A ubiquitin promoter drives expression of a shg mutant tagged with a C-terminal EGFP. The shg mutants contains three amino acid substitutions (G1010L, S1011L and P1012L) at the proteolytic cleavage site "GSP".
shgmNcGSP.Ubi.T:Avic\GFP-EGFP can rescue the lethality of of shgR69. The rescued embryos show normal ventral furrow and the ventral midline cells meet entirely.