Fig. 3
Expression pattern of fox gene Dg-foxg (a–c), six class gene Dg-six3/6 (d–f), neuropeptidergic differentiation factor Dg-dim (g–i) and NK homeobox genes Dg-nk2.1 (j–l) and Dg-nk2.2 (m–o) in adult female Dinophilus gyrociliatus. The expression pattern of the respective gene is shown in ventral (a, d, g, j, m) and lateral (ventral side to the left, b, e, h, k, n) views as well as in schematic drawings in ventral view (c, f, i, l, o). Dg-foxg resembles the pattern of Dg-hbn, but shows more prominent labeling in the anteromedian region and the posterolateral patches, which are shifted anterior to the centers of Dg-hbn (a–c). Dg-six3/6 labels cells in the entire brain though the ventral side shows gaps between the anterior and posterior continuous patches. Additionally, the anterolateral ectodermal regions of the mouth and pharynx are labeled (d–f). Dg-dim shows a complex pattern with a dorsomedian expression, which bifurcates ventrally in the anterior and posterior region, forming a clasp embracing the neuropil (g–i). Dg-nk2.1 is expressed strongest in the anterior region of the brain and only weakly in the posterior part. However, Dg-nk2.1 also labels the foregut in adult females (j–l) as well as the hindgut, which is complemented by Dg-nk2.2, which does not label the brain (m–o), but the midgut. br brain, cbg ciliary band gland, fg frontal gland, mo mouth opening, np neuropil, pcb prostomial ciliary band, phb pharyngeal bulb, vrcc ventral root of the circumesophageal connective