MOESM3 of The role of HoxA11 and HoxA13 in the evolution of novel fin morphologies in a representative batoid (Leucoraja erinacea)

Additional file 3. Reverse collinear (RC) expression in the claspers of the little skate. RC expression occurs when the more posterior gene has a broader expression range than the gene anterior to it. In this case, HoxA13 is expressed throughout the entire clasper (B), whereas HoxA11 is restricted to the distal region (A). This expression pattern is likely setting up left–right asymmetry in the claspers and is only observed at stage 32 of development. Arrows denote HoxA11 expression in the distal claspers.