Fig. 1.

Defects in epithelial repair in Toll^−/− and Dif dl mutant embryos following laser ablation. (A) Controls (w¹¹¹⁸) closed inflicted epidermal lesions in 92.5% of the tested embryos (n = 157). Arrow points to a closed wound. (B) Wounded spz embryos were able to close wounds in the ventral epidermis in 84.2% of the tested mutants (n = 143). Arrow shows a closed wound. (C) Toll^−/− embryos failed to close experimentally introduced wounds in 70.3% of the tested mutants (n = 64). Arrow points to an open epidermal gap. (D) Dif dl mutants did not close wounds after laser ablation of a patch of the ventral epidermis in 65.3% of the tested embryos (n = 87). Arrow marks the open wound. Although ablation is always done ventrally, after 16 h of recovery, the open wound could be found on the lateral side in Toll^−/− and Dif dl mutants. The number of embryos for each genotype constitutes the combined counts from six to nine independent wounding sessions. The Toll transallelic combination represents a strong loss-of-function phenotype; Dif dl double mutants and spz mutants represent a null phenotype.