Figure 1
Expression of AfaMHC during Acanthochitona fascicularis development. (B, D, F, H, J, L) are schematic representations of gene expression signatures of the respective developmental stages. Colour code indicates respective muscle systems. (A–D) AfaMHC expression in the early trochophore larva (A) AfaMHC expression in the developing rectus, enrolling, and ventrolateral muscles. (B) Ventral view of the developing muscles. (C) Lateral right view of the AfaMHC expression in developing muscles. (D) Lateral right view. (E–H) AfaMHC expression in the late trochophore larva. (E) AfaMHC expression is found in all muscles. Dorsally located muscles such as the rectus muscle and the transversal muscles are partially masked by the intense staining of the more ventrally positioned muscles. (F) Ventral view. Rectus and transversal muscles are not shown. (G) Lateral view showing weak expression in the transversal muscles. (H) Lateral right view. (I–L) AfaMHC expression in the early juvenile. (I) AfaMHC expression is retained in the enrolling muscle, the ventrolateral muscle, the dorsoventral muscles, and the transversal muscles. (J) Ventral view. (K) Lateral right view of AfaMHC expression. (L) Lateral right view. Asterisks mark the mouth. Roman numbers correspond to the future juvenile shells. a anterior, d dorsal, l left, p posterior, r right, v ventral. Scale bars equal 20 µm. Expression pattern schemes were designed with Inkscape (version 0.92.4; https://inkscape.org) and Gimp 2 (Version 2.8.22; https://www.gimp.org).
