Fig. 1: Skeletal muscle development.

a Scheme of the mesoderm patterning along the mediolateral axis by gradients of specific signaling molecules, as Noggin and BMP. D dorsal, L lateral, M medial, V ventral, R rostral, C caudal. b Color-coded scheme of the differentiating somites and the surrounding structures during gastrulation and neurulation. Signaling molecules are indicated in green if acting as pro-differentiative actors, in red if they inhibit the differentiation process; dashed lines show paths of cell migration. c Representation of the differentiation process of skeletal muscle cells of the axial and limb muscles, starting from the paraxial mesoderm (PM) progenitors. Marker genes are shown in the bottom boxes, while the main signaling molecules are indicated in green if acting as pro-differentiative actors, in red if they inhibit the differentiation process. PSM presomitic mesoderm, SM skeletal muscle. Schemes adapted and modified from^35,206.