Ccr7 is required for proper AP and DV embryo patterning.

<p>(A) The spectrum of dorsalized phenotypes in embryos injected with MO1-<i>ccr7</i> at 27 hpf, ranging from highly dorsalized (C4–5; b) with truncated tails and trunks to C3 with tail deficiencies (b′) (total <i>n</i> = 190, seven independent experiments for 12 ng MO1-<i>ccr7</i> and <i>n</i> = 35, one experiment for 20 ng MO1-<i>ccr7</i>). The frequency of each phenotypic category is indicated in the right panel (c). The scale bars represent 200 µm in all figures. (B) Ccr7 overexpression (150–200 pg RNA) caused a spectrum of ventralized phenotypes, ranging from V3 to V1 (arrows show anterior and notochord deficiencies) to WT-like (a). The frequency of each phenotypic category is indicated in the right panel (b; <i>n</i> = 96, two experiments). (C) Expression of dorsal/ventral markers in Ccr7 morphants compared to control embryos revealed by WISH. (a–e′) Expression of dorsal genes was upregulated or expanded: at high-oblong stage (3.3–3.7 hpf), <i>boz</i>, <i>n</i> = 8/8; at sphere stage (4 hpf), <i>boz</i>, <i>n</i> = 16/28; <i>mkp3</i>, <i>n</i> = 9/12; <i>chd</i>, <i>n</i> = 11/15; at shield stage (6 hpf), <i>gsc</i>, <i>n</i> = 18/37. (f–j′) Expression of ventral genes was reduced: at dome (4.3 hpf) stage, <i>bmp2b</i>, <i>n</i> = 19/24; at 30% epiboly stage (4.7 hpf), <i>ved</i>, <i>n</i> = 12/14; at shield stage, <i>bmp4</i>, <i>n</i> = 9/10; <i>szl</i>, <i>n</i> = 11/12; <i>vox</i>, <i>n</i> = 16/22. Animal views, dorsal to the right. (D) Expression of dorsal/ventral markers in Ccr7-overexpressing embryos revealed by WISH. Expression of ventral markers was expanded (a–c′), while dorsal markers were decreased (d–e′): at sphere stage, <i>boz</i>, <i>n</i> = 8/8; <i>chd</i>, <i>n</i> = 10/13; at 40% epiboly stage (5 hpf), <i>bmp2b</i>, <i>n</i> = 12/12; <i>bmp4</i>, <i>n</i> = 14/14; <i>szl</i>, <i>n</i> = 13/13. Animal views, dorsal to the right.