Effects of <i>Wnt11</i> silencing on dermomyotome.

<p>A, C, E, G and I. Chicken embryos electroporated with <i>Wnt11</i> RNAi at stage HH14-17 and after a reincubation period of 24 hours. B. The embryo in A (HH20) hybridized for <i>En-1,</i> shows that the central dermomyotomal compartment marked with <i>En-1</i> was unaffected in the electroporated area (the space between white arrows in B). D. The photo represents the embryo in C after ISH for <i>Sim-1</i> probe. The lateral dermomyotomal compartment marked with <i>Sim-1</i> (white arrows in D indicate the electroporated area) did not show any change in its expression after <i>Wnt11</i> silencing. F. ISH for <i>Paraxis</i> of the embryo presented in photo E. <i>Paraxis</i> transcripts seems not to be altered following <i>Wnt11</i> silencing in the DML (area between white arrows in F). H. The dermomyotomal marker <i>Pax3</i>, in contrast, is significantly upregulated at the site of <i>Wnt11</i> RNAi transfection (area between white arrows in H). K. The cross-section through the embryo in H in the manipulated area shows a strong upregulation of <i>Pax3</i> in the DML, while the DM remains normal when compared to the control side. I. Electroporated embryo at stage HH14-17 with <i>Wnt11</i> RNAi and after 24 hours reincubation (HH19). J. Hybridized embryo from photo I for <i>Snail1</i> probe. At stage HH20 the EMT has already started, and the <i>Snail1</i> expression can be seen in the myotome, dermomyotome, sclerotome and in the space above the neural tube (dermal progenitor cells). Whole-mount ISH of the embryo electroporated with <i>Wnt11</i> RNAi shows a decreased <i>Snail1</i> expression (the region in the bracket), while the white arrows point towards the normal expression of <i>Snail1</i> above the neural tube (dermogenic progenitors) at untreated levels. L. Section through the embryo in J in the affected region shows a decreased <i>Snail1</i> expression in the DML (black arrowhead) and above the neural tube (black arrow). Scale bar: 100 μm.