in the region around the nerve ring, which is dense with the nuclei and processes of neurons. The expressing anterior nuclei were identified as: AIYL/R (interneurons), CEPDL/R (mechanosensory neurons), RID (motor neuron), ALA (lateral neuron), RMED (nerve ring motor neuron), AINL/R (interneurons) and AVJL/R (ventral neurons). ceh-10 is also expressed in the CAN cells (the excretory Canal Associated Neuron).