Fig. 6

Identification of putative cnidocyte-specific transcription factors. a–d Cnidocyte abundance was characterized in gastrula-stage embryos labeled with α-NCOL4 antibody in a unmanipulated embryos or following microinjection of b standard control morpholino (Ctrl MO), c SoxB2 ATG MO, or d SoxB2 5UTR MO. Nuclei were labeled with DAPI (insets), and cnidocyte abundance was measured relative to the total number of labeled nuclei in each embryo. e Cnidocytes comprise approximately 9% of the cells of the ectoderm in uninjected and control MO-injected embryos and only 4% of the cells in SoxB2 MO embryos (uninjected: 8.98 ± 0.45, control MO: 9.11 ± 0.33, SoxB2 ATG MO: 3.82 ± 1.84, SoxB2 5UTR MO: 5.27 ± 0.34; mean ± standard error). Asterisk indicates significant difference from control MO-injected embryos. f Relative mRNA expression of target genes assayed by qRT-PCR following microinjection of SoxB2 MO. The expression of housekeeping gene EF1B in SoxB2 morphants relative to embryos injected with control MO was set to 1.0, and all other expression values are reported relative to this. The y-axis is presented in log scale. Mean ± standard error. Asterisk indicates significant difference from Ef1B. g In situ hybridization of cnidocyte-specific genes in control MO-injected and SoxB2 MO-injected embryos validating the results of qRT-PCR analysis. Images in g are DIC micrographs