Serine proteases are sufficient and required for epidermal wound response gene transcription.

<p>Confocal images of wild-type embryos after <i>in situ</i> hybridization with fluorescently labeled RNA probes made to detect transcripts from <i>ple</i> (magenta) and <i>Ddc</i> (red). (A, B) 30 minutes after HCl (trypsin buffer) puncture wounding, <i>Ddc</i> and <i>ple</i> transcripts accumulate in the epidermis around the wound site. (C, D) 30 minutes after puncture-trypsin wounding, <i>ple</i> and <i>Ddc</i> transcript accumulation can be observed throughout a large region of the epidermis. (E) One hour after water puncture wounding, wild-type embryos activate <i>Ddc</i> transcripts in the epidermis surrounding the wound site. (F) One hour after Pefabloc puncture wounding, no <i>Ddc</i> transcripts are activated in the epidermis surrounding the wound site in wild-type embryos, but normal developmental expression of <i>ple</i> in the cells that secrete the head skeleton is observed (magenta). Gut autofluorescence is seen in red. (G) In wild-type, double water puncture wounded embryos, 60 minutes after the first water puncture wound, a moderately wide zone of <i>Ddc</i> transcripts in the epidermis around wound sites is observed, while 30 minutes after the second wound, a narrow zone of <i>Ddc</i> transcript accumulation is observed around the wound site. (H) In wild-type double puncture wounded embryos with Pefabloc injected at the second site, 60 minutes after the first puncture wound, a narrow zone of accumulation of <i>Ddc</i> transcripts in the localized epidermis is observed around the first wound site, while 30 minutes after the second puncture wound with Pefabloc, no <i>Ddc</i> transcript accumulation is observed at the wound site. Arrows mark the wound sites. “1″ and “2″ indicate first and second wounds, respectively. Dashed lines in the data panels mark the outlines of embryos.